Cold-climate operation
The RV series is designed for heating operation in outdoor temperatures down to −20 °C, subject to operating conditions and system design. What changes on the way down matters as much as the limit itself.
Capacity and COP fall with temperature
As outdoor air gets colder, there is less heat to extract per cubic metre, and the compressor has to lift the temperature further. Two things happen at once: the maximum heating capacity falls, and so does the COP. Electrical input does not fall proportionally, so each kilowatt-hour of heat costs more electricity on a cold day than on a mild one. A higher water temperature makes both effects larger.
Why A7/W35 is not a sizing figure
The capacities on RV product pages are given at A7/W35: 7 °C outdoor and 35 °C water. That is a standard comparison point, not a winter condition. Sizing must use the capacity at the local design outdoor temperature and the design flow temperature, taken from the performance table for the model. We supply that table with every proposal.
Balance point and backup heat
The balance point is the outdoor temperature at which the heat pump's available capacity equals the building's heat loss. Below it, a backup heater or a second heat source covers the difference. A careful design keeps the balance point low so backup energy stays a small share of the season.
Cold-climate installation checklist
- Use the local design outdoor temperature, not the average winter temperature.
- Keep the flow temperature as low as the emitters allow; see weather compensation.
- Raise the unit above expected snow depth and give meltwater a clear drain path.
- Configure defrost support and anti-freeze protection.
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Talk to an engineer about your project
Send the building details, location and the emitters you plan to use. We come back with a model proposal and a quotation.