Hot tub heater parts
Hot tub heater parts
Heaters, pressure and flow switches, sensors and heater plumbing, matched to your control system, voltage and wattage. Here's what each part does and the signs that point to it.
Before you order: rule out the simple stuff
Most "bad heater" calls are really flow problems. Check these first:
- The spa has power: GFCI and breaker on, topside lit.
- Water is above the skimmer, the filter is clean (try running briefly without it, power off to remove it), and valves and jets are open.
- Any code on the topside is written down exactly.
- After a refill, the pumps are primed (no airlock).
Our guides hot tub not heating, weak jets and airlock after a refill walk through the safe checks.
Which part? Common symptoms
The same symptom can have more than one cause, so a tech confirms it before you buy.
| What you're seeing | Parts often involved |
|---|---|
| Flow code (FLO, HFL, LF) with good water level and a clean filter | Pressure or flow switch, airlock, circulation or jet pump |
| Runs, no heat, no code | Heater element, heater relay on the control pack, settings |
| GFCI trips when the heater comes on | Heater element (needs testing first; see GFCI keeps tripping) |
| Sensor or overheat message | Temperature or high-limit sensor (see Balboa / Gecko codes) |
| Drip at the heater | Heater unions, gaskets or o-rings |
Heater parts we source
Heater assemblies & elements
Complete heater assemblies (manifolds) and replacement elements, matched to your control system, wattage and voltage.
Common sign: Spa runs but won't heat after flow, filter and settings are checked, or trips the GFCI when heating.
Pressure & flow switches
The switch that proves water is flowing before the heater is allowed on. Matched to your heater and control.
Common sign: Flow codes (FLO, HFL, LF) with a clean filter and good water level.
Temperature & high-limit sensors
Temperature and high-limit sensors and probes for Balboa, Gecko and other controls.
Common sign: Sensor or overheat messages, or a topside that disagrees with a thermometer.
Heater unions, gaskets & o-rings
Heater unions, tailpieces, gaskets and o-rings sized for your heater and plumbing.
Common sign: Drips or leaks at the heater connections.
Why the exact part matters
Spa heaters differ by control brand, length, wattage, voltage, sensor ports and how they connect to the pack. Many are built for one control family. That's why we ask for the control pack label and the old heater's label, instead of guessing from a photo.
Where to find the model and part numbers
- The spa's model and serial label is usually inside the equipment bay, on the cabinet frame or the control pack, or on the skirt. Your owner's manual or receipt also lists the model.
- Pumps, heaters and control packs each have their own label with a part number, voltage and horsepower or wattage. Photograph those too.
- Turn the spa off at its GFCI or breaker before you open the equipment bay to look.
- Topside panels often have a part number on the back. If it's still mounted, a photo of the front is fine.
Brands we source and help find heater parts for
- Balboa
- Gecko
- Hydro-Quip
- Jacuzzi
- Sundance Spas
- Hot Spring
- Caldera
- Master Spas
- Cal Spas
- Bullfrog
- Marquis
Common questions
Will any hot tub heater fit my spa?
No. Heaters are made for specific control systems, voltages and wattages, and the length and connections matter. Send us your control pack label and the old heater's label and we'll match the right one.
Is it the heater or the pressure switch?
If you get a flow code with good water flow, the pressure or flow switch is a common suspect. If there's no code and no heat, the element or heater relay is more likely. A tech can tell on a short video call before you buy anything.
Can I return a hot tub heater?
Heaters are electrical parts, and electrical parts and special orders can't be returned once ordered. That's exactly why a tech confirms the right heater with you before you pay.
Related guides
Hot tub not heating
Jets run but the water stays cold. Usually it's flow, not the heater.
Read the guideGFCI keeps tripping
The spa shuts off and the GFCI won't stay on. Treat it as a safety signal.
Read the guideBalboa error codes
HFL, LF, dr, OHH, OHS, sensor and GFCI messages, from Balboa's own guides.
Read the guideGecko error codes
FLO, HL, OH, Prr, AOH and UPL, from Gecko's troubleshooting guide.
Read the guideSources
- Balboa Water Group, TP500S / TP600 system user guide (42339 rev A1): priming mode, freeze protection, GFCI trip test and message codes
- Gecko Alliance, Y-series and in.xe troubleshooting guide (9919-101313-D, rev. July 2023): FLO, HL, OH, Prr, AOH and UPL messages
- Hot Spring Spas (Watkins Wellness), Hot Spot collection SX/TX owner's manual: GFCI and high-limit checks, priming, drain & refill, winterizing and troubleshooting tables
Brand names are trademarks of their owners. We're an independent parts and support service, not affiliated with, endorsed by or an authorized dealer for any manufacturer. These are brands we source and help find parts for. Availability depends on the part and model, and your quote confirms it.
← All hot tub parts · Pumps · Control packs & topsides · Filters · Covers & lifters · Troubleshooting guides