Central Heating System Quiz

What is the maximum distance between the open vent and cold feed on an H-frame?

• 100mm

• 125mm

• 150mm

• 175mm

Answer explanation

The maximum distance between the open vent and cold feed on an H-frame is specified as 150mm. This ensures proper functionality and efficiency in the system, making 150mm the correct choice.

What is the most suitable position for the installation of an expansion vessel within a central heating system?

• On the flow pipe near to the boiler

• On the return pipe near to the boiler

• On the cold feed pipe to the system

• On the open vent pipe

Answer explanation

The expansion vessel should be installed on the return pipe near to the boiler to effectively manage pressure changes and accommodate thermal expansion, ensuring optimal system performance.

What item allows the individual control of hot water and central heating timing?

• Boiler

• Two port valve

• Room stat

• Programmer

Answer explanation

The programmer is the device that allows users to set specific times for heating and hot water, providing control over when these systems operate. This makes it the correct choice for managing heating schedules.

An S-plan system has what type of valve controlling the hot water and central heating circuits?

• Three port valve

• Mid position valve

• Two port valves

• Gravity circulation

Answer explanation

An S-plan system uses two port valves to control the flow of hot water to either the heating circuit or the hot water circuit, allowing for efficient operation without the need for a mid-position valve.

When the zone valve closes, the boiler switches off and the circulator stops running, but the programmer is still on; this is known as…

• Boiler interlock

• Boiler cycling

• Boiler overheating

• Boiler lockout

Answer explanation

When the zone valve closes, it signals the boiler to stop heating, which is a function of the boiler interlock system. This ensures that the boiler and circulator only operate when needed, preventing unnecessary energy use.

Look at the image in the Question above. How is the heating system piped?

• One-pipe

• One-pipe reverse return

• Two-pipe

• Two-pipe reverse return

Answer explanation

The heating system is piped as a two-pipe system, which consists of separate pipes for supply and return of water, allowing for more efficient heating and better temperature control compared to one-pipe systems.

What is the recommended maximum surface temperature for heat emitters in schools and NHS properties?

• 42 degrees

• 43 degrees

• 45 degrees

• 53 degrees

Answer explanation

The recommended maximum surface temperature for heat emitters in schools and NHS properties is 43 degrees. This limit helps ensure safety and comfort for occupants.

What is the minimum distance required between the floor and the bottom of a radiator?

• 100mm

• 150mm

• 200mm

• 250mm

Answer explanation

The minimum distance required between the floor and the bottom of a radiator is 150mm. This clearance ensures proper airflow and efficient heating, making 150mm the correct choice.

The grade of copper used in microbore central heating systems is…

• R250

• R290

• R220

• R230

Answer explanation

The grade of copper used in microbore central heating systems is R220, which is specifically designed for this application due to its balance of strength and flexibility, making it suitable for tight spaces.

A half-hard straight length of copper is…

• R290

• R250

• R220

• R200

Answer explanation

A half-hard straight length of copper is classified as R250, which indicates its specific mechanical properties. The other options, R290, R220, and R200, represent different hardness levels.