Sundance Hamilton heater not raising temp to setting

[Ann Popplestone]

I have a ten- year old Hamilton that is not heating correctly. The heater light on the control panel is on, but the water temperature will not go above 93, about 20 deg above air temp.  I have replaced the filters, flow valve, and temperature sensor. The sn1 error that I had initially has gone,  it I am still getting a flo1 error even though I can see the valve opening and closing. Is it the heater? The thermostat? Evil spirits?

[ratchett]

Have you tested the flow sensor with a multimeter to confirm you're getting correct readings?  What about the temperature sensors - have you tested them to confirm they're reading?

 

Does the control board have LED lights to indicate when it's calling for heat?  Is the board calling for heat or not?

 

On 7/23/2022 at 10:46 PM, Ann Popplestone said:

I am still getting a flo1 error even though I can see the valve opening and closing.

I'm far from an expert, but if there is a flow sensor error, that would indicate the hot tub thinks that the heater is dry, so it's not going to even try sending power to the heater and risk damage. Until the flow error is cleared, the system will never kick on the heater.

I know you said you replaced the flow sensor, but are you positive it's working correctly?  Might be worth using a multimeter to confirm it's getting a reading when closed.