HELP with ERROR CODE: HEATER IS TOO HOT

[crblove]

Looking for advice on an Artisan Islander HOT TUB with an Error code that says "heater is too hot". We have replaced the two temp sensors & it still "overheats" or displays the above error. TIA

 

[ajw22]

Welcome to TFP.

@RDspaguy may have ideas when he wanders by.

 

[RDspaguy]

Remove your filters. If it stops showing the error, thoroughly clean or replace filters. Dirty/clogged filters slow the water flow through the heater causing it to overheat IN THE HEATER, but not in the tub.
If this is not it, post pics of the circuit board, wiring diagram, and equipment area so I can see what you've got in there.
Do you have a multimeter?