Interesting situation. I two Raypak 406a heaters (one for pool and one for spa) connected to a Jandy AquaLink RS dual 2/6 system. Problem started with the spa heater reading a clock/fireman switch error. Seemed like a wire was loose on the Jandy 6586 mini-board that attaches the Jandy AquaLink RS and controls the spa heater. But then heater was failing to light still and giving a no pilot sensed / ignition lockout message. I called gas company and they ended up replacing the main board, the gas valve and the transformer, as well as cleaning the pilot assembly, on my heater. When they finished, the error remained and they said gas valve was bot getting sufficient voltage. I swapped out the 6586 with another board and everything seemed to work. But when heater reached it maximum heat, it started generating a high limit 2 error and shutting down. Turning unit off and back on restored (actually just pushing the mode button to off and back to spa was sufficient).
One other thing to note. Spa heater is 10 years old. About 6 years ago I noticed a 3 degree difference between the temperature sensor on the heater and the Jandy sensor in the spa. While the Jandy called for 104 heat, the heater would stop heating when it thought it reached 104, but this was really 101 in the spa (documented by external thermometer too). To compensate for what I presumed was a faulty temperature probe, I have set the heater to heat to 107 maximum. This had never been an issue until now. As it turns out, the spa heater seems to hit the high limit 2 at 107 degrees, but does not seem to generate the error message, at least so far after two days of testing, at 106 (which gets my spa to 103). I have a replacement temperature probe which I will install in RayPak this week to see if it corrects the temperature reading issue.
UPDATE: Actually the high limit 2 came on again this morning with unit set at 106. Seems that every day the spa heats up (today from 80 to 98 on the Jandy) then shuts with a high limit 2 error. Raypak says to press "mode" to reset limit. Upon pressing mode twice (once to off, once back on) the heater works again and heats to desired temperature.
Question, can setting the Raypak 406a at 107 be the cause of the high limit 2 error, or might something else be going on. These errors never came before the board and gas valve were replaced.
One other thing to note. Spa heater is 10 years old. About 6 years ago I noticed a 3 degree difference between the temperature sensor on the heater and the Jandy sensor in the spa. While the Jandy called for 104 heat, the heater would stop heating when it thought it reached 104, but this was really 101 in the spa (documented by external thermometer too). To compensate for what I presumed was a faulty temperature probe, I have set the heater to heat to 107 maximum. This had never been an issue until now. As it turns out, the spa heater seems to hit the high limit 2 at 107 degrees, but does not seem to generate the error message, at least so far after two days of testing, at 106 (which gets my spa to 103). I have a replacement temperature probe which I will install in RayPak this week to see if it corrects the temperature reading issue.
UPDATE: Actually the high limit 2 came on again this morning with unit set at 106. Seems that every day the spa heats up (today from 80 to 98 on the Jandy) then shuts with a high limit 2 error. Raypak says to press "mode" to reset limit. Upon pressing mode twice (once to off, once back on) the heater works again and heats to desired temperature.
Question, can setting the Raypak 406a at 107 be the cause of the high limit 2 error, or might something else be going on. These errors never came before the board and gas valve were replaced.
Last edited:
