Appliance Installation Flashcards
6 cards from real ACS practice questions. Tap to flip, then mark Knew It or Still Learning — missed cards come back until you master them.
Read the first 6 Appliance Installation flashcards as text
What is the minimum separation distance between a gas meter box and an electricity meter box when installed externally on a building?
Answer: 150mm horizontally or as specified in GS(IU)R 1998 and network operator standards (typically 150–300mm)
Gas and electricity meters must be separated by sufficient distance to prevent gas accumulation near electrical equipment that could cause ignition — network operator standards specify the precise separation required.
Which type of pipe is commonly used for internal domestic gas installation in the UK?
Answer: Copper or corrugated stainless steel (CSST) pipe with compression or press-fit fittings
Internal gas pipework is typically copper or CSST installed with appropriate fittings; yellow MDPE is used externally and underground but not internally.
What does a 'boiler interlock' ensure in a central heating system?
Answer: The boiler fires only when there is a demand for heat from a room thermostat or timer, preventing unnecessary operation
An interlock ensures the boiler only fires when there is genuine heating demand, improving efficiency and complying with Building Regulations Part L requirements for modern heating systems.
What is the correct procedure for purging air from a new domestic gas installation before lighting the appliance?
Answer: Purge at a suitable point using the procedure in IGE/UP/1 or the appliance manufacturer's instructions, verifying with a gas detector that air has been replaced
Air must be purged from new or recommissioned pipework to ensure the gas/air mixture in the pipework is replaced with pure gas before the appliance is lit, following the procedure in IGE/UP/1.
What is the purpose of a gas pressure test point downstream of the meter?
Answer: To allow the engineer to measure gas pressure during and after appliance operation to verify adequate supply throughout the system
Test points allow measurement of dynamic gas pressure (with appliances running) to verify that the pipework delivers adequate pressure to all appliances simultaneously without excessive pressure drop.
Under BS 6891, what is the maximum allowable pressure drop across a domestic gas installation during a tightness test?
Answer: 1 mbar over a defined test period after the permitted stabilisation time
BS 6891 specifies that after the permitted stabilisation period, a tightness test on a domestic installation should show no pressure drop greater than 1 mbar — any greater drop indicates a leak.