The heater clicks but never lights
Pool Heater Repair
Pool heater not firing, heating slowly, or shutting off?
A heater problem is not always a full replacement. Avalon Pools checks the obvious failure points first, explains what is wrong, and gives practical repair or replacement options.
Symptoms
What homeowners usually notice
The spa heats slowly or stops before reaching temperature
The display shows an error code
The heater starts, runs briefly, then shuts down
The equipment pad smells like gas or sounds different than normal
Common causes
- Dirty filters or weak water flow triggering safety shutdowns
- Ignition, sensor, pressure switch, or control board issues
- Gas supply, valve, or venting problems
- Old heater components that are no longer worth chasing one part at a time
What Avalon checks
- Water flow, filter pressure, valves, and bypass position
- Heater startup sequence, display codes, and shutdown behavior
- Visible corrosion, leaks, wiring condition, and equipment pad layout
- Whether repair, replacement, or a related pump/filter fix makes the most sense
Repair or replace?
- Repair often makes sense when the heater is newer and the issue is isolated.
- Replacement is usually cleaner when the heater is old, corroded, unreliable, or stacking multiple part failures.
- If poor flow is causing the heater issue, the right fix may start with the pump, filter, or valves.
Repair Help
Need a pool heater checked?
Call Avalon Pools for heater troubleshooting, repair guidance, or replacement options across the core San Gabriel Valley route.
FAQ
Practical answers before the first visit
Why does my pool heater turn on and then shut off?
Common causes include low water flow, dirty filters, pressure switch issues, sensor faults, or ignition problems. The first step is checking the flow and shutdown behavior before replacing parts.
Is it worth repairing an old pool heater?
Sometimes. If the heater is structurally sound and the issue is isolated, repair can make sense. If it is corroded, unreliable, or has multiple failing parts, replacement may be the better value.
Related Pages
Related repair, service, and local pages
Continue from this guide into the service page, nearby guides, or Avalon Pools route cities.
Pool Equipment RepairPump, heater, filter, valve, salt system, and circulation troubleshooting.Equipment Upgrades & New InstallsNew pumps, heaters, filters, salt systems, automation, and cleaner equipment pads.Pool Filter Cleaning GuideHow dirty filters affect pressure, flow, cloudy water, pumps, and heaters.Pool Pump Repair GuideCommon causes of noisy pumps, leaks, low flow, and priming problems.ArcadiaPriority weekly pool service, equipment repair, and install work in Arcadia.MonroviaCore route pool service, green pool cleanup, repairs, and equipment installs.GlendoraWeekly pool care, heater installs, pump work, and equipment troubleshooting.Sierra MadrePool service for foothill debris, filtration, weekly care, and equipment repair.PasadenaWeekly service, filter cleaning, pump replacement, heater help, and automation.
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Quality pool maintenance and equipment service for homeowners who want consistency, clear answers, and clean water.