CENWAT Boiler Operation and Controls

Question 1

What is the minimum efficiency rating required for a new gas boiler installation under current Building Regulations Part L in England?

Accepted Answer

92% ErP

Answer

86% ErP

Answer

89% ErP

Answer

95% ErP

Question 2

At what flue gas temperature does a condensing boiler begin to recover latent heat from the products of combustion?

Accepted Answer

57 degrees C (dew point)

Answer

100 degrees C

Answer

80 degrees C

Answer

40 degrees C

Question 3

What is the purpose of the boiler interlock in a central heating control system?

Accepted Answer

To prevent the boiler firing when there is no demand for heat

Answer

To lock the boiler room door for safety

Answer

To connect multiple boilers together

Answer

To lock the gas supply during servicing

Question 4

Which component in a condensing boiler is specifically designed to extract additional heat from flue gases?

Accepted Answer

Secondary heat exchanger

Answer

Primary heat exchanger

Answer

Fan assembly

Answer

Gas valve

Question 5

According to the Boiler Plus legislation (England), what additional control is required when installing a regular boiler?

Accepted Answer

Time and temperature control of heating and hot water as separate zones

Answer

A smart thermostat only

Answer

A weather compensation controller only

Answer

Flue gas heat recovery only

Question 6

What is the correct procedure if the condensate pipe from a condensing boiler freezes?

Accepted Answer

Apply warm water to the frozen section of the external condensate pipe

Answer

Replace the boiler immediately

Answer

Disconnect the condensate pipe and let it drain freely

Answer

Bypass the condensate trap