Balboa Heater On All Of The Time

[demolady]

I have a no-name brand spa the uses Balboa controls. It is an older M7 with a pleasure switch on the heater assembly. It heats all of the time.

Here are the symptoms of the problem: starting with a tub temp below the heater turn on point, turn on the power 220 VAC to the tub and the tub heats normally. I have the temp set at 100 degrees. When the tub temp indicates 101 for a bit, the heater light goes out and the pump continues to run. All is normal up to this point. But instead of the pump shutting off after it cools the heater, it continues to run and it continues to heat (with the heat light OFF). After a while the temp gets to about 107 degrees and OH error occurs as you would expect. The tub is now shut down. The only way to restore it is to power cycle the 220 VAC. It seems to me that the M7 controller is basically functional with the exception that the heater never really shuts off even though the controller tells it to (heat light OFF).

What I have done: The tub is about 5 years old so decided to do some maintenance while troubleshooting the problem. I have replaced the heater assembly (Over temp probe, heater element and pleasure switch) and the Temp probe into the tub. I have rebuilt the heater pump. I am running it without any filters to eliminate flow as a problem.

Are there any relays on the M7 controller that could be welded shut? Other solid state switchs that could be shorted? Do you have any suggestions? My next step will be to replace the controller board.

Thanks ahead of time for your assistance.

[ps558]

I have a no-name brand spa the uses Balboa controls. It is an older M7 with a pleasure switch on the heater assembly. It heats all of the time.

Here are the symptoms of the problem: starting with a tub temp below the heater turn on point, turn on the power 220 VAC to the tub and the tub heats normally. I have the temp set at 100 degrees. When the tub temp indicates 101 for a bit, the heater light goes out and the pump continues to run. All is normal up to this point. But instead of the pump shutting off after it cools the heater, it continues to run and it continues to heat (with the heat light OFF). After a while the temp gets to about 107 degrees and OH error occurs as you would expect. The tub is now shut down. The only way to restore it is to power cycle the 220 VAC. It seems to me that the M7 controller is basically functional with the exception that the heater never really shuts off even though the controller tells it to (heat light OFF).

What I have done: The tub is about 5 years old so decided to do some maintenance while troubleshooting the problem. I have replaced the heater assembly (Over temp probe, heater element and pleasure switch) and the Temp probe into the tub. I have rebuilt the heater pump. I am running it without any filters to eliminate flow as a problem.

Are there any relays on the M7 controller that could be welded shut? Other solid state switchs that could be shorted? Do you have any suggestions? My next step will be to replace the controller board.

Thanks ahead of time for your assistance.

Check the filter cycle it might be on continous were the pump will never shut off and which will keep rising the temp in the spa.

[ALASKA RECREATIONAL]

Phone BALBOA in California and for $125.00 they will replace your curcirt board with a new one. What you have is the relay that turns on and off the heater is stuck in the on/closed position. Look up BalBoa Insturment on the web and call them this Monday. The relays (2) that opens when you have a overheat, are located to the left & above the heater relay. (lower left corner of the board.) the M7 board marks their relays.

So from the lower left of your board the first relay is the (K4) "Hi Limit" relay Next to it is the heater relay (this is the one your having problems with) and above the heater relay is the other (K3) "Hi Limit" relay.

This relay is made by : ZETTLER #AZ2120-1A-15DF (IF ITS A OPEN FACE RELAY, NO COVER) If its got a cover on the relay then its a (ZELLLAR #AZ2160-1A-15DEF) I repair these all the time and the relay is not that hard to change. GOOD LUCK. Don't try to change this relay if your not good a soldiering cause most of the time people just screw up the board. keep us informed.

[edbianc]

I know this is an old post but it was very helpful to me and I thought posting a picture of the suspect relay may help others. I was able to get the relay to work again by manually moving the contacts back and forth a few times (with the power off). I assume the contacts were either dirty or partially welded together. I also ordered the referenced relay mentioned in this post from Amazon for $7.50 as a backup if it fails again. Here is a picture of the heater relay indicated by the arrow:

https://files.acrobat.com/a/preview/7dae21b5-bf28-432a-afcf-7d6a11f3fa98