Post by Admin on Jul 25, 2022 17:36:40 GMT -2
The AWHP sizing process is to match the heat load of the home to the heat loss. While this is an unwritten rule it is not written in stone either, to cover 100% of the heat loss. If the load cannot be met, the balance would be made up by auxiliary heat from either electric, gas or oil appliances.
All AWHP's will operate outside the normal delta-T in North America of 20f for the heating system. It is common to operate the AWHP delta-T to <5f or less.
While AWHP's can be operated in most heating systems it would be advised for homes of less than 10-20 btu's per sq ft. The design of the system should work as low of water temperature as possible.
Dependent on the ratio of radiation to heat loss, determine the lowest water temperature required to heat the home. This will maximize the COP of the heat pump.
The bottom line is if you are going to install an AWHP do proper heat loss, oversize the AWHP slightly, pay special attention to circulator and pipe sizes due to a Delta-T of 5F. If done properly the operating cost should be less than oil or gas operating boilers.
All AWHP's will operate outside the normal delta-T in North America of 20f for the heating system. It is common to operate the AWHP delta-T to <5f or less.
While AWHP's can be operated in most heating systems it would be advised for homes of less than 10-20 btu's per sq ft. The design of the system should work as low of water temperature as possible.
Dependent on the ratio of radiation to heat loss, determine the lowest water temperature required to heat the home. This will maximize the COP of the heat pump.
The bottom line is if you are going to install an AWHP do proper heat loss, oversize the AWHP slightly, pay special attention to circulator and pipe sizes due to a Delta-T of 5F. If done properly the operating cost should be less than oil or gas operating boilers.