Berlin//Sankt Augustin (dpa/tmn) – Continuous rain, storms, hail, thunderstorms: mandatory components of heat pumps that are mounted outside the house are exposed to wind and weather.
Heat pumps are designed for outdoor use and can withstand normal to heavy rain and snowfall. Even rough winds can't do much damage to them. However, the situation is different when it comes to floods or lightning strikes. These can damage the heat pump's electrical system and motor.
“Heat pumps are no more at risk in extreme weather events than, for example, oil or pellet heating,” says Katja Weinhold, press spokesperson for the German Heat Pump Association in Berlin. “But there are a few things that should be taken into account before installation and during operation so that the outdoor units of air-water heat pumps in particular can survive flooding or strong gusts of wind unscathed.”
The heat pump's outdoor unit, which draws heat from the ground, groundwater or air depending on the type, needs a secure location and a firm anchoring. It is usually mounted on a base near the house's facade. The indoor unit, which feeds the heat into the house's heating system, is often located in the basement. It is usually safe here, but could be damaged in the event of flooding.
Height matters
“The heat pump is an electrical device, like a boiler,” says Matthias Wagnitz from the Central Association for Sanitation, Heating and Air Conditioning in Sankt Augustin. “As soon as the boiler is under water, it often needs to be replaced. The same applies to the heat pump.”
To avoid this, heat pumps should be installed in front of the house at a height where they are protected from rising water in the event of heavy rain or flooding. Katja Weinhold recommends higher foundations for outdoors in flood areas: “Normally, heat pumps should be about 50 centimeters above the ground, but higher in flood areas.”
In particularly vulnerable locations, the heat pump's outdoor unit can even be placed on a roof, depending on the type. This could include on a garage roof or on an extension – provided that the technical requirements can be met, for example with regard to noise emissions, and a connection to the indoor unit is possible.
Incidentally, in the basement, it should not be placed directly on the floor if possible. “Indoor units are safe from flooding in the basement if they are placed high enough and the waste water drains are properly secured below the flood level,” says Wagnitz.
Switch off heat pump if there is a risk of flooding
And what can you do if heavy rain is forecast? “It is important to switch off the heat pump if there is a risk of flooding,” says Katja Weinhold. It is not powered the entire time, but only switches on for heating. But it is safer to switch it off completely if there is a risk.
Heat pumps are – as is usually the case with all heating systems – connected to water-based heating systems and hot water pipes. Therefore, after switching off, the heating circuit should also be shut off and the shut-off valves should be closed as a precaution in case the radiator is torn off.
If water does get into the heat pump, it is not necessarily broken. “If the electrical system is intact, it will dry out and can be put back into operation later,” says Katja Weinhold. The mechanics are also not so sensitive that they fail quickly. “However, if the device has been full of water, it is better to have a specialist look at it before it is switched on again,” she advises.
Insurance cover for the heat pump
But water is not the only danger for the outdoor devices; storms and hail can also cause problems. They are usually mounted so firmly that even strong gusts of wind cannot tear them from their anchorage. Hailstones can only damage the casing, but not the internal components. “But falling trees can cause major damage if they land on them,” says Matthias Wagnitz. Lightning can damage the electronics.
However, it is unlikely that lightning will strike the device directly, as it is usually located close to the ground. However, a nearby strike can lead to an overvoltage in the power grid, which damages the heat pump's electronics. A surge protector in the house prevents this.
A heat pump can usually be insured through the building insurance of the house. “Anyone who buys a new device should ask their insurance company whether it is included in the insurance,” says Katja Weinhold. This is not always automatically the case.
© dpa-infocom, dpa:240901-930-220108/1
