Balboa RS101 - no power to 1 of the heater circuits

[Dave Oneill]

Hi,

I just replaced the heater power relay on a Balboa RS101 converted to 240V operation. I had 0V coming out of both lines before changing the relay, but now I only seem to have 120V coming out of the black power line and 0V out the red one. I have 120V coming in on both circuits but I'm running out of ideas on what else to check.

Without 240V the tub is stuck at 74F and isn't heating beyond that. Everything else is working except the second heater circuit.

Does anybody have any ideas of what I could try or what I've missed - I'd rather not buy an entire new motherboard for something simple.

[CanadianSpaTech]

Has it ever run as a 240V or did you just make the conversion from 120V?

Disconnect the heater from the board J9 at test for power off the board red to black... do you get 240V... Wait until heat indicator light is solid on the topside and not flickering

https://peoplelikeclearwater.com/wp-content/uploads/2017/01/CONTROL-SYSTEM-OVERVIEW-240V.pdf

[Dave Oneill]

It's always run 240V, I'm getting 120V at the black heater output and 0V at the red one - I checked and have 2x120V at the two inputs.

I'm beginning to think that one of the relays I used to replace the bad ones was bad too?

You wouldn't happen to know which of, I'm guessing, K2 or K3 powers which line? It's not clear from the schematic nor the circuit board - I suspect that it's K3 and that's the problem. Fortunately, I over ordered when I got the replacement power relays but it's not a trivial job to pull out the circuit board and remove/replace the relay again.

Before I did this I had 2 x 0V at both red and black at J9 - so I'm fairly sure it's the relay.

[cranbiz]

You might have a bad solder joint. Wouldn't hurt to check them and reflow them. The joint should be bright silver. If it's dull or hazy, reflow it.