CCN1 Gas Appliance Installation and Commissioning

Question 1

What is the minimum distance a room-sealed balanced flue terminal must be from an openable window or air vent?

Accepted Answer

300mm

Answer

BS 5440 Part 1 requires a room-sealed appliance flue terminal to be at least 300mm from any openable window, air vent, or opening to prevent combustion products from re-entering the building.

Question 2

Which document must be completed and left with the customer after commissioning a new gas boiler?

Accepted Answer

Benchmark commissioning checklist

Answer

The Benchmark commissioning checklist must be completed and handed to the customer as proof that the appliance has been correctly installed, commissioned, and is operating to the manufacturer's specification.

Question 3

What type of gas appliance does NOT require a permanent air vent in the room where it is installed?

Accepted Answer

Room-sealed (balanced flue) appliance

Answer

Room-sealed appliances draw combustion air directly from outside and discharge products of combustion outside, so they have no effect on the room's air quality and do not require a permanent air vent.

Question 4

What is the correct standing (static) gas pressure for natural gas at a domestic meter outlet?

Accepted Answer

21 mbar

Answer

The standard standing pressure for natural gas at a domestic meter outlet is 21 mbar, measured with no gas flowing; working pressure when gas is flowing is typically 20 mbar.

Question 5

Which primary legislation requires all gas work on domestic premises to be carried out by a Gas Safe registered engineer?

Accepted Answer

The Gas Safety (Installation and Use) Regulations 1998

Answer

The Gas Safety (Installation and Use) Regulations 1998 (GS(IU)R) specifically require that all gas work on domestic premises must be carried out by a competent Gas Safe registered engineer.

ACS CCN1 Practice Test

ACS CCN1 Practice Test

CCN1 Gas Appliance Installation and Commissioning