Hydro Spa Endurance - Flo Message

[virvis]

Hydro Spa Endurance - Water change a few weeks ago and have issues ever since. drained and refilled tub. Started it back up and got FLO message. Removed filter and tried to restart to no avail. After researching, thought is may be an air lock. Have cracked all fitting around heater but still have FLO message on startup. If I turn jets on as soon as I power the spa back up, it will run and heat up to the desired temp. and kick off as normal but when temp. drops a few degrees and spa tries to fire heater again, FLO message will appear and will not heat and jets will not come on even if I hit the button. If I power it off and back on, hit jets button again, it will repeat the above process.

Any suggestions?

I have photos of the inside plumbing and electrical systems but I'm new here and haven't figured out how to post photos yet.

[Roger]

Find the flow sensor just past the heater on the return line to the tubs plumbing. Check to see that the contacts are clean and functioning properly.

[virvis]

Thanks for the reply Roger. I believe they are working properly. If I take them off and use a jumper wire, the heater will come on but the pump does not.

When it is connected, it prevents the heater from engaging because the main pump is not running.

[Roger]

Has to be the board then