Hi guys,
My buddy was given a "new to him" hot tub. The original and only owners said the heater stopped working. We opened the control box and the heater relay (A.Zettler AZ2280-1C-240A) and wires were burnt. Everything else inside looks ok. (see pic)

We replaced the relay with the exact same one, and replaced the heater element as well. Ran new wires, but still no heat. We get a "FLO" error. We looked in the manual, but there isn't much there to assist in troubleshooting this.

Any help would be greatly appreciated.
CalSpas System 3000
Energy Saver
240V

P.S. We ran the tub with 2 of the 3 pumps on for a couple hours and the tub went from 69 degrees to 85 degrees. Is there some type of low flow switch which is bad and keeping the heater off???

Hey Ncal-

I"ve got the identical spa, identical situation (just installed, 2nd owner) and identical problem... mostly. Just now turned it on and no heat. Opened panel back up and found the fried relay.

Same relay burned. Leads fried a bit different, but same deal.

I'd guess you broke out the heater when moving (which you've figured out) and when it went, it took a sensor with it, since there is a flow sensor built into the heater.

Were you getting the flo error before your replaced the relay and heater?

jsj

ps - where did you get your parts?

pps - just moved away from SF where I surfed for the last 24 years at ocean beach. talk about wierd similarities