Air Source heat pumps extract heat from ambient air.

The refrigerant circuit then takes the low temperature energy and upgrades it in

the vapour compression cycle to provide a higher temperature heat source that

can be used to heat a heating circuit or a hot water cylinder.

The correct selection of an air source heat pump to match it's heat output to the

requirements of a building on the winter design day it vital to a successful

installtion.

 

The efficiency of a heat pump is higher if a low temperature heating circuit is used.

The correct design of the heating circuit to best match the operation of a heat pump

will result in a sucessful and efficient installation.

 

 

 

The efficiency of a heat pump is measured as the ratio of energy or heat out to the

electrical energy used. This efficiency ratio is called the coefficient of performance.

It varies with the air or ground source temperature and also with the temperature

of the water delivered to the heating system.

Ground source heat pump extract solar energy stored in the ground. This can be done

with a closed loop of polyethylene pipe containing an antifreeze mixture buried either

horizontally or vertically. Alternatively ground water or water from a river or lake can be

used in a open loop system.

The design of the ground loop, both thermally and hydraulically, is critical to the succces

of a ground source heat pump installation.

 

 

A ground source heat pump is usually more efficient than a comparable air source unit as

the ground temperature is more stable and higher  than the air temperature during the

winter heating season. Howeve due to the installation of the ground loop it is usually

more expensive to install initially.