hot tub overheats

[ghougasian]

I bought a Marquis Spa for $500 that kept tripping the GFI breaker.  I found that the ozonator (which wasn't working) was causing the problem.  The tub doesn't trip the breaker anymore but now the heater won't turn off.When I turn the tub on, the temperature rises until the over-temp limit is reached and the unit shuts down.  As this is the first hot tub I have owned, I am not familiar with typical hot tub operations.  Is it normal for the pump to run 24/7 or is it supposed to cycle on and off?  Also, the pump seems to be running at a higher speed than necessary just to maintain the temperature.  

[HotTubMan]

Sounds like an issue with the thermostat or the thermal probe. I am not overly familiar with Marquis. Let us know what year it was built and someone here should be able to help you trouble shot further.

[Chas]

Your pump has two speeds. The spa should heat on the low speed. If you are running the jets continually, with the pump on high speed, then it is normal for the tub to overheat.

You need to find a setting where the jet pump runs on low speed, controlled by the setting of the thermostat. There may be a time delay: turn the jets off, set the thermostat for 102, and wait for ten minutes.

Stuart will be along shortly, so find out the year and model of tub you have so he doesn't have to ask...

[ghougasian]

The model number is DR-22-1-084070
I couldn't find a year.  Where can I find that?

[stuart]

The model number is DR-22-1-084070
I couldn't find a year.  Where can I find that?

OK, I missed this one....

According to my buddy at Marquis that is a 1994 Reward built in August of '94!

As far as the heat issue I have some questions, does the heat light stay on the whole time? is the motor running on high speed or low speed? Do you know what temp it is getting to before it shuts down?

You might have either a heat relay sticking or your pump is running on high speed and overheating the system...

[spatexport]

What is the temperature of the water in the tub when the heater shuts down?

Is there a timer to set the pump run time?

[Gary]

OK, I missed this one....

According to my buddy at Marquis that is a 1994 Reward built in August of '94!

As far as the heat issue I have some questions, does the heat light stay on the whole time? is the motor running on high speed or low speed? Do you know what temp it is getting to before it shuts down?

You might have either a heat relay sticking or your pump is running on high speed and overheating the system...

I with Stuart on this one. That is pretty much what I was thinking.

But to take it a step further. When the heat light turns off you will need to see if you lost voltage to the heater. If so it may the pump running on high, if not bad board (relay).