EnergyMaster Manual

INTEGRATED RENEWABLE & HEATING SOLUTIONS

underfloor heating

ground source heat pumps

air source heat pumps

solar thermal

rainwater harvesting

v01 © Nu-Heat

2

13

ENERGYMASTER THERMAL STORE MANUAL

Nu-HeatU N D E R F L O O R & R E N E W A B L E S

INTRODUCTIONIt is a condition of the warranty that the Commissioning Certificate included in the Handover Pack is completed and returned to Nu-Heat once the system is fully commissioned.The annual maintenance record at the back of the EnergyMaster User Guidemust also be completed at each yearly inspection.

This manual gives all the information needed to install your Nu-Heat EnergyMaster Thermal Store.

Building control must be notified of the fitting of this unvented thermal store.

Installation of an unvented thermal store must be carried out by a Competent Person or, failing that, the local building control authority must be notified of the proposed work before commencement and the completed installation must beinspected by a Competent Person.

In order for the process to be achieved quickly and easily the principle of operation should be understood. The followingpages have comprehensive diagrams showing the purpose of each component and its position in the installation. Parts supplied are listed - please note that pipework and some sundry fittings will be site supplied.

Attention to the advice given in this manual will help to ensure a trouble-free and effective installation. The requirementsof the relevant British Standards and IEE Wiring Regulations should always be met.

bs7671: 2008. requirements for electrical installations, iee wiring regulations, building regulations electrical safety (part p)

Electrical installation must be carried out by a Competent Person or, failing that, the local building control Authority must be notified of the proposed work before commencement and the completed installation must be inspected by aCompetent Person.

optional additional equipment

Where connections are shown to equipment that is not supplied by Nu-Heat, this is for guidance only. In all such casesthe supplier’s installation information should be checked before fixing and connecting the equipment.

Attention to the advice given in this manual will help to ensure a trouble-free and effective installation. The requirementsof the relevant British Standards, Water Regulations and other regulations should always be met.

If there is any aspect of the installation that you do not understand, please contact Nu-Heat Technical Support, quotingyour system reference number, for advice.

In line with the company policy of product development, Nu-Heat reserves the right to supply different components tothose shown.

This manual is the copyright of Nu-Heat. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means electronic, mechanical, photocopying, recording or otherwisewithout prior written permission of Nu-Heat.

EnergyMaster Manual

page contents

2 Introduction

4 Cylinder storage on site

4 Positioning the cylinder

4 Cylinder connections

5 Performance

5 Mains water supply

5 Pipework

6 Components

9 Temperature/pressure relief valve discharge

10 Immersion heater control

10 Thermal cut-outs

11 Connection position of secondary hot water loop

12 EnergyMaster hot water supply

13 Cleansing, filling, flushing and commissioning the cylinder

15 Draining the cylinder

15 Hard water precautions

15 Troubleshooting, warranty and servicing requirements

CYLINDER STORAGE ON SITEThe cylinder should be stored under cover, in a dry place. It may be tilted forhandling around site, but beware of laying the cylinder horizontally as this couldinadvertently cause damage to the connection tappings.

POSITIONING THE CYLINDERThe cylinder location will have been discussed as part of the system designprocess, and the agreed position will be noted on the A3 System Illustration andManifolds. Space must be provided for access to allow any future maintenanceand replacement work

Please note the cylinder weight in order to ensure that the floor on which it sitsis structurally sufficient.

EnergyMaster 210 litre 260 kg

EnergyMaster 210 litre solar 263 kg

EnergyMaster 300 litre 365 kg

EnergyMaster 300 litre solar 368 kg

EnergyMaster 400 litre solar 474 kg

CYLINDER CONNECTIONSPlease see the A3 System Illustration and Manifolds supplied for the overallplumbing scheme.

A Product Data Sheet is provided in the Handover Pack show all the fittings supplied and the purpose of each tapping.

The cylinder relief valve shall not be used for any other purpose

Note: Push fit fittings must not be connected to the stainless steel tails as thegrab ring will not grip the stainless steel.

EnergyMaster Manual

PERFORMANCEThe EnergyMaster cylinder is designed to provide the following maximum flowrates when raising mains cold water through 40⁰C at full duty:EnergyMaster 210 litre (incl. solar) 27 litres/minute

EnergyMaster 300 litre (incl. solar) 40 litres/minute

EnergyMaster 400 litre solar 40 litres/minute

MAINS WATER SUPPLYThe cylinder should take its mains water feed after the supply to the kitchen, butbefore all other cold water draw-offs, above the stop cock. If the mains pressureexceeds 3.5-bar it should be limited to this figure by a pressure reducing valve(not supplied) equal to the size of the connecting pipework, fitted after the incoming stopcock and the supply to the kitchen and before any draw-off points.

A mains water input of up to the maximum performance figures stated above (or double for dual cylinders) is required at minimum static pressure of 2-bar.Where the supply is inadequate but the incoming mains pressure is over 2-bar it can be boosted with a purpose designed accumulator vessel. Please contact Nu-Heat for details. A non-return valve and expansion vessel is supplied tomeet water regulations.

PIPEWORKThe minimum size of copper pipework to be used for mains water connectionsto and from the cylinder is:

EnergyMaster 210 litre (incl. solar) 22mm

Dual EnergyMaster 210 litre (incl. solar) 22mm

EnergyMaster 300 or 400 litre (incl. solar) 28mm

Dual EnergyMaster 300 or 400 litre (incl. solar) 35mm

COMPONENTSenergymaster cylinder

Please refer to your A3 System Illustration and Manifolds for your specificplumbing schematic.

Please note: installation of the EnergyMaster thermal store is notifiable work.

The EnergyMaster cylinder stores water for both the floor heating and the production of domestic hot water. If the temperature of the water in the cylinder falls below the level set on the cylinder thermostat, the boiler is turnedon and hot water is circulated into the body of the cylinder to replenish thestore. A secondary over-temperature cut out protects against failure of the dual cylinder thermostat/primary over-temperature cut-out.

If installed with a solar thermal system, the solar pump will be brought on toheat the cylinder when the hot water temperature in the cylinder drops. If thereis any shortfall this will be made up by the boiler which is called on by the cylinder thermostat.

In larger properties either a larger cylinder, or twin cylinders may be recommendedto ensure an adequate supply of hot water.

1. Automatic air vent

2. Secondary over-temperature cut out

3. Pressure relief valve (factory fitted)

4. Chrome pipework assembly (trim to length)

5. Hot water blending valve

6. Flow switch

7. Dual cylinder thermostat/primary over-temperature cut-out

8. 3kW immersion heater

expansion vessel

The EnergyMaster cylinder is supplied with a 2 litre expansion vessel. This vesselabsorbs the small amount of expansion in the domestic hot water pipeworkwhen the system is hot and must be checked and set to 4-bar when the system is cold, at commissioning stage.

non-return valve

A non-return valve is supplied to comply with the water regulations and preventbackflow. It must be positioned in the flow to the EnergyMaster cylinder after the cold tee off to the kitchen, in line with water regulations. See A3 System Illustration and manifolds for details.

2545

65

1

2

3

4

5

6

7

8

COMPONENTS cont.auto air vent – operation and maintenance

For rapid venting when filling the cylinder remove both caps and depress thevalve under the red cap with a screwdriver. Replace the red cap when the system is full.

During normal operation the cylinder is vented by leaving the black bleed caploose, this allows stray pockets of air to escape automatically and should bechecked regularly.

Important: to prevent cylinder collapse when draining down the system ensurethe rapid venting valve is depressed or the air vent connections loosened.

pressure relief valve

If, in the unlikely event of failure of all other safety devices, the cylinder reaches excessively high pressure then water will be discharged by this valve.The outlet from this valve should be safely taken to waste via copper pipe (see Temperature/pressure relief valve discharge section). The valve should be manually operated during the annual servicing by turning the knob in order tocheck that it is free to function.

shunt pump, valves and bends

Mounted on the EnergyMaster cylinder and controlled by the flow switch, thispump circulates stored boiler water through the domestic hot water heat exchangergiving mains-pressure hot water on demand. Important: Arrow indicates directionof water flow.

flow switch

The flow switch detects the flow of water into the EnergyMaster cylinder’s internalheat exchanger. The switch operates the shunt pump, ensuring that the heat exchanger can work at its maximum capacity. The flow switch must be fitted inthe orientation shown, with the arrow pointing upwards.

isolating valve and strainer

The in-line 22mm isolating ball valve with filter is fitted on the cold mains supply to the EnergyMaster cylinder. It prevents grit getting into the cylinder and enablesthe cold water supply to the cylinder to be shut off if necessary. It must be fittedwith the trap below the pipework. Restrict the incoming mains cold water flow rateto between 22 and 27 litres/min. for 210 litre cylinders, 36 and 40 litres/min. for 300and 400 litre cylinders. For dual cylinders the flow must be equal to each cylinder.

EnergyMaster Manual

Rapid vent screwBleed screw

Pressure relief valve

Shunt pump,valves andbends

Flow switch

Isolating valve and strainer

COMPONENTS cont.cylinder zone valves

Two cylinder zone valves are supplied, and both must be fitted. One is controlledby the dual cylinder thermostat/over-temperature cut-out. The second is controlledby the secondary over-temperature cut-out at the top of the cylinder. It is a requirement of building regulation G3 that, with unvented thermal stores, thereare two independent over-temperature cut-outs, and they must each operate an independent valve.

expansion vessel and filling loop assembly

The expansion vessel forms part of the filling loop assembly. It accommodatesboiler and cylinder water expansion when the system is hot. Use in addition toany internal system boiler expansion vessels to accommodate the additional expansion of the EnergyMaster cylinder water volume. It is important to note:before fitting the expansion vessel the air pressure must be reset. Refer to A3 System Illustration and Manifolds.

1. Connection to boiler primaries

2. Pressure gauge

3. Pressure relief valve

4. Discharge to waste

5. Non-return valve

6. Isolating valves (2)

7. 15mm cold mains in

8. 15mm Pressure reducing valve adjusted to 1-bar maximum fill pressure

9. Air valve connection (for charging and checking pre-charged air pressure)

10. Expansion vessel

9 10

6 8

1 2 3 4 5 6

7

EnergyMaster Manual

PRESSURE RELIEF VALVE DISCHARGEThe pipe work that takes any discharge from the pressure relief valve should befitted in copper.

The pipe outlet should be taken to a safe place, as any water/steam released is ascald hazard. Such a safe place would be below a fixed grate to a trapped gully.Note that the discharge will be either very hot water or steam that will causedamage to certain plastics or asphalt, etc.

The pipe work should be sized so as not to restrict the discharge. The diameterof pipe connected to the pressure relief valve (D1) should be at least as large asthe outlet of the valve, and the pipe run must be no more than 600mm length before the tundish. The pipe should drop continuously away from the valve.

The tundish outflow should be made in at least the next largest size up from theinlet. If the length of pipe is greater than 9m then the next size up is required (i.e.if a 22mm outflow, then 28mm pipe work), and if longer than 18m then two sizeslarger, and so-on. Any bends and elbows also present a pressure drop, and thesemust be accounted for by assigning an equivalent pipe length as given in thetable below.

1/2” Valve Pipe size (mm)

22

28

35

Max. pipe length basedon straight length (m)

9

18

27

Equivalent resistance ofbend or elbow (m)

0.8

1.0

1.4

There must be a straight drop of300mm below the tundish.Safety device

(e.g. temperaturerelief valve) 600mm

max.

300mm min.

Metal discharge pipe (D2) fromtundish with continuous fall

Metal discharge pipe (D1) fromtemperature relief valve to tundish

Tundish

Discharge below fixed gratingor suitable alternative

Fixed grating

Trapped gulley

IMMERSION HEATER CONTROLAn immersion heater is supplied with the cylinder to provide a back-up in case,say, of oil or LPG running out. Please see the A3 Underfloor Heating ControlSystem drawings for wiring information.

The immersion heater must be installed with a fuse as rated by the manufacturer,and comply with the relevant electrical standards.

Note: The immersion heater supplied is fitted with a thermal cut-out. This isan essential safety requirement, and immersion heaters without thermalcut-outs must not be used.

THERMAL CUT-OUTSAll cylinders are provided with a dual ‘stat with over-temperature cut-out, and a second over-temperature cut-out thermostat (high limit stat) to prevent thecylinder from exceeding 90˚ C. These must operate two separate cylinder zonevalves in order to comply with Part G of the building regulations.

EnergyMaster Manual

CONNECTION POSITION OF SECONDARY HOT WATER LOOP

2545

65

Auto air vent

Hot water to taps

Mains cold water

Underfloor heating

Immersionheater

Drain-offFlow

Return

Secondary Hot Water Loop return – supplied separately

NRV

NRV

ENERGYMASTER HOT WATER SUPPLYdomestic hot water temperature blending valve

The domestic hot water blending valve should be fitted to the EnergyMastercylinder. It is supplied pre-set to 43˚C however BS6700 recommends that waterbe distributed at no less than 45˚C. If a hot water loop is to be used then theHSC’s Legionnaires’ disease: The control of legionella bacteria in water systems –Approved Code of Practice and Guidance says that this temperature should be50˚C or more.

If the temperature of circulation necessary to achieve this poses a significant riskof scalding then the temperature should, in addition, be blended down as closeto the output as possible, especially at bath taps which must be limited to 48˚Caccording to Building Regulations Part G3. These additional blending valves arenot supplied by Nu-Heat.

In order to set a different temperature, do as follows:

• Remove the screw securing the knob to the valve.

• Remove both the knob and the locking ring.

• Replace the knob temporarily.

• Open a tap and adjust the set temperature of the valve as required (anti clockwise to increase and clockwise to decrease).

• Remove the knob and refit the locking ring.

• Locate the tab on the inner face of the knob.

maintenance of the domestic hot water blending valve

The valve should be checked and cleaned annually. If the cylinder’s domestichot water pipe is hot and the blending valve outlet pipe is cold it is possible thatthere is a build up of scale within the valve. To strip down the valve and clean:

• Drain the domestic hot water system.

• Isolate the valve and remove the knob and locking ring.

• Unscrew the large hexagonal cap and slide out the interior parts of the valve.(Note the orientation of the parts to aid reassembly).

• After cleaning and reassembling, the valve should be reset and tested.

Domestic hot water temperatureblending valve (210 litre)

35

MIN

MAX

65

Domestic hot water temperatureblending valve (300 litre)

EnergyMaster Manual

CLEANSING, FILLING, FLUSHING AND COMMISSIONING THE CYLINDEROnce installation is complete the system must be cleansed to remove any solder or flux residues, or any other foreign matter. Cleansing of the DHW system will not require a significant volume of fluid.

Any cleansing agent must not have a chlorine level exceeding 250mg/litre. This solution must be thoroughlyflushed through, as high levels of chlorine are corrosive to the cylinder.

Filling the domestic hot water side:

• Before filling, check expansion vessel charge is at 3.5bar.

• Open all outlets on the domestic hot water circuit. Open the main supply to the unit.

• Flush the unit through until all air is expelled.

• Close hot outlets and open all cold outlets connected after the pressure reducing valve for the incoming mains. Flushthrough until all air is expelled.

• The domestic water side of the system is now full of water. Check for any leaks on pipework or joints. It is the installersresponsibility to check all fittings, including those that are fitted to the unit.

Filling the main cylinder volume:

The boiler filling loop can be used to fill the cylinder. Whilst filling the cylinder it is important that the fast purge valveunder the red cap of the Automatic Air Vent is depressed. Alternatively the air vent may be removed until the cylinder isnearly full, and then the fast purge should be used.

CLEANSING, FILLING, FLUSHING AND COMMISSIONING THE CYLINDERcommissioning the energymaster cylinder

System settings

2545

65

1. Set the boiler thermostat to a mini-mum of 75˚C so that it is higher thanthe cylinder thermostat. Ensure theboiler output rating is set to maximum. If resetting is necessary,please refer to manufacturer’s instructions.

2. Set the cylinder thermostat to 65˚C(maximum).

3. Set the cylinder shunt pump to constant curve speed 3 if using anUPS2 pump (see below). If using a Magna pump, set to 3m head (seebelow for details).

4. Set the boiler pump to maximum.

Note: When the system has been running for at least 60 minutes, thetemperature difference between theflow and return pipework at the boilershould be approximately 11˚C. If it ismuch higher than this, check that theboiler pump is set to maximum, (if usinga system boiler the pump will be insidethe boiler and may not be adjustable).If it remains high, please call Nu-HeatCustomer Support for advice.

The cylinder must be thoroughlychecked in accordance with the Commissioning Checklist and WarrantyApplication form in the HandoverPack. This must be fully completedduring the commissioning process andreturned to Nu-Heat for registration.

No warranty can be issued withoutthe return of the completed Commissioning Checklist to Nu-Heat.

Pump model

Grundfos UPS2

Grundfos Magna

Press to cycle throughthe options until constant pressure mode is lit

Press to cycle throughthe options until IIIIII is lit continuously (fixed speed mode, speed III)

Optimum setting

Then use and to set the pressure to ‘3’ (3m head)

2. 3. 4.

EnergyMaster Manual

DRAINING THE CYLINDERDraining the Domestic Hot Water side of the cylinder:

• Ensure that the mains is isolated

• Open a tap, or to release the pressure from the system use a tap that is higher in the property than the cylinder.

• Leaving the tap open, and using a bucket to collect the water, carefully remove the blanking cap from the isolating valveand strainer on cold mains inlet and use this to drain the hot water side. Remember to close the butterfly valve to prevent flow of fresh water from the mains.

• Once the cylinder is empty remember to close the tap.

• Refill as per filling instructions.

Draining the main cylinder volume:

• Be aware that boiler water flows directly into the cylinder.

• If required, isolate manifolds and all other circuits to prevent draining down of whole system.

Note: It is essential during draining that either the red cap fast purge on the auto air vent is depressed, or the autoair vent completely removed from the cylinder.

Failure to do so may collapse the cylinder under the weight of water.

• Connect a hose to the cylinder drain off valve. Open the valve and drain the cylinder to waste.

• Refill via the boiler filling loop as per previous instructions. The inhibitor levels in the system will need to be checkedafter re-filling.

HARD WATER PRECAUTIONSIf the property is in a hard water area (where Ca CO3 exceeds 200ppm), a softener should be used to prolong the life of thecylinder heat exchanger. If the cylinder heat exchanger should scale up, a proprietary flushing solution should be used witha flushing pump between the cold mains in and the hot outlet. Make sure that the flushing agent is fully dispersed afterwards.

Any cleansing agent must not have a chlorine level exceeding 250mg/litre. This solution must be thoroughly flushedthrough, as high levels of chlorine are corrosive to the cylinder.

TROUBLESHOOTING, WARRANTY AND SERVICING REQUIREMENTSThe EnergyMaster cylinder features a 25 year warranty. In order to validate the warranty, the EnergyMaster must be servicedannually. For full details of the EnergyMaster troubleshooting, servicing requirements and a maintenance log, please referto the EnergyMaster Cylinder User Guide.

Heathpark House, Devonshire Road,Honiton, Devon EX14 1SDTel: 01404 549770Fax: 01404 549771Web: www.nu-heat.co.ukEmail: info@nu-heat.co.uk

Nu-HeatU N D E R F L O O R & R E N E W A B L E S

If there is any aspect of the installation that you do not understand, please contact Nu-Heat Technical Support for advice.

All illustrations and diagrams in this manual are the property of Nu-Heat. All rights reserved. No part of this publication may be reproduced, stored in a retrieval system, or transmitted in any form or by any means electronic, mechanical, photocopying, recording or otherwise without prior written permission of Nu-Heat.

DESIGN | INNOVATION | EXPERTISE | SERVICE

2

0

13

4