hot tub turning off itself

[spacko]

Hi i have a hydropool serenity hot tub. it is one with a circuit board. it has been working fine for the 8month i have had it. i had not been in it for a week so decided to go in. opened up and found no power  and it was cold. it has not tripped the main fuse in the fuse board. i have a safety switch on the wall next to the tub. i turned that off and on and it started up. after about 30mins it turned itself off. i have searched a few sites. i first thought it could be the high limit switch. but it seems i don't have one with a circuit board. i took the filter out even though it is not that old as read that could be the cause no luck. also opened the pipes to the pump to realise air. but none came out. through trying the tub several times. as needed to check it after each of my attempts. i can say that it stay on usually between 20 mins and an hour before cutting off. it does not try to start again by itself i have to turn off at the wall and back on. i also have no codes on the digital display.


Any thoughts would be much appreciated.

Many Thanks Dan

[Jacuzzi Jim]

 If the tub is only 8 months old call your dealer.    Could be a couple things, most likely a bad circuit board.  As far as a high limit pretty sure you have one, I would be surprised if it didn't.  Doubt thats the problem though.

[wmccall]

My degree is in Electronics and I have very little experience with hot tub repair.  That said, can you run the tub for a couple of hours with the side panel off that gives you access to the electronics?  My thought is that if its overheating and shutting (the electronics, not the water) then it running ok for a few hours maybe a sign that this is the case.  If you can say that this is the case you might be able to further narrowing it down by hitting certain areas of the electronics with a hair dryer to see what shuts it down.  FWIW

[spacko]

the tub is older than that but i acquired it 8 months ago. so is out of warranty. it also does not overheat more it does not heat at all. it will stay powered on sleep mode ( circulating water but not applying heat ) as soon as i turn the heat up it cuts out. but no trip. i fear it is not the sensors as i believe they would report a digital code rather than shut the tub down . the heater i feel would not shut it down either not heat it or trip it. and the element again i feel would trip if it was bad.  could it be the board? or i have heard things about checking the transformer. thanks for your replies