At present, as the temperature drops, ensuring heating in the house has become a top priority. For heat pumps, here are 7 measures protect heat pump from freeze in winter
1. Sure the thermal insulation effect of the pipeline
It is very important to keep the pipes warm, the exposed water pipes will cool down when the external ambient temperature decreases. Those who have not kept the pipeline warm before should put on “clothes” for the pipeline as soon as possible. After wearing up, the water pipe will be warm, and the water temperature in the pipeline will not drop too much or too quick.
For outdoor the air source heat pump pipe insulation adopts B1 grade 30mm thick material, for indoor it can use American B1 grade 20mm thick material. (Black). The outdoor thermal insulation outer layer is made of aluminum skin, and the indoor thermal insulation outer layer is bound with white cable ties. Pipeline valves and bends must be well insulated so that no exposed points of the pipeline appear.
2. Do not power off the unit
The air source heat pump water system uses water as an intermediate medium for heat transfer. Normally, the equipment has anti-freeze function. When the water temperature drops to a certain temperature, the equipment will automatically start to prevent the equipment and pipelines from freezing.
If the weather temperature is relatively low, once we turn off the air source heat pump when we go out, it may cause the water temperature in the pipeline to drop sharply. If the temperature is too low, it may freeze the equipment and cause the equipment to malfunction. Therefore, when the heat pump unit does not run for a long time, such as: frequent power failure, shutdown of the unit at night, winter vacation, and infrequent use of the unit in winter, all water in the unit, water pump and outdoor pipeline should be drained to prevent the unit from freezing..
3. Condensing water should be properly handled
The air source heat pump will discharge a large amount of condensed water in the heating process. If there is a slight negligence in the discharge of the condensed water, the condensed water will be discharged through the pipes and will flow to the ground. If the temperature below zero, the condensed water will easily freeze into ice, which may freeze the drain pipe and then flow along the drainpipe. The pipe climbs up and eventually causes the equipment to fail to operate normally, so the condensed water should be cleaned regularly.
Therefore, the piping position of the condensed water must be properly designed.
First, the installation position of the heat pump unit can be raised higher. Under normal circumstances, the height of the heat pump from the ground should be no less than 30 cm. For areas with severe ice and snow, it is recommended to be at least 50 cm. Second, add heat tracing on the chassis of the heat pump to defrost frost and ice; third , Wrap the heating cable on the outer wall of the condensate water or defrost water drainage pipe to prevent freezing. This is the 3/7 protect measures for protect heat pump from freeze up in winter.
4. Install 3-way valve at the water inlet and outlet, and install the emptying valve
During installation, the drain valve and drain pipe should be installed at the lowest point of the water system. Even if it is not at the lowest position of the unit, the inlet and outlet of the unit should also be equipped with a drain valve. When the power outage is more than two hours or it needs to be shut down for a long time, such as when the unit is not used frequently for a long time, open the drain valve of the water inlet and outlet to drain the rainwater in the water pump of the main engine to prevent freezing and cracking after the temperature drops. Cut off the power. Then, perform a comprehensive inspection of the air source heat pump system before running it to ensure that there is no fault.
5. Add ethanol alcohol to the system water solution
Add more than 90% or more than 95% ethanol alcohol to increase frost resistance. The amount to be added depends on the local minimum temperature. For example, adding 1 kg of alcohol to 100 liters of water, its antifreeze index is -1 °C, and adding 5 kg of alcohol is -5 °C. When ethanol is added to the system for antifreeze, it should be noted that the amount should not exceed 40% of the total system water.
In addition, ethanol also has a defect, which is highly volatile. When the exhaust valve is installed in a relatively closed space, it is easy to cause the ethanol content in the space to exceed the standard. If it encounters an open flame, it may cause a fire. And because ethanol is highly volatile, it needs to be added after one or two years of use to maintain the original antifreeze performance.
6. Add antifreeze to the system
For example, antifreeze at -15°C and -25°C will increase the initial investment cost due to the high price of antifreeze. When using antifreeze, we must pay attention not to use cheap antifreeze, such as methanol-blended antifreeze, which is corrosive to pipelines and will cause great damage to valves, pipe fittings, water pumps, and unit heat exchangers.
7. Clean up debris and snow around the heat pump in time
If the ventilation of the installation location of the heat pump is not good, it will affect the heating effect of the heat pump. Therefore, it is necessary to clean up more. It should also be noted that the fan of the main engine blows cold air. This will lead to insufficient heat in the air, affecting the heating effect. If the snow is too heavy, the snow must be removed in time.
The above are the 7 protect measures for protect heat pump from freeze up in winter, hope it is helpful to you.