You turn on the heater for the spa and nothing happens, or it fires for a minute and shuts off. Heaters have several safety switches that stop them running when something is wrong, so a heater that won't start is usually protecting itself.
The Usual Causes
- Not enough water flow. A dirty filter, a clogged basket or a failing pump won't push enough water through, and the heater shuts down to protect itself.
- Ignition failure. The igniter or flame sensor is worn or dirty and the burner can't light.
- Gas supply. A closed valve, low pressure or an empty propane tank.
- A failed sensor or switch. Heaters rely on pressure, temperature and limit switches, and any one of them can stop it.
- Controls. The automation system or thermostat isn't calling for heat.
- Corrosion, scale or pests. Rust, mineral build-up and nests inside the cabinet are common in heaters that sit unused for months.
What an Error Code Means
Most modern heaters show a code when they shut down. The code tells you which safety tripped, not why. A flow error, for example, can be the heater, the filter, the pump or a valve. Finding the real cause is what the repair visit is for.
Why This Isn't a DIY Repair
A pool heater combines natural gas or propane, high voltage and combustion. Bypassing a safety switch to get it running is how heaters get destroyed and people get hurt. Please don't open the cabinet or reset it over and over. If you smell gas, shut off the gas supply and call your gas company.
What We Do
We check water flow first, then ignition, gas pressure, sensors and controls, so we fix the cause and not only the symptom. If the heater is near the end of its life, we'll tell you what a repair buys you compared with a replacement, with a firm price for both.
Heater not firing?
Get it fixed before the first cold weekend. Call and we'll diagnose it.