Hot Tub not heating

[Dean093]

I have a 2004 Sundance Spa that I can not get to heat. Its been running 24hrs and still at 67degrees. The heat symbol is in the upper left on the display and the only error code is cool I have no reason why it wont run I have checked filter water level replaced heating element water flow sensor ect I am at a loss. Please help

[RDspaguy]

Are you in economy mode?

Do you have a multimeter and know how to use it?

[Dean093]

I am not in economy mode and yes I have a multimeter and know how to use it

[RDspaguy]

Check for voltage at the heater terminals. You may also have a thermo-disc in the heater terminal compartment. Check it as well. If you have no voltage and you have a heat indicator on the topside then you probably have a bad relay on the circuit board. An electronics repair shop can likely replace it fairly cheap, but you will have to remove the board. Let me know what you find.

Can you post a pic of the circuit board?

[Dean093]

I checked the continuity and it seems like all the voltage is there 

 

[RDspaguy]

12 minutes ago, Dean093 said:

I checked the continuity and it seems like all the voltage is there 

 

????

Continuity and voltage are two different settings on your meter. Check voltage at the heater terminals on the circuit board (where the red and black wires from the heater connect, low left on board). What is the voltage between the two wires?

[RDspaguy]

Or did I misunderstand, and you checked both voltage and continuity? If so, what voltage and how many ohms?

[CanadianSpaTech]

Likely not related but that F2 fuse (white paper fuse horizontal one on right hand side) is barely hanging in there

[Dean093]

I checked both I couldnt get a voltage reading but the continuity was there

[RDspaguy]

If you have a heat indicator, no errors, and no voltage between the wires going to the heater then you have a bad relay on the board.