Pumps, filters and equipment
A pool heat pump that is not heating
A heat pump moves heat from the air into the water. If either the air or the water is not flowing properly, it cannot do its job.
Pool heat pumps take heat from the surrounding air and pass it into the water through a heat exchanger. In the cooler Dubai months, when owners most want warmer water, they can work well — but they depend on enough water flowing through the exchanger, free airflow across the coil and fan, and a controller set to heat.
Equipment guides cover servicing and faults on the plant an existing pool already has.
The commonest faults are not inside the refrigeration circuit. A dirty filter or misset valve can reduce flow enough for the flow switch to stop the unit. Dust, leaves or items stored around the unit restrict the airflow. The controller may be in the wrong mode after a power cut. Only when those are ruled out does diagnosis move to refrigerant, sensors and electrical parts, which need a qualified technician.
The short version
Water flow through the unit
Low flow trips the flow switch or reduces heating sharply.
Air across the coil
Dust and obstructions cut the heat the unit can collect.
Controller settings
Mode and set temperature can change after a power cut.
What a technician checks
Flow and the filter
Filter pressure, valve positions, bypass settings and the flow switch.
Coil and fan
Cleaning the evaporator coil, checking the fan and clearing space around the unit.
Diagnostics
Fault codes, sensors, electrical supply and, where indicated, the refrigerant circuit.
Before calling
Check mode and set temperature
Confirm it is set to heat and the target is above the water temperature.
Note any fault code
A photo of the display saves time.
Clear around the unit
Make sure nothing is blocking the fan or coil.
Common questions
Why does the pool heat so slowly?
Heat pumps raise water temperature gradually, more slowly in cooler air and faster with a cover on.
Can a heat pump also cool the pool?
Some models can reverse to cool, depending on their design.
Does a pool cover help?
Yes. Most heat is lost from the surface, so a cover helps the unit keep up.
Related pool care guides
- A pool chiller that is not cooling enoughA related check on the same part of the plant.
- Servicing a pool heat pump or chillerA related check on the same part of the plant.
- Repairing or replacing a pool pumpA related choice about how the pool is looked after.
- When pool pH is too highAnother water problem with a related cause.
This guide sits under pool equipment repair. Browse all pool care guides. We look after pools at homes and commercial properties across Dubai.
Ask about your pool
Tell us where the pool is and what you are seeing. A photograph of the pool and the plant room helps us plan the visit.
Phone
+971 56 181 0106Talk through what the pool is doing and book a time for us to see it.
WhatsApp
Send a messageThe easiest way to send photographs of the pool and plant room.
Next step
Heat pump not warming the pool?
Send the model, a photo of the display and your filter pressure. We will arrange a check.