Quick answer: Check the set temperature, water flow, filter cleanliness, bypass, outdoor temperature, unit mode and any error messages.
When a pool heat pump does not heat, it is not necessarily faulty. Often it is the flow, a setting, low outdoor temperature, or expectations about heating speed.
Basic check
Start with things that do not require opening the unit. Only then does it make sense to deal with the refrigerant circuit or a service call.
- set target temperature
- heating mode
- filtration running
- sufficient flow
- clean filter
- correctly set bypass
Why heating takes longer
A large water volume, cold nights, wind and an uncovered pool significantly slow down heating. A cover often helps more than extra hours of operation.
- use a cover
- account for heat loss at night
- do not compare a small and a large pool
- track the actual rise over 24 hours
When it is time for a service
Call a service company for an error code, icing of the heat exchanger beyond normal defrosting, unusual noise, or if the unit does not switch on despite the conditions being met.
Related guides
This article is original editorial guidance by Spa Pool News. For chemicals, electrical equipment and service work, always follow the manufacturer’s instructions and safety recommendations.
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