Grant MonoWave SystemIndirect Heat Pump Cylinder Range

Installation & User Instructions

Part No. DOC 74. Rev 04. January 2011

Storage Cylinder

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Contents1 Introduction &

General Requirements 31.1 Installation Requirements 3

1.2 Water Supply Requirements 3

1.3 Location 3

1.4 Storage and Handling 3

1.5 About Your New Cylinder 3

1.6 Open Vented Hot Water Systems 3

1.7 Taps and Fittings 3

1.8 Pipework Connections 3

1.9 Scaling 3

1.10 Insulation 3

1.11 Health and Safety 3

2 Technical Specifications 42.1 Technical Data 4

2.2 Dimensions 5

2.3 Connections and Controls 6

3 Primary Circuit Installation 73.1 Grant MonoWave HP Cylinders 7

3.2 Primary Connections 7

3.3 The 2-Port Valve 7

3.4 Hard Water Areas 7

4 Secondary Circuit Installation 84.1 Cold Water Inlet Manifold 8

4.2 Installation 8

4.3 Expansion Vessel 8

4.4 Temperature and Pressure Relief Valve 8

4.5 Hot Water Supply 8

4.6 Prevention of Scalding 8

4.7 Secondary Return 9

4.8 Tundish 9

4.9 Discharge Pipe 9

4.10 Discharge Pipe Arrangement 10

4.11 Discharge Pipe Sizing 10

4.12 Worked Example 10

5 Electrical Installation 115.1 Immersion Heater 11

5.2 Immersion Heater Wiring Instructions 11

5.3 Dual Thermostat 11

5.4 2-Port Valve 11

5.5 'S' Plan System 12

6 Commissioning, Draining Down & Safety 136.1 Filling the Cylinder 13

6.2 Draining Down 13

6.3 Safety Cut-Out 13

6.4 Cold Water Discharge from Tundish 13

6.5 Hot Water Discharge from Tundish 13

6.6 Expansion Vessel 13

6.7 Customer Handover 13

7 Maintenance 147.1 Servicing and Maintenance 14

7.2 Manifold Assembly 14

7.3 Pressure Reducing Valve 14

7.4 Expansion Relief Valve Cartridge 14

7.5 Expansion Vessel 14

8 Fault Finding 158.1 Intermittent Water Discharge 15

8.2 Constant Water Discharge 16

8.3 No Flow from Hot water Taps 16

8.4 Cold Water Flow from Hot Water Taps 17

8.5 Excessive Hot Water from Taps 18

9 Spare Parts 199.1 Spare Parts 19

10 User Instructions 2010.1 User Instructions 20

11 Warranty 2111.1 The Grant Cylinder Warranty 21

11.2 Extended Warranty 22

1 Introduction & General Requirements1.1 Installation RequirementsThank you for purchasing a Grantunvented hot water storage cylinderfrom our Wave range. This installationmanual must be read carefully beforeyou begin installing the cylinder.

This cylinder must be installed by acompetent person in compliance withall current legislation, codes of practiceand local by-laws covering theinstallation of an unvented hot watercylinder. Please also make sure that anyinstallation complies with theinstructions contained in this installationinstruction manual.

1.2 Water Supply RequirementsWe recommend that your GrantUnvented cylinder is installed with anuninterrupted water supply.

Where possible the unit should be fedvia a Ø22mm supply pipe. It requires asupply pressure of 1.5bar with a flowrate of at least 20 litres per minute as aminimum for it to function. Even withthese rates, flow from the outlets will bedisappointing if several outlets are usedsimultaneously. Generally speaking, thehigher the supply pressure, the betterthe system will function. The cylindercontrol equipment is factory set to limitthe incoming system operating pressureto 3bar. The maximum supply pressureinto the pressure reducing valve (PRV)is 12bar.

1.3 LocationThe unit is designed to be floorstanding, vertically mounted, indoors, in a frost-free environment. Whenchoosing a suitable location for thecylinder, consideration should be givento the routing of the discharge pipe to aconvenient point and also the availabilityof an adequate power supply forconnecting the immersion heater(s).

The cylinder may stand on any flat andlevel surface without any specialfoundation preparations, provided that itis sufficiently robust to support the fullweight of the cylinder. (Refer toTechnical specifications for weights).

The position of the cylinder should besuch that easy access is provided forservicing the controls and replacing theimmersion heater should the need arise.

Generally, pipe runs should be made asshort as possible and lagged to preventheat loss.

1.4 Storage and Handling If the cylinder is not being installedimmediately, it should remain in itscarton to prevent damage. Werecommend that the cylinder betransported to its installation position on a sack truck or similar whilst stillwithin the carton.

1.5 About Your Cylinder MonoWave HP indirect cylinders haveone coil specifically designed forconnection to an air source heat pump,such as the Grant Aerona range. If asource such as Solar Thermal oranother make of heat pump is to beconnected, please refer to themanufacturers installation instructionsfor more information.

The coil must be connected using a 2-port motorised valve (for solarinstallations a high temperature 2-portor solenoid valve must be used) to shutoff the flow from the primary source andelectrically interlocked with the heatsource via the cylinder control and limitthermostat.

Failure to do so will invalidate allwarranties and will be in breach of The Building Regulations ApprovedDocument G3 (2010).

More information on electrical wiring isgiven on page 11.

MonoWave HP indirect cylinders arealso supplied fitted with a 3kW electricimmersion heater (two are supplied withthe 300 and 400 models).

Refer to page 11 for further details onimmersion heaters.

1.6 Open Vented Hot WaterSystemsIf required, your Grant MonoWave HPCylinder can be used as part of anOpen Vented hot water system, i.e. fedfrom a cold water storage cistern andfitted with an Open Vent pipe, providedthe maximum head does not exceed30m.

When used in this way, it will not benecessary to install the expansionvessel and cold inlet manifold suppliedwith the cylinder.

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Note: The Temperature and Pressurerelief (T&P) valve should be leftconnected to the cylinder (as supplied).As it may still operate due totemperature it should be connected inthe correct manner – refer to guidancegiven in Section 4 of these Instructions.

1.7 Taps and FittingsAll taps and fittings incorporated in theunvented system should have a ratedoperating pressure of 7 bar or above.

1.8 Pipework ConnectionsAll Pipework connections to the cylindermust be made in accordance withFigures 2-3 or 2-4 as appropriate.

1.9 ScalingIn hard water areas scaling will forminside the cylinder and this will reduceboth the performance and working lifeof the cylinder. Where the totalhardness exceeds 125ppm a highcapacity water softener, or suitablewater conditioner, should be installed inthe incoming cold water supply to thecylinder.

It is recommended that the watertemperature control thermostats (on theimmersion heaters and dualthermostats) fitted to the cylinder be setno higher than 60°C to minimise scalebuild up.

1.10 InsulationAll Grant Cylinders are insulated with40mm thick CFC/HFC free, fireretardant, polyurethane foam injectedbetween the stainless steel cylinder andthe outer casing. This polyurethanefoam has a Global Warming Potential(GWP) of less than 3 and an OzoneDepletion Potential (ODP) of 0.

1.11 Health and SafetyThe information supplied in the table inSection 2 Technical Specification willhelp you assess the safest way tomanoeuvre your cylinder into position.Please use the table to find the emptyweight of your cylinder and thenconsider how you can safely move itinto its final position.

Please leave this manual with thehouseholder after installation.

2 Technical Specifications

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2.1 Technical Data

MonoWave HP Indirect Cylinders

Model Number 125 150 170 200 250 300 400

Storage capacity (litres) 125 150 170 200 250 300 400

Overall diameter (mm) 580 580 580 580 580 580 580

Overall height - with expansion vessel on cold supply (mm) 800 890 1075 1230 1480 1745 2110

Weight empty (kg) 30 32 45 49 59 68 76

Weight full (kg) 155 182 215 249 309 368 476

Secondary return connection (mm) 22 22 22 22 22 22 22

Cold feed/hot draw-off connections (mm) 22 22 22 22 22 22 22

Primary coil connections (mm) 22 22 22 22 22 22 22

Primary coil length (m) 11.68 13.90 13.90 23.36 23.36 27.80 27.80

Primary coil surface area (m2) 1.5 2.0 2.0 3.5 3.5 4.0 4.0

Primary coil pipe diameter (mm) 22 22 22 22 22 22 22

Maximum water supply pressure (bar) 12 12 12 12 12 12 12

System operating pressure - pre-set (bar) 3 3 3 3 3 3 3

Expansion vessel charge pressure (bar) 3 3 3 3 3 3 3

Expansion relief valve pressure (bar) 6 6 6 6 6 6 6

Temp & pressure relief valve lift pressure (bar) 7 7 7 7 7 7 7

Temp & pressure relief valve lift temperature (°C) 90 90 90 90 90 90 90

Maximum primary circuit working pressure (bar) 3 3 3 3 3 3 3

Performance:

Primary coil rating (kW) 24.0 27.8 27.8 47.0 47.0 56.6 56.6

24 hr standing loss (kW)* 1.70 1.92 2.04 2.45 2.69 2.71 2.94

Check list:

Cylinder assembly 125 litre 1 - - - - - -

Cylinder assembly 150 litre - 1 - - - - -

Cylinder assembly 170 litre - - 1 - - - -

Cylinder assembly 200 litre - - - 1 - - -

Cylinder assembly 250 litre - - - - 1 - -

Cylinder assembly 300 litre - - - - - 1 -

Cylinder assembly 400 litre - - - - - - 1

Expansion vessel 12 litre 1 1 - - - - -

Expansion vessel 19 litre - - 1 1 - - -

Expansion vessel 24 litre - - - - 1 1 -

Expansion vessel 35 litre - - - - - - 1

Expansion vessel hose (3/4" BSPF x 3/4" BSPM) c/w washer 1 1 1 1 1 1 1

Expansion vessel wall bracket and band 1 1 1 1 1 1 1

Adaptor (1" BSPF x 3/4" BSPM) - - - - - - 11/2" Temp & pressure relief valve (7 bar 90ºC) factory-fitted 1 1 1 1 1 1 1

Tundish 15/22mm 1 1 1 1 1 1 1

Drain cock (1/2" end feed) 1 1 1 1 1 1 1

Inlet manifold (3 bar pressure reducing valve & 6 bar exp. relief valve) 1 1 1 1 1 1 1

2-port motorised valve 22mm 1 1 1 1 1 1 1

Dual thermostat (Control 25-65ºC High limit 90ºC) 1 1 1 1 1 1 1

Immersion heater 3 kW (13/4" boss) factory-fitted 1 1 1 1 1 2 2

* Test carried out at 60˚C.

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Figure 2-2: MonoWave HP indirect cylinder dimensions

Dims Model(mm) 125 150 170 200 250 300 400

A 210 210 210 210 210 210 210

B N/A N/A N/A N/A N/A 872 1015

C 460 500 635 765 1020 1290 1550

D 580 670 855 915 1260 1525 1890

E 740 830 1025 1170 1430 1695 2050

F 800 890 1075 1230 1480 1745 2110

Dia 580 580 580 580 580 580 580

MonoWave HP Indirect Cylinder Dimensions

2.2 Dimensions

Dia

ABCDEF

40˚ 30˚22mm Hot water

draw off

1/2" T & P Reliefvalve (factory fitted)

22mm Heat pumpflow

22mm Heat pumpreturn

22mm Secondaryreturn

Immersion heater(factory fitted) on

300 & 400models only

22mm Cold waterinlet

Immersion heater(factory fitted)

Heat pump statpocket

0˚30˚

2 Technical Specifications

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Figure 2-3: MonoWave HP indirect cylinders- 125, 150, 170, 200 & 250

Figure 2-4: MonoWave HP indirect cylinders - 300 & 400

2.3 Connections and Controls

Item Description Connection Size

1 Hot water draw off 22mm

2 T & P valve connection 1/2" BSPF

3 Secondary return 22mm compression

4 Heat pump return tapping 22mm compression

5 Dual stat pocket -

6 Cold water inlet 22mm compression

7 Heat pump flow tapping 22mm compression

8 Immersion heater c/w control & limit thermostat (factory fitted) 13/4" BSPF

8A Immersion heater c/w control & limit thermostat (factory fitted) 13/4" BSPF300 & 400 only

9 Pressure reducing valve - 3 bar -

Item Description Connection Size

10 Balanced cold supply connection 22mm compression

11 Expansion relief valve - 6 bar 15mm compression

12 Temperature & Pressure relief valve - 90°C/7 bar 15mm compression

13 Tundish 15/22mm compression

14 Discharge pipe (not supplied with cylinder) -

15 Mains water supply pipe (not supplied with cylinder) -

16 Drain cock (supplied with cylinder) -

Note:Pipework between items 11 and 12 not supplied with cylinder.

1

9

10

11

12

17 17

1415

16

2 4 7

3

5 86

1

9

10

11

12

1415

16

2 4 7

3

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3 Primary Circuit InstallationIndirect models only

3.3 The 2-Port ValveTo prevent gravity circulation when theboiler or heat pump switches off, the 2-port motorised valve supplied withthe unvented hot water kit, must befitted in the primary flow pipe to thecylinder and wired in accordance withFigure 5-3 for a Grant Aerona heatpump to comply with current legislation.

For other makes of heat pump pleasecheck with the heat pump manufacturerfor connection details.

3.4 Hard Water AreasIf the cylinder is to be used in a hardwater area, we recommend that theprimary flow temperature be limited to75ºC. This will help reduce themigration of suspended solids in thewater and help prevent the build up oflime scale.

3.1 Grant MonoWave HPCylindersGrant MonoWave HP indirect cylindersare specifically designed for connectionto most fully pumped Air Source HeatPump systems (such as the GrantAerona Heat Pump range) - either openvented or sealed systems having amaximum working pressure of 3 barand a maximum working temperature of 90ºC.

If you are in any doubt over thesuitability of an Air Source HeatPump (other than a Grant Aeronaheat pump) for use with the cylinder,consult the heat pump manufacturer.

IMPORTANTSolid fuel or wood burning boilers andgravity circulation systems must not beused on the primary circuit of anunvented hot water system.

3.2 Primary Connections1. The primary flow and return

connections from the heat pumpshould be made to the flow andreturn connections of the cylinder.Refer to either Figures 2-3 or 2-4 asappropriate.

The motorised valve (supplied) mustbe fitted into the primary flow. Theprimary flow and return fittings are22mm compression. The valve has22mm compression connections.

2. Locate the dual thermostat in thestainless steel pocket (refer to eitherFigures 2-3 or 2-4, as appropriate,for location) and secure using theretaining screws on the thermostathousing.

3. Any automatic or manual air ventfitted to vent air from the upper coilshould be installed on the primaryflow pipe to the coil.

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4 Secondary Circuit Installation4.1 Cold Water Inlet ManifoldThis manifold contains a pressurereducing valve (with integral strainer),double check valve, expansion valvewith a stainless steel seat. The pressurereducing valve is factory set. The setpressure is shown on top of the valve.Maximum inlet pressure to valve is 12 bar.

4.2 Installation1. Cold water supply to be 22mm

nominal size.

2. Flush supply pipework beforeconnection to remove all flux anddebris prior to fitting the inletcontrols. Failure to do this mayresult in irreparable damage tothe controls and will invalidatethe warranty. Once the pipeworkis flushed connect the coldsupply to the Inlet manifold.

3. The manifold can be installed in anyposition as long as it is installed inthe correct flow direction. Refer tothe arrows on the side of the body.Make sure that the head of theexpansion relief valve is offset fromthe cylinder for ease of access.

4. The expansion relief valve should beeither horizontal or upright - if fittedinverted, debris may be depositedon the seat and cause fouling of theseat when the valve operates.Check direction of flow arrows.

5. The black plastic plug in the body isa pressure gauge connection toenable pressure monitoring to becarried out, should the systemdevelop a fault. It is recommendedthat this be accessible.

4.3 Expansion VesselA suitable expansion vessel with a pre-charge pressure of 3bar is supplied forfitting to all cylinders.

The supplied expansion vessel must beconnected into the cold water supply,between the expansion relief valve (inthe inlet manifold) and the cylinderusing the flexible hope provided. Theexpansion vessel must be positionedwith the entry point at the bottom. Novalve should be fitted between theexpansion vessel and cylinder.

The air charge pressure in theexpansion vessel must be regularlychecked (e.g. at every service) andtopped up as necessary. The correct aircharge pressure is 3.0bar.

Refer to Sections 7.1 and 7.5 for furtherdetails.

4.4 Temperature and PressureRelief ValveThe temperature and pressure reliefvalve (T&P Valve) is supplied factoryfitted to the cylinder. The T&P valvemust not be removed from the cylinderor tampered with in any way. The valveis pre-set to lift at 7bar or 90°C andany attempt to adjust it will invalidatethe warranty.

4.5 Hot Water SupplyConnect the hot water supply pipe tothe top outlet (1) of the cylinder.

4.6 Prevention of ScaldingBuilding Regulations ApprovedDocument G (Part G3) requires that thehot water temperature supplied to abath should be limited to a maximum of48°C by using an in-line blending valve(not supplied with the cylinder) with amaximum temperature stop. The lengthof the supply pipe between theblending valve and the bath hot wateroutlet should be kept to a minimum toprevent the colonisation of waterbornepathogens (e.g. legionella). Refer toApproved Document G for furtherdetails.

6. Expansion relief drain pipeworkmust be connected to a safe visibledischarge point via a tundish andthe pipework must have acontinuous fall. Connect theExpansion Relief valve outlet intothe discharge pipe from theTemperature and Pressure Reliefvalve using a 15mm copper pipeand tee piece (not supplied). Fit theTundish below this tee piece usinga short length of copper pipe. Referto Sections 4.7, 4.8 and 4.9 forfurther information on Tundish andDischarge pipe.

7. The pressure reducing valve hastwo outlets, the second one is for abalanced cold water supply, to ashower or a bidet (over rim typeonly, ascending spray typerequires type AA, AB or AD airgap). Major shower manufacturersadvise fitting a mini expansionvessel in the balanced coldsupply to accommodate thermalexpansion and prevent tighteningof shower controls. If thedwelling has a shower mixingvalve (manual or thermostatic) ora Bidet (over rim type) use thecold water supply from theBalanced Cold water connectionon the Inlet Manifold for theseoutlets. Do not use the balancedcold connection to supply bathtaps as this can reduce the flowof water available to the cylinder.If the balanced cold water outlet isnot required, blank off the port.

The Benchmark book enclosed withthe cylinder should be completedafter commissioning of the system.

The cylinder must be registeredwith Grant UK within 30 days ofinstallation. Refer to Section 11 forfurther details on the CylinderWarranty.

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4.8 Tundish The tundish must not be positionedabove or in close proximity of anyelectrical current carrying devices orwiring.

4.9 Discharge Pipe1. The discharge pipe from the

Tundish should terminate in a safeplace where there is no risk topersons in the vicinity of thedischarge, be of metal and:

a) Be at least one pipe size larger thanthe normal outlet size of the safetydevice unless its total equipmenthydraulic resistance exceeds that ofa straight pipe 9m long, i.e.discharge pipes between 9m and18m equivalent resistance lengthshould be at least larger than thenormal outlet size of the safetydevice, between 18m and 27m atleast three sizes larger and so on.Bends must be taken in to accountin calculating the flow resistance.See Sections 4.10, 4.11 and 4.12.

b) Have a vertical section of pipe atleast 300 mm long, below thetundish before any elbows or bendsin the pipe work.

c) Be installed with a continuous fall of1:40 (2.5°).

d) Have discharges visible at both thetundish and the final point ofdischarge but where this is notpossible or practically difficult thereshould be clear visibility at one orother of these locations.

2. Examples of acceptance dischargearrangements are:

a. ideally below a fixed grating andabove the water seal in a trappedgully.

b. downward discharges at a lowlevel; i.e. up to 100mm aboveexternal surfaces such as car parks,hard standings, grassed areas etc.are acceptable providing that wherechildren may play or otherwisecome in to contact with discharges,a wire cage or similar guard ispositioned to prevent contact,whilst maintaining visibility.

c. discharges at high level; e.g. in tometal hopper and metal down pipewith the end of the discharge pipeclearly visible (tundish visible or not)or onto a roof capable ofwithstanding high temperaturedischarges of water and 3m from

any plastics guttering systems thatwould collect such discharges(tundish visible).

3. Where a single pipe serves anumber of discharges, such as inblocks of flats, the number servedshould be limited to not more than6 systems so that any installationcan be traced reasonably easily.The single common discharge pipeshould be at least one pipe sizelarger than the largest individualdischarge pipe to be connected. If unvented hot water storagesystems are installed wheredischarges from safety devices maynot be apparent i.e. in dwellingsoccupied by blind, infirm or disabledpeople, consideration should begiven to the installation of anelectronically operated device towarm when discharge takes place.

Note:The discharge will consist ofscalding water and steam. Asphalt,roofing felt and non-metallicrainwater goods may be damagedby such discharges.

Balanced cold supply for showersor bidet only (see Section 4.2)

Secondaryreturn line

Circulationpump

Non returnvalve

Cold inlet

Balanced coldsupply outlet

Figure 4-1: Secondary Return Circuit

4.7 Secondary ReturnAll MonoWave HP cylinders are fitted with a secondary return connection. If a secondary return circuit isrequired it should be connected to the MonoWave HP cylinder as shown below:

Note:If a secondary circulation circuit is installedthen a larger expansion vessel may berequired to handle the increase in volume.

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4 Secondary Circuit Installation4.10 Discharge Pipe Arrangement

Figure 4-2: Typical discharge pipe arrangement

Safety device ( e.g.temperature relief valve)

Metaldischargepipe fromtemperature

Metal discharge pipe from tundishwith continuous fall. See table andworked example on next page

discharged belowfixed grating

Fixed grating

Trapped gully

Tundish

600mm max

300m

m m

in

4.12 Worked ExampleThe example below is for a 1/2”diametertemperature relief valve with adischarge pipe (D2) having 4 elbowsand a length of 7 m from the tundish tothe point of discharge.

FromMaximum resistance allowed for astraight length of Ø22mm copperdischarge pipe (D2) from a 1/2” diametertemperature relief valve is - 9.0m.

Subtract the resistance for quantity of 4Ø22mm elbows at 0.8m each = 3.2m.Therefore, the maximum permittedlength equates to 5.8m.

5.8m is less than the actual length of7m; therefore calculate the next largestsize.

Maximum resistance allowed for astraight length of Ø28mm-pipe (D2)from a 1/2” diameter temperature reliefvalve equates to - 18m.

Subtract the resistance for a quantity of4 Ø28mm elbows at 1.0 each = 4m.

Therefore the maximum permittedlength equates to 14m.

As the actual length is 7m, a Ø28mmdiameter copper pipe will besatisfactory.

4.11 Discharge Pipe Sizing

Max resistance allowed,Minimum size of expressed as a length Resistance created

Valve outlet size, Minimum size of discharge pipe D2 from of straight pipe, i.e. no by each elbow or diameter (inches) discharge pipe D1 (mm) tundish in (mm) elbows or bends bend in (m)

22 Up to 9 0.81/2 15 28 Up to 18 1.0

35 Up to 27 1.4

28 Up to 9 1.03/4 22 35 Up to 18 1.4

42 Up to 27 1.7

35 Up to 9 1.41 28 42 Up to 18 1.7

54 Up to 27 2.3

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5 Electrical Installation

All electrical wiring must be carriedout by a competent person and inaccordance with the current I.E.E.Wiring Regulations.

The control equipment supplied willensure that the cylinder functions safely.From an economic and conveniencepoint of view, it is intended that thesecontrols operate in conjunction withother control packages for example "S-plan" type system, which incorporate aprogrammable time clock, etc.

5.1 Immersion Heater All cylinders are supplied fitted with oneimmersion heater (two are suppliedfitted with the 300 and 400 models).

Each 3kW 230V 50Hz-immersionheater should be wired in accordancewith the instructions given in Figure 5-1.

The cable must be routed through the strain relief bush. The controlthermostat is pre-set at approximately60°C. The immersion heater conformsto EEC Directive 76/889 for radiointerference and complies with EN60335-2-73.

Installation and wiring instructions forthe immersion heater are supplied witheach unit. Follow the wiring instructionsconnecting the live, neutral and earth asindicated.

The unit must be permanentlyconnected to the electrical supplythrough a double-pole isolator. A safetycut-out is also incorporated within thethermostat and is factory set to operateat 80°C ± 5°C.

IMPORTANTBefore resetting the safety cut-out oraltering the thermostat setting, isolateelectrical supply to the unit prior toremoval of the cover. Investigate andidentify the cause of the cut-outoperation and rectify the fault beforemanually resetting the cut-out bypressing in the reset button. Ensure thecover to the immersion element isreplaced correctly and the retaining nutis fitted. Finally switch the mainselectricity supply back on.

Figure 5-1: Immersion heater wiringconnections

= Earth (Green/Yellow)= Live (Brown)= Neutral (Blue)

Temperaturecontrol dial

Reset

This appliance must be earthed.

! WARNING

The manual re-set high limitthermostat must not under anycircumstances be bypassed. This is pre-set to 80°C and to preventnuisance tripping the controlthermostat should always be left inposition 4.

! WARNING

d) The BEAB approval certification onthis immersion heater only applies ifa Cotherm TSE rod type thermostatis used. The temperature setting ofthe control thermostat shouldalways be left in position 4.

5.3 Dual Thermostat (IndirectTemperature Control) A Dual Thermostat (a combined controland high limit thermostat) is suppliedseparately with the unvented hot watersafety kit. This is fitted into the sensorpocket in the cylinder (see Figures 2-3or 2-4 for position) to control theoperation of the boiler or heat pumpprimary coil.

The control thermostat has anadjustment range between 25°C and65°C, however it is recommended thatit is set to 60°C. The overheatthermostat incorporated within the dualthermostat will operate at 90°C.

5.4 2-Port Valve (Indirect only)To comply with regulations governingthe installation of indirect unventedcylinders, a 2-port motorised valvemust be fitted in the primary flow toprevent gravity circulation when theboiler switches off. Your GrantMonoWave HP unit has been suppliedwith a 2-port motorised valve, which willact as a positive energy cut-out shouldthe safety cutout operate. Should thishappen the motorised valve will operateand close down the primary flow to thecylinder. The valve should be wired inaccordance with Figure 5-3 for a GrantAerona heat pump, to comply withcurrent legislation.

For an air source heat pump (other thana Grant Aerona heat pump) consult theheat pump manufacturer for connectiondetails.

This motorised valve will also controlthe temperature of the domestic storedwater via the cylinder thermostat, whichis located in the upper dual thermostat.The unit should be installed on a "S-plan" system as shown in Figure 5-2.

5.2 Immersion Heater WiringInstructions a) Ensure the main’s voltage

corresponds to the voltage rating of the immersion heater as shownon the rating label on the terminalcover.

b) The immersion heater is factoryfitted to the cyinder. If theimmersion heater needs to bereplaced it must be fitted to thecylinder using the gasket providedon the unit. Use a shaped spanner,Stillsons or pipe grips should not beused. The use of sealing compoundis not recommended.

c) Wire the immersion heater inaccordance with the wiring diagram(Figure 5-1). It should be wiredthrough a double pole isolator switch or controller, with a minimumbreak capacity of 13 amp havingcontact separation of at least 3mm, using 1.5mm sq. flexible cable,85°C rubber insulated HOFRsheathed, to comply with BS 6141table 8 and must be fully earthed.

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5 Electrical Installation5.5 ‘S’ Plan System Schematic and Wiring Diagram

Figure 5-2: ‘S’ Plan system schematic - for Grant Aerona heat pump

Grant Aeronaheat pump

(with integralcirculating

pump)

Radiator

Pump

2 port zone valve(supplied)

Grant MonoWaveIndirect water cylinder

2 port diverter valve (not supplied)

Note: Connections areshown with the return

above the flow. Howeveryou can also connect the

flow above the return.

Figure 5-3: ‘S’ Plan wiring layout - for Grant Aerona heat pump

Cylinder DualThermostat (Top Coil)

Grant Aerona HeatPump ControlsConnection

230V50Hz

RoomThermostat

L N E

2

1

C C

12

1 2 3 4 5 6 7

N

HTGHW L

8 9 10

2

1 3

Zone valveDHW

Zone valveHTG

BlueBrown

Green/Yellow

Grey

Orange

Grey

Orange

BlueBrown

Green/Yellow

High limit Con trol

Junction box

Time controller

3

2

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6 Commissioning, Draining Down & Safety6.1 Filling the CylinderIMPORTANTBefore filling the cylinder check that theimmersion heater has not loosened intransit. Tighten as necessary using ashaped spanner. Stillsons or pipe gripsshould not be used.

1. Open all hot water taps.

2. Turn on the stop cock.

3. When water flows from all taps close the taps.

4. Allow system to stabilise for five minutes.

5. Open each hot water tap in turn to expel air from the system pipe work.

6. Check for leaks.

7. Manually operate Temperature andPressure Relief Valve (12) - Figures 2-3 or 2-4, to ensure free waterflow through discharge pipe. (Turn knob to left).

6.2 Draining DownSwitch the electrical power off(important to avoid damage to element).Isolate boiler from MonoWave unit.

Turn off the cold water supply valve(stop cock). Open hot water taps. Opendrain (16) - Figures 2-3 or 2-4. The unitwill drain.

6.3 Safety Cut-Out1. The safety cut-out operates if:

a. Wiring is incorrect.

b. The immersion heater thermostat orcylinder thermostat fails.

c. Thermostat is set too high.

2. Remember before resetting thesafety cut-out or altering thethermostat setting, isolate electricalsupply to the unit prior to removalof the electrical box lid.

3. Reduce thermostat setting andpress the reset button. Afteradjustments are completed, ensurethe lid to the electrical box isreplaced correctly and the retainingscrew is fitted.

4. If the problem persists, pleasecontact your installer in the firstinstance.

6.4 Cold Water Discharge fromTundishThere are two reasons why cold waterwill discharge from the tundish:

1. The pressure reducing valve hasmalfunctioned (This will cause alarge volume of water to flowthrough the tundish).

2. The Expansion relief valve is lettingby (This will cause a very lowvolume of water to flow through the tundish).

In both cases, identify the defectivecomponent and replace. All repairsmust be carried out by a competentperson.

6.5 Hot Water Discharge fromTundishThere are four reasons why hot waterwill discharge from the tundish:

1. Thermal cut-out has malfunctioned.

2. The control thermostat hasmalfunctioned.

3. The T & P valve is letting by.

4. The expansion vessel has failed orlost its charge.

In all cases, should a repair benecessary, the work must be carriedout by a competent person.

Isolate the cylinder from all electricalsupplies before commencingmaintenance work.

6.6 Expansion Vessel1. The expansion vessel is either

connected into the cold watersupply to the cylinder or screwedon top of the unit.

Note:No valve should be fitted betweenthe expansion vessel and thesupply pipe.

2. Ensure that the air charge in thevessel matches the pressure settingshown on the pressure reducingvalve.

3. The expansion vessel must beinstalled even if an accumulator isfitted.

4. The charge of the vessel must bechecked at every annual service.

6.7 Customer Handover1. Complete the Benchmark book

supplied with the Cylinder and leaveit with the User.

2. Explain the operation of the systemto the User, referring to Section 10of these instructions.

3. In particular, make the User awareof what to do if water is seen toflow from either the T&P Valve orExpansion relief Valve. Refer User tothe Information given in Section 10.

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7 Maintenance7.1 Servicing and Maintenance1. Servicing and maintenance must

only be carried out by a competentunvented hot water installer, or byGrant Engineering (UK) Limitedauthorised personnel.

2. Before any work whatsoever iscarried out on the installation, itMUST first be isolated from themain’s electricity supply.

Both the primary and secondarysystems will contain very hot waterthat will scald; therefore care shouldbe taken when opening any joints,seals or valves.

3. Only use spare parts authorised byGrant Engineering (UK) Limited. Theuse of unauthorised spare parts willinvalidate the warranty.

4. Drain the cylinder – When drainingthe cylinder, always switch off theboiler and the immersion heaterfirst. Turn off the water supply at themains stopcock.

Connect a hose pipe to the draincock (see Figures 2-3 or 2-4) androute it to a convenient gully. Openthe drain cock and all hot taps thatare served by the cylinder. Thecylinder may take several minutes to empty completely.

5. In hard water areas it may benecessary from time to time toremove and de-scale the immersionheater element. Replace the gasketeach time it is removed.

6. Remove the cartridge from thepressure-reducing valve (PRV).Check the strainer and if necessaryremove any debris from in front ofit. Replace the cartridge. Refer tosection 7.3 on the right.

7. Check the charge pressure in theexpansion vessel and top up asnecessary. The charge pressureshould be 3.0bar. Refer to section7.5 on the right.

! WARNING

8. Whilst the hose pipe is connected, thedrain cock open and with theimmersion heater removed, thecylinder may be flushed out to removeany debris, sand or lime scale particlesthat may have collected in the bottomby using a further hose pipeconnected to the cold water main.

9. Close the drain cock, disconnectthe hose, refit the immersion heaterand close all hot water taps beforereopening the stopcock. Allow thecylinder time to fill whilst checkingfor any leaks. Release any air fromthe system by opening each hotwater tap individually, starting withthe one furthest from the cylinder.

10. Manually lift the expansion relief andtemperature and pressure reliefvalve one at a time, every 12months (more frequently in hardwater areas) to prevent debris frombuilding up behind the valve seat.Whilst carrying out this operation,check that the discharge to wasteis unobstructed. Check that eachvalve seals correctly when released.As the valves are pre-calibrated,they require no further maintenance.

11. Finally switch on the mainselectricity supply to the immersionheater and the boiler. As the systemheats up, check again for any leaksand rectify as necessary.

7.2 Manifold AssemblyThe manifold assembly should not,under normal circumstance, require anymaintenance. During annual servicing itmay be necessary to inspect and/orclean the line strainer, the pressurereducing valve cartridge, expansionrelief valve cartridge. The frequency ofcleaning will depend on the local waterconditions.

7.3 Pressure Reducing Valve1. Isolate the cold water supply.

2. Unscrew the retaining nut of thevalve. The complete operatingmechanism, including the strainercan be removed.

3. Clean the filter mesh and thecartridge under running water.

4. Replace cartridge ensuring thatstrainer is correctly located andreassemble the unit. PressureReducing Valve cartridge andstrainer Part No. GCS07C - 3.0 bar.

7.4 Expansion Relief ValveCartridge1. Isolate the cold water supply.

2. Remove grub screw (Allen Key type) from body of valve andwithdraw valve ensuring not todamage O-ring.

3. Clean valve seat face and seating -do not scratch or damage eitherseat face or seating.

4. Refit in reverse order. Do notovertighten. Expansion valvecartridge Part No. GCS08.

7.5 Expansion Vessel1. Isolate the cold water supply.

2. Open hot water taps.

3. Drain cylinder to below tee piecetake off for expansion vessel flexiblehose.

4. Replace expansion vessel after firstchecking the air charge.

5. Close drain off cock and turn oncold water supply.

6. When water is flowing freely fromtaps close taps.

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8 Fault Finding Guide8.1 Intermittent Water Discharge

Intermittent Water Discharge from T & P Valve

Expansion VesselCharge Reduced

Test for correct operation. If water is still discharging, contact a competent Engineer

Thermostat Failure

Test Vessel andRecharge or Replace

Immersion ThermostatFailure

Primary CylinderThermostat

Faulty T & P Valve

Repair or ReplaceImmersion Thermostat

Repair or ReplaceThermostat

Replace T & P Valve

No

Yes

Yes Yes Yes

No No

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8 Fault Finding Guide8.2 Constant Water Discharge

Constant Water Discharge from T & P Valve

Expansion VesselCharge Reduced

Test for correct operation. If water is still discharging, contact a competent Engineer

Test Vessel andRecharge or Replace

Faulty T & P Valve

Faulty PressureReducing Valve

Replace T & P Valve

Replace PressureReducing Valve

No

YesYes Yes

Yes Yes

No No

8.3 No Flow from Hot Water Taps

No Flow from Hot Water Taps

Mains SupplyDisconnected?

Test for correct operation. If water is still not flowing, contact a competent Engineer

Open supply valve orwait for supply to be

reconnected

Mains SupplyDisconnected?

Mains SupplyDisconnected?

Clean Line StrainerRepair or Replace

Thermostat

No

YesYes Yes

Yes Yes

No No

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8.4 Cold Water Flow from Hot Water Taps

Cold Water from Hot Water Taps

Is Programmer callingfor Hot Water?

Check and Set HotWater setting

Is Motorised Valveworking?

Is Boiler working?

Is Cylinder Stat Calling for Heat?

Check Motorised Valvemotor and Micro-switch

Yes

No No No

No Yes

Yes

Yes

Yes

Test for correct operation. If water is still cold, contact a competent Engineer

Has Thermal Cut-OutOperated?

Check and Reset Button

Check and ReplaceCylinder Thermostat

No

Yes

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8 Fault Finding Guide8.5 Excessive Hot Water from Taps

Excessive Hot Water from Taps

Is Cylinder Thermostatset too high?

Reduce ThermostatSetting

Is System Wiringcorrect?

Correct Wiring as per Instructions

Is Cylinder ThermostatOperating?

Replace CylinderThermostat

No

Yes Yes

Yes

No

No

Test for correct operation. If water is still cold, contact a competent Engineer

Does Motorised Valveclose when Thermostat

is satisfied?

Repair or ReplaceMotorised Valve Motor

Repair or ReplaceMotorised Valve

Fault. Contact Engineer

Yes

No

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9 Spare Parts9.1 Spare Parts

Figure 9-1: Pressure Reducing Valve(Cartridge and Strainer) - 3 bar

Figure 9-3: Inlet Manifold includingpressure reducing valve, expansionrelief valve

Figure 9-2: Tundish

Part Name Part No.

Pressure Reducing Valve - 3 bar GCS32

Expansion Relief Valve - 6 bar GCS08

Flexible Hose - 3/4" BSPF x 3/4" BSPM GCS021/2" Temperature & Pressure Relief Valve 90˚C/7 bar GCS09

Tundish - 15mm/22mm Compression GCS10

Coil Control/Limit Thermostat GCS11

Immersion Heater Element - Cotherm type ELE14-IN-800-UNV GCS30

Drain Cock GCS14

Immersion Heater Thermostat - Cotherm type TSE GCS31

Motorised Valve GCS16

Expansion Vessel 12 litre nominal (125 model only)* (12 litre actual vol) - 3/4" BSPM connection GCS23

Expansion Vessel 19 litre nominal (125, 150 & 170 models)* (18 litre actual vol) - 3/4" BSPM connection GCS24

Expansion Vessel 24 litre nominal (200, 250 & 300 models)* (22 litre actual vol) - 3/4" BSPM connection GCS25

Expansion Vessel 35 litre nominal (400 model)* (35 litre actual vol) - 3/4" BSPM connection GCS28

1" BSPF x 3/4" BSPM Adaptor - for 35 litre Expansion Vessel GCS33

Inlet Manifold c/w 3 bar Pressure Reducing Valve and 6 bar Expansion Relief Valve GCS07

*All pre-charged to 3 bar

MonoWave Indirect Cylinder Spare Parts

Figure 9-4: Expansion Relief Valve(Complete) - 6 bar

Figure 9-5: Flexible Hose

Figure 9-6: Expansion Vessel

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10 User Instructions10.1 User Instructions1. Your Grant MonoWave HP

unvented hot water cylinder hasbeen designed to give many yearsof trouble-free service and is madefrom hygienic high grade stainlesssteel. The Indirect models includeone or two 3 kW electric immersionheaters for times when your heatpump is switched off, during thesummer for instance.

2. The flow temperature of the hotwater can be set to yourrequirements on the immersionheater up to 60°C and the indirectsystem dual thermostat up to 65°C.These temperatures should not beset any higher otherwise nuisancetripping of the high limit thermostatwill occur. If you are in any doubt,these adjustments should be bestleft to a qualified electrician.

3. When a hot tap is turned on theremay be a short surge of water, this isquite normal with unvented systemsand does not mean there is a fault.

4. When you first fill a basin the watermay sometimes appear milky. Thisis due to very tiny air bubbles in thewater, which will clear very quickly.

If water is seen to flow from either theTemperature & Pressure Relief (T&PValve) valve or the Expansion ReliefValve (EV) on the cylinder seek expertadvice immediately.

If the water is flowing from the T&PValve, immediately:

Shut off the electrical supply to theimmersion heater(s).

Shut down the boiler or other heatsources to the cylinder e.g. solar, heatpump, etc.

DO NOT SHUT OFF THE WATERSUPPLY TO THE CYLINDER.

Contact your installer to check thesystem.

IMPORTANTDo NOT tamper with any of the Safetycontrols fitted to the cylinder. If yoususpect a fault always contact aCOMPETENT installer who isQUALIFIED to work on unventedwater cylinders.

! WARNING

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11 Warranty11.1 The Grant CylinderWarrantyDear CustomerYou are now the proud owner of aGrant Cylinder from Grant Engineering(UK) Limited, which has been designedto give you years of reliable, trouble freeoperation.

Grant Engineering (UK) Ltd. guaranteesall electrical and mechanicalcomponents supplied with the cylinderfor a period of two years from the dateof purchase. In addition, the stainlesssteel used in the manufacture of thecylinder is guaranteed for a period oftwenty five years with the manufacturingprocess of the cylinder guaranteed fortwo years from the date of purchase,provided that the cylinder is installed infull accordance with the installationinstructions provided and the system isserviced after twelve months operation.(see Terms and Conditions).

ImportantPlease register your Grant cylinder withGrant UK within thirty days of theinstallation as follows.

Visit www.grantuk.com and follow thelinks to the 'Householder zone' whereyou can register your cylinder for afurther one year warranty (giving twoyears from the date of purchase). Thisdoes not affect your statutory rights.

Breakdown during theManufacturer’s WarrantyIf your Grant Cylinder should fail duringthe first two years, you must contactGrant Engineering (UK) Limited, who willarrange for the repair under the termsof their Warranty, providing that thesystem has been correctly installed andcommissioned, serviced (if older thantwelve months) and the fault is not dueto misuse, or the failure of any externalcomponents not supplied by Grant UK(e.g. pipework, etc.). This extended twoyear warranty only applies if the cylinderis registered with Grant UK within thirtydays of installation.

In the first Instance:Contact your installer or commissioningengineer to ensure that the fault doesnot lie with the system or any othercomponents, or any incorrect setting ofthe system controls.

If a Fault is Found:Ask your installer to contact GrantEngineering (UK) Limited, ServiceDepartment on 01380 736920 who willarrange for a qualified service engineerto attend to the fault.

Free of Charge Repairs:During the first two years no charge forparts or labour will be made providingthat the Cylinder has been installed andcommissioned correctly in accordancewith the manufacturer’s instructions,servised at twelve month intervals andthe cylinder was registered with GrantUK within thirty days of installation.Proof of ‘purchase’ date must beprovided upon request.

Chargeable Repairs:A charge will be made if the cause ofthe breakdown is due to any of thefollowing:

• Faults caused by the plumbing orheating system, external electricsand external components.

• The Grant Cylinder has not beencommissioned, or serviced inaccordance with the installationand servicing manual.

• The system has been installed forover two years.

Remember before you contactGrant:Please register your Grant cylinderwithin thirty days of the installation.

Terms of Manufacturer’s Guarantee1. The Grant Cylinder guarantee starts

from the date of purchase.

2. All electrical and mechanicalcomponents supplied with theGrant Cylinder are guaranteed for aperiod of two years. The stainlesssteel used in the manufacture of thecylinder is guaranteed for a periodof twenty five years with themanufacturing process of thecylinder guaranteed for two years.

3. The cylinder is registered within 30days of installation. Failure to do sodoes not affect your statutoryrights.

4. The Grant Cylinder must be installedby a competent/licensed installerand in accordance with the Codes ofPractice and Regulations in force atthe time of the installation.

5. The Grant Cylinder and itscomponents must not have beenmodified or tampered with.

6. The installation must be servicedevery twelve months as per theinstallation instructions. (Receiptsshould be kept as proof).

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7. The Grant Cylinder must beconnected to a mains water supply(installations utilising a private watersupply are not covered by thisguarantee).

8. Breakdown/failure due to lime-scalewill not be covered by thisguarantee.

9. The Grant Cylinder must not besited in a location where it may besubjected to frost.

10. All claims under this guaranteemust be made to Grant Engineering(UK) Ltd prior to any work beingundertaken. Proof of purchase anddate of installation must beprovided on request. Invoices forcall out/repair work by any thirdparty will not be accepted unlesspreviously authorised by GrantEngineering (UK) Ltd.

11. This guarantee is transferableproviding the installation is servicedprior to the dwelling’s new ownerstaking up residence. GrantEngineering (UK) Ltd must beinformed of the new owner’s details.

12. Grant Engineering (UK) Ltd willendeavour to provide prompt servicein the unlikely event of a problemoccurring, but cannot be heldresponsible for any consequence ofdelay however caused.

13. This guarantee applies to GrantCylinders installed on the UKmainland, Isle of Man and ChannelIslands only. Provision of in-warrantycover elsewhere in the UK issubject to agreement with GrantEngineering (UK) Ltd.

11.2 Extended WarrantyFor further peace of mind GrantEngineering (UK) Ltd offer the option toinsure all the components of your GrantCylinder for a further three years,following on from the two year productwarranty period. For a single premiumpayment (inclusive of InsurancePremium tax) you get five years ofprotection against breakdown costs. Atthe end of this period you will have theopportunity to continue this cover on anannual basis.

To access full details and an applicationform for this extended cover, first visitwww.grantuk.com.

Follow the links to the ‘HouseholderZone’, register your Cylinder for afurther one year product warranty(giving two years from the date ofpurchase), and then download theextended warranty details andapplication form.

Please note that this special offer is onlyavailable if the application form issubmitted to Bluefin Insurance ServicesLtd. within three month of theinstallation date.

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Notes

GRANT ENGINEERING (UK) LTDHopton House, Hopton Industrial Estate, Devizes, Wiltshire. SN10 2EU

Telephone: 01380 736920 Fax: 01380 736991Email: info@grantuk.com Website: www.grantuk.com