Sherryf

Anyone out there that can help please?

My husband drained the spa and refilled it. Afterwards the heater return wasn’t putting out water. He had a service person out. Looks like he replaced the main circuit board. Now the heater return works great but it will not heat up. The jets are strong with no surging. On the control panel the power light is solid red and the ready light flashed green. On the circuit boards the D9 is flashing red and D10 is solid green. LIM is solid green. HTR ON lights up green for a few seconds then goes off. The pressure switch looks like it has already been shorted out to itself. When the jets are on D17 is solid red. We have been waiting for the service person for months. I would love to fix this ourselves and cancel our service call. Thanks for any help.