August 9, 2023, 3:21 pm | Read time: 3 minutes
Are you wondering if a heat pump is possible in your home? There’s a simple test that offers initial guidance without needing a contractor or energy consultation.
A heat pump is not the best heating option for every older building. For example, in buildings with small radiators, extensive renovations may be necessary when replacing the heating system. You can determine if this is a concern for your home with a simple test—before consulting a contractor or energy advisor.
Test Shows if a Heat Pump Is Worthwhile
It’s important to conduct this test during the heating season. On a cold winter day, limit the heating system’s flow temperature to 55 degrees, and set all radiator thermostats to level 3. On a thermostat with precise temperature settings, this corresponds to about 68 degrees Fahrenheit. Peter Kafke from the consumer advice center’s energy consultation explains the results:
- If all rooms become warm, installing a heat pump should be no problem.
- If some rooms remain cold, replacing the radiators with larger ones may suffice.
- If all rooms stay too cool, a heat pump will only work economically if the building envelope is additionally insulated.
Related: Types of Heat Pumps and How They Work
However, such a test on your own system can only provide initial guidance. Heat pump manufacturers are increasingly offering systems that can work efficiently in older buildings requiring higher flow temperatures. Therefore, even with a poor test result, it may be worthwhile to consult an energy advisor or heating contractor familiar with the latest developments.
Is a Heat Pump Problematic in Older Buildings?
In energy-efficient new buildings, heat pumps have been the leading heating system for years, but in older buildings, there have long been obstacles to this type of heating. Heat pumps typically only worked efficiently in systems with a low flow temperature. This is the temperature the heating water needs when it flows into the pipes and radiators. Many systems only worked efficiently with flow temperatures up to 55 degrees Celsius (131 degrees Fahrenheit). This was feasible in buildings with underfloor heating, which have large areas that radiate heat.
More on this: Is a Heat Pump Worth It for My House?
If radiators are not large enough and the building is not sufficiently insulated, higher temperatures are needed. Conventional heat pumps only achieved these with more electricity—and thus higher operating costs.
But there are technical developments in heat pumps: Every reputable manufacturer now offers devices specifically for older buildings that efficiently achieve flow temperatures of 65 to 75 degrees Celsius (149 to 167 degrees Fahrenheit), or have announced such developments at trade fairs. So-called propane heat pumps, which use the natural refrigerant R290, are considered particularly energy-efficient.
with material from dpa