Calspa Heater Boils After Pump Shutoff

[puttalong]

well guys, this is really the first problem ive had out of this 2003 calspa. its a very basic model with only pump on/off controls, and a temp control. I hate to just start throwing parts at a problem hoping to fix it, that gets expensive. after searching through SEVERAL heater topics, it seems I have an uncommon issue:

the spa will work perfectly when heating up to set temp, at which point the pump shuts off, and the heater starts to boil the water inside it. this eventually activates the OH error code, effectively shutting down the heater and the boiling stops. I have drained the tub and refilled it, hoping I had some sort of vapor lock issue. the same problem resurfaces regardless of filter presence. the power from the jets seems strong as ever. I can reset the OH after about 30 minutes and the spa will work until the pump shuts off, or, if it is already at operating temp or set below operating temp, the heater comes on without the pump, boils the water, and shuts down again with OH error code.

suggestions welcome, TIA

puttalong

[Spa Board Doctor]

You have a stuck heater relay on the PC board. This is a common issue and is repairable. It is also possible that after the many overheat occurrences the high limit probe may have been compromised and should be replaced as well.

BB

[puttalong]

well that's good news that I shouldn't have to replace the mainboard. is that something I should ship off to have done? It has overheated probably 10 times while I was testing to isolate the problem, ill start looking for a hi limit sensor.

[puttalong]

got the combo hi limit/temp sensor, and am about to remove the circuit board to have the relays replaced.

[puttalong]

well, after seeing the same relays from spa dealers at around $30 each, i ended up ordering directly from the company that makes them for less than $2 each.....

[puttalong]

update:

spokanespas, thanks very much for the correct advice. from my initial shopping, I figured I was going to spend around $250 for a refurb replacement circuit board, or around $200 to refurb my own circuit board. after shopping for heat relays, I figured around $32 for each relay(from spa dealers), but which I found the exact replacements from an electronics dealer for $1.77 each. after buying 6 relays total, and finding a local circuit board repairman, he wouldn't even let me pay him for the 10 minutes it took him to replace the relays. Im guessing I saved at least a couple to more likely few hundred dollars by coming to this forum.

The spa is now running perfectly now, except for one jet, which will be replaced shortly.

me =

[Spa Board Doctor]

Thanks for the update! I'm glad you are tubbing again. I do this type of repair for people all over the country and the cost before freight is $92.00 - still a whole lot better than a new board.

- BB