Hello. I moved into this home last November. I haven't had any success with heating the spa. Allow me to take you down the path...
The first issue I had was when it Called for Heat I smelled gas. The pilot unit was completely rusted! I replaced the pilot. No longer smelled gas and was getting the "flame icon". However, it still wasn't heating. I noticed there was not any water flowing through "spa return" when looking at the check valve. The same time the pressure on the filter was high so we did a back flush, cleaned out all the in-ground filters. This relieved the pressure and now I can see water running through the spa return check valve window.
Now the heater will show spark, then calls for heat, and the flame icon shows and then resets/repeats the cycle.
The first issue I had was when it Called for Heat I smelled gas. The pilot unit was completely rusted! I replaced the pilot. No longer smelled gas and was getting the "flame icon". However, it still wasn't heating. I noticed there was not any water flowing through "spa return" when looking at the check valve. The same time the pressure on the filter was high so we did a back flush, cleaned out all the in-ground filters. This relieved the pressure and now I can see water running through the spa return check valve window.
Now the heater will show spark, then calls for heat, and the flame icon shows and then resets/repeats the cycle.