1. Pt.2 Types of Domestic Central Heating Systems

What is a major drawback of the one pipe gravity system?

• High efficiency boilers

• Quick heating of radiators

• Each radiator progressively cools down

• High installation cost

Which system has gravity circulation to the hot water circuit but pumped circulation to the heating circuit?

• C plan two pipe semi gravity

• Two pipe semi gravity

• One pipe gravity system

• Fully pumped systems

What is a disadvantage of the two pipe semi gravity system?

• All heat emitters reach the same temperature

• Cheaper to run

• Uncontrolled heat

• Compliant to Building Regulations part L

What makes the C plan two pipe semi gravity system compliant with Building Regulations part L1b?

• Restricted heat control

• Boilers tend to be lower efficiency

• Incorporates a thermo mechanical thermostat

• It is not fully pumped

What is an advantage of fully pumped systems?

• Boiler position needs to be lower than the cylinder

• Longer heat-up times

• More economical on fuel and operating costs

• Only suitable for small properties

What does the three port mid-position valve control in a Y plan system?

• The pressure within the boiler

• The flow of water to the hot water cylinder and heating circuit

• The speed of the pump

• The temperature of the radiators

What is the purpose of an automatic bypass in a central heating system?

• To increase system pressure

• To decrease system pressure

• To allow water to flow through the boiler when circuits close down

• To stop the boiler from functioning

What is aeration a big cause of within a central heating system?

• Increased efficiency

• Corrosion

• Decreased noise

• Improved heat distribution

What does a sealed system incorporate that an open system does not?

• A feed and expansion cistern

• A simpler filling connection

• A sealed expansion vessel

• A higher pressure relief valve

What is the primary function of a thermostatic radiator valve (TRV) in a central heating system?

• To regulate the flow of water based on the ambient temperature

• To increase the pressure within the system

• To prevent water from flowing back into the system

• To manually control the temperature of each radiator