CENTRAL HEATING MOCK EXAM

In a two pipe system the

• flow and return pipework are separated

• flow and return pipework are mixed

• return water is at the same temperature as the flow water

• return water temperature is higher than the flow water.

Which of the following systems does the statement apply to? ‘The temperature of the last radiator on the circuit will be cooler than the first radiator.’

• Two pipe system.

• One pipe system.

• Two pipe reverse return system.

• Microbore system.

What is the normal size of an open vent pipe to a fully pumped heating system, in a domestic property?

• 10 mm.

• 15 mm.

• 22 mm.

• 28 mm.

The connection of an open vent pipe and a cold feed pipe, can be made to a fully pumped system using

• an automatic air vent

• an injector tee

• an air separator

• a diverter valve.

A zone valve/two port valve in a pumped heating circuit is designed to

• isolate the circuit when the desired temperature is reached

• permit the system to be heated to temperatures above 100°C

• stop the pump vibrating on its fixing mountings

• prevent water from the flow and return pipes mixing.

The main purpose of the vent pipe installed on a heating circuit is to

• fill the system with water

• provide hot water to the feed and expansion cistern

• introduce air into the system

• protect the system in the event of over-heating.

Refer to Figure 1. Which one of the following components is indicated by the British Standard symbol shown?

• Air Inlet Valve.

• Draining Valve.

• Double Check Valve

• Pressure Relief Valve.

Refer to Figure 2. Which one of the following components is indicated by the British Standard symbol shown?

• Drain off valve.

• Air Inlet Valve.

• Servicing Valve.

• Pressure Relief Valve.

A three port mid position diverter valve...

• provides priority circulation to the hot water circuit

• provides priority circulation to the heating circuit

• feeds both the hot water and heating circuits simultaneously

• is used to discharge water from the system if it overheats.

Which one of the following can be fitted with a remote sensor?

• Diverter valve.

• Solenoid valve.

• Motorised valve.

• Thermostatic radiator valve.