We bought and installed a new hottub (Pinnacle, Meridian model) http://www.premiumleisure.com/PinnacleSpas/Meridian.html, outside installation. We had an electrician wire it in from the house with a 2-leg GFCI in a box next to the tub. We finally got it running the week before Thanksgiving. It has a 2 speed jets pump, but we couldn't get it to come on high speed. I thought it was a bad pump, but when I put a meter on the black and red wires from the breaker box inside the Balboa Control box inside the tub, I found it was only getting 120v instead of 240. So I tested the breaker box and I had 240v coming into the box from the house, but only 120 on the other side of the breaker.

As it turns out, the GFCI breaker in the box had a bad leg so only 120-volts was going to the pump (and the heater, which now explains why it would lose temperature so quickly when we took the cover off).

Well, guess what, I'm on my thrid GFCI breaker. Each time I put one in, one leg burns out. Something, it seems to me, in the hottub is shorting out and burning up one leg of the breaker. However, it doesn't seem to be a dead short since it's not tripping the breaker, just burning one leg out.

Any ideas ? I can't afford to keep buying 2-leg GFCI breakers.....

TRY TESTING THE BREAKER IN YOUR HOUSE PANEL, sounds to me like you have a pair of single pole breakers trying to do what needs to be a double pole breaker. If you have a double pole (two breakers combined into one with a bar across both buttons) you should read 220 or 240 volts across both terminals or 1/2 of that reading from each lug to ground.
If you read 220+ across both lugs and it's a "double pole breaker" your problem lies elseware.
Good Luck, Howard
I'm new to these forums as of today.

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