Jacuzzi resetting but not tripping GFI

[bonovox]

Hello All,

I have a Jacuzzi J-345 that resets after about 40 minutes (2 cycles).  You see the 888, followed by 356, and then it's back.  The GFI does not trip.  This is all local to the hot tub itself. 

I replaced the circuit board, same problem.  I wanted to ask for thoughts on replacing the transformer (separate part in the control box)?

What's odd to me is that when it resets, you can turn all jets back on full and it'll keep running.  But, if you turn one set of jets on, as an example, and then turn the heater on, it resets immediately and you can replicate that over and over.  I'm thinking the heater is just drawing more power from a bad transformer.  I'm not sure how hot transformers get, but this one is very hot when I've done troubleshooting.  Also, when it's cold out and I've had the hot tub compartment open and the door off the control box, I can't replicate the problem likely because the transformer isn't getting hot enough. 

The transformer is cheap and easy to install so I thought that might be a good next step.  Any thoughts?

[Spa_Tech]

I have had other digital systems have similar symptoms. When a chip is not recieving the proper voltage, the board may be going to default- I think it would be a good idea to verify that you have proper voltage to the spa and then check for source and output voltage on the tranformer.

[clover]

The transformer has a 240 volt input from the circuit board and deals with "low voltage" supply to control panel & lights.  You can check the voltage to the red and black pins of the plug and then the other color coded wires for output of 10 to 14 volts.

Your symptoms indicate it is "rebooting"?  Number one suspect is the circuit board/e-prom, but you already did that.  Have you contacted your dealer, and how old is the sps?

[bonovox]

The Spa is a 2005 model.  I use the term rebooting, but I'm wondering if it just hits low voltage because of a faulty transformer and cuts out.  I ordered the transformer from my local jacuzzi dealer, still waiting for it to arrive.

The dealer also is the one that replaced the board.

[hotter25]

I hate these types of problems as they always seem a little dangerous to me.  It might be time to look for a new tub.  From the sounds of it, this has been an ongoing issue with this tub, especially if this is the third board.  Even thought 2005 wasn't that long ago, the technology has gotten a lot better.  I have had a hot tub for a long time, but I was recently looking for hot tubs indianapolis.  I was amazed at the options and overall features of the units.  It is much different than in 1999 when I bought my last tub.