Quiz - Domestic Gas
Complete this Domestic Gas Test to see how your knowledge rates and what you can improve upon!
The Test:
1. What is the approximate amount of air required for complete combustion of Natural gas?
a) 1 volume of air for 1 volume of gas
b) 2 volumes of air for 1 volume of gas
c) 10 volumes of air for 1 volume of gas
d) 20 volumes of air for 1 volume of gas
2. What are the visual indications that incomplete combustion is taking place?
a) Yellow flame, soot deposits in and around the burner and flue exit
b) Thermocouple is too hot and glows red
c) Appliances get too hot
d) Stable blue flames with clearly defined inner and outer cones
3. Which of the following are symptoms of Carbon Monoxide poisoning?
a) Pale face complexion
b) Nose bleeds
c) Headache, nausea, lethargy, red complexion
d) Headache, blocked nose, sneezing, red complexion
4. Which of the following is not a suitable jointing method for copper pipework serving a gas installation?
a) Capillary action solder joints
b) Press fittings
c) Compression fittings (surface mounted)
d) Compression fittings in voids
5. What is the permissible pressure loss for a domestic gas installation (existing installation with appliances fitted and no smell of gas etc), where the gas meter is remote and not included in the tightness test e.g. an individual flat with ECV and supplied via a communal meter?
a) 2mbar
b) 4mbar
c) 6mbar
d) 8mbar
6. The operating pressure required at the outlet of the meter (U6/G4/E6) should be controlled to which of the following?
a) 21mbar precisely for all flows
b) 21mbar ± 1mbar for all flows
c) 19mbar at maximum flow rate
d) A minimum of 19mbar at maximum flow rate of ≥6m3/hr
7. The purpose of a range rated appliance is which of the following?
a) So that the appliance can provide flexible heat outputs
b) So that the appliance can be set below its maximum to prevent overheating
c) So that the gas operative can decide what pressure to set the appliance at
d) To meet the specification for a CE mark
8. On a natural draught open-flue, the function of the primary flue is which of the following?
a) To create initial flue draught
b) To prevent downdraught from the secondary flue affecting combustion
c) To transfer products of combustion and dilutant air to atmosphere
d) To prevent the flue from becoming blocked by birds
9. Above what cross-sectional dimension of flue is it unnecessary to fit a flue terminal?
a) 150mm
b) 170mm
c) 175mm
d) 200mm
10. In the absence of specific manufacturer’s instructions, if a boiler is located in a compartment what is the minimum distance from the boiler for combustible materials?
a) 25mm
b) 50mm
c) 75mm
d) 100mm
11. Which of the following represents a correct requirement for a hearth serving a gas fire?
a) It should have a minimum thickness of 25mm
b) It should extend at least 500mm from the back plane of the appliance
c) It should extend at least 150mm beyond the edge of the incandescent material
d) The incandescent material should be at least 125mm from the carpet
12. When sampling the combustion products in a room-sealed appliance, where should the sample probe be located?
a) With the sample tip at least 200mm into the secondary flue
b) In the centre of the flue exit
c) 200mm inside the exhaust outlet and where CO2 concentrations read at the highest steady level
d) Directly above the outlet grille
13. When checking combustion performance with an electronic combustion gas analyser the appliance being checked needs to run in which of the following conditions?
a) At a constant maximum rate during the sample period
b) At a constant minimum rate during the sample period
c) At normal operating conditions on modulating appliances
d) Any of the above
14. Which of the following types of appliances are suitable if an electronic combustion gas analyser is to be used to determine the level of servicing is required?
a) Open-flued or room-sealed boiler
b) Room-sealed heaters connected to a SE-Duct flue system
c) Back boiler unit
d) Live fuel effect room-sealed gas fire
