Why Is My Pool Heater Not Turning On? Common Causes
By the BlueIQ Pools team ·
A pool heater that will not fire is one of the most common service calls we get. Here are the usual causes, from simplest to most involved.
1. The heater is not being called for heat
Check the set temperature and mode. On automated pools, the heater may be off in the schedule, set to the wrong body of water (pool vs. spa), or waiting for the pump to run.
2. Low water flow
A dirty filter, clogged baskets or a pump running too slowly can keep the pressure switch from closing. Heaters are designed not to fire without enough flow.
3. Pressure or flow switch problems
A failed or misadjusted switch can block the heater even when flow is fine.
4. Ignition problems (gas heaters)
A dirty flame sensor, failed igniter or gas supply issue will show up as an ignition error.
5. Heat pump conditions
Heat pumps may not run when air temperatures are low, or may fault due to airflow or refrigerant issues.
6. Control board or wiring
Failed boards, loose wiring and relay problems at the automation panel are common - and this is where electrical expertise matters.
When to call a pro
Basic checks like the filter and settings are safe for homeowners. Anything involving gas, high voltage or internal components should be handled by a professional.
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BlueIQ Pools serves all of New Jersey.