11-1Copyright 2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Chapter 11OPERATION

AND

COMMISSIONING OF APPLIANCES

11-2Copyright 2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Commissioning of appliances

Appliances are commissioned to ensure that they are performing safely and to their design requirements.

What commissioning involves (1)

• Checking that the installation complies with the manufacturer’s instructions, and applicable gas standards and regulations.

• Testing the installation for soundness.

• Purging the gas line to ensure all air is removed prior to lighting appliances.

• Checking that all burners and accessories are in their correct positions.

• Checking appliance operating pressure at test point.

11-3Copyright 2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

What commissioning involves (2)

• Checking the gas consumption of the appliance against its rated performance (using a gas meter if available).

• Checking operation of thermostats, safety devices and all accessories such as timers.

• Instructing the customer on the operation of the appliance and leaving the instructions with them.

It is advisable to record the commissioning results.

11-4Copyright 2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Types of cookers

• Food is usually cooked by:

1. boiling or frying on a hotplate

2. grilling

3. baking in an oven

• Types of cookers– Upright– Range– Elevated cooker– Wall oven– Built-in hotplate

11-5Copyright 2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Cooker operation—hotplate and grill

11-6Copyright 2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Cooker operation—oven

11-7Copyright 2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Oven—vitiation

Vitiation (flame suffocation) is caused by inadequate secondary air being available around a burner.

Causes of oven vitiation

1. Oven flue is blocked.

2. Gas rate is too high.

3. Burner angle is wrong or wrongly adjusted.

4. Oversized cooking utensil is used.

11-8Copyright 2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Instantaneous hot water services

Instantaneous hot water services

• Do not store water; the water is heated as it flows through the appliance.

• When a hot tap is turned on, the flow of water through the water section allows the gas to heat the water at a certain temperature owing to the constant flow.

Continuous flow hot water services

• Do not store water, the water is heated as it flows through the appliance.

• The temperature of the water remains constant even if the water flow changes via a computerised panel.

11-9Copyright 2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Storage hot water services

Consists of an insulated cylinder which stores the water at a preset temperature ready for use.

• Storage heaters are thermostatically controlled and when hot water is drawn from the top of the cylinder, cold water replaces it at the bottom.

• Water becomes less dense when heated and therefore rises and is replaced by cooler water.

• The thermostat is usually located close to the bottom of the cylinder and the cold water inlet.

• The thermostat reacts to the temperature change and full gas will flow to the burner. When the heated water reaches its preset temperature, it will stop the gas flow.

11-10Copyright 2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Storage water heaters

11-11Copyright 2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Room heaters

• The function of a room heater is to heat a room or area to a comfortable temperature and maintain comfortable conditions within that room or area.

• Comfort in a room depends on: i) temperature; ii) ventilation; iii) humidity

Methods of heating a room

• Radiant heat—travels in straight lines and does not give off its heat until it strikes a solid object.

• Convection heat—air becomes lighter when heated; the lighter air rises and is replaced by cooler air.

11-12Copyright 2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Commissioning room heaters

• Purge supply line.

• Check for leaks.

• Attach manometer—check and set working pressure.

• Check and adjust aeration of main burner.

• With main burner off, check and adjust pilot.

• When applicable, check operation of thermostat.

• Check appliance consumption against the data plate.

• Check time and operation of flame failure device.

11-13Copyright 2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Installation check

• Check the flue is fitted according the AS 5601 code and local authority codes.

• Check ventilation requirements.

• Check the operation of the flue.

• Inbuilt heaters must be secured and sealed as per manufacturer’s instructions.

• Check the operation of the fan.

• Check electrical operation.

1. Instruct customers on correct lighting procedure.

2. Ensure customers understand appliance operation.

11-14Copyright 2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Maintenance of appliances

To ensure that appliances perform to their maximum efficiency they need to be maintained at regular intervals.

Maintenance includes items such as cleaning the combustion chamber, grills and filters, and checking the appliance operation by recommissioning as previously described.

Individual appliances will have specific requirements, so you need to refer to the manufacturer’s instructions as well as observing the general guidelines above.

11-15Copyright 2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e

Commissioning appliances—Summary

• Appliances are commissioned to ensure that they are performing safely and to their design requirements.

• Check installation for compliance with AS 5601 and local authority requirements.

• Check appliance for correct installation, functioning and safe operation.

• Demonstrate operation of appliance to client.

11-16Copyright 2010 McGraw-Hill Australia Pty Ltd PowerPoint slides to accompany Puffett, Hossack, Stone, Burn & Miles, Gasfitting 2e