6 Air to Water Heat Pump Installation Tips

The design and installation of air to water heat pump heating and cooling systems are demanding. A slight mistake might cause problems in the later operation period. For this reason, we consult engineers who have a lot of experiences in the design and installation of air source heat pumps, and share practical tips with you for your reference.

Use soft water in the system as much as possible.

Many people may not pay much attention to the water quality problem when installing the heating and cooling air to water heat pump system. In some areas, the proportion of calcium and magnesium ions in water is very high. When they increase in the system, they may cause blockage in the pipes, Y-type filters, water pump and so on, which seriously affects the performance of the heat pump. 

In addition, in areas where the temperature is relatively low in winter, a certain amount of antifreeze fluid or alcohol should be added. Antifreeze liquid usually has instructions. If alcohol is used, 99°industrial alcohol is recommended. The amount of alcohol can be adjusted according to the actual situation and the circulating water volume in the system. For example, the circulating water amount in the system is 100L, plus a kilogram of alcohol, the alcohol content of the water is basically 1%, and then the freezing temperature of the water is -1℃. In many areas, the temperature is low in winter. When users do not use floor heating or have power cut off at night for a long time, it is easy to cause pipelines or units to freeze and crack. Therefore, a certain amount of antifreeze liquid or alcohol is needed.

Fan coils must be equipped with two-way valves.

Because there is no two-way ball valve, you might feel cold air coming out in some rooms even when the system is not in use, and the electricity consumption of the system will be slightly higher. Therefore, a two-way ball valve should be installed at the water outlet of the fan coil, and if there are five or six fan coils in the whole system, at least one fan coil should be equipped with a three-way ball valve.

Why is it necessary to have a fan coil and a three-way ball valve in the system? If only two-way ball valves are used, when the user seldom uses fan coils but only opens one or two, the resistance of water in the system is very huge, which easily causes the vibration of the pipelines and then produces noise.

Use canned-motor water pumps or multistage centrifugal water pumps whenever possible.

It is very important to choose the right type of water pump for the heating and cooling system. Generally, a closed loop water pumping system is recommended. The pressure of each point in the closed loop system is equal, so there is no need to consider the drop of water pipe but only the main force of pipe bend and length. Thus, it is recommended to use a canned-motor pump or multistage centrifugal pump instead of a booster one.

All pipes must be insulated. 

Whether we are installing a heating and cooling system at home or doing a hot water project, the indoor pipes, especially the pipes inside the ceiling, must be insulated. For the heating and cooling two-way supply system, condensate drain pipes should be taped with insulated cotton to prevent condensate leaks.

Automatic exhaust valve should be installed at the top of the system.

In the case that the location of the water tank is not well determined, we should determine it according to the actual situation. It would be better if it can be installed at the top. But in some cases, the water tank can only be installed on the ground or somewhere lower, so the exhaust problem should be considered for the system. 

If the water tank is installed higher than the system pipelines, an automatic exhaust valve can be installed at the top of the water tank, since both the fan coil and floor heating units have their manual exhaust valves. If the position of the water tank is lower than that of the system pipes, an automatic exhaust valve must be installed at the top of the intake and return water pipeline of the system in addition to the water tank.

Main system pipelines must be straight.

The main pipes of the whole system must be straight and slight uphill along the flow direction is the best. That is to say, the inlet pipe should be slightly raised while the return pipe should be slightly lowered, so as to facilitate the discharge of air in the pipelines. The main pipes must not be U-shaped, which will cause air blockage, and timely use of soft connections is neither feasible.