Hi Everyone-
I recently had success fixing High Limit 2 error and wanted to provide some insight. First, my heater is the 406a with fresh water pool that is on 5th season this summer. Last year, the spa would heat up to about 98 degrees then start throwing the high limit 2 code. It would cycle on and off less then a minute and took additional 25 minutes to heat up to usual 103 temp we have set. Frustrating as it takes much more time and cycles on / off.
I replaced the thermostat but no change. Then, I pulled the manifold off and replaced the internal bypass (says silver spring for 406a) and also replaced both high limit sensors. Before putting it all back together, I added some high temp fireplace insulation to tin shield and made two galvanized clips from joist type of hanger / ties. Bent then in half like a clothes pin and it worked great. All perfect now and it heats right to 103 or 104 if set to that temp.
My experience is that the heater seemed to be in pretty poor condition. It is a shame since it is not very old. I don’t feel it was the internal bypass as that seemed fine. If I could do it over again and to save some time, I would have just pulled the top cover, additional manifold tin cover and replaced the high limit sensors / insulate the tin cover as mentioned by many. Easy and inexpensive first step and I am very certain this was the issue. Maybe the sensors were just heated on the outside so many times that they did not insulate as well or had hairlines cracks. But due to the inexpensive price to replace both, that would be my first step next time with these same high limit errors that many seem to be having.
Pics included show the rush on bottom pan of burner stand along with the clips / high temp fireplace insulation added to tin cover.
Hope this helps.
Dave
I recently had success fixing High Limit 2 error and wanted to provide some insight. First, my heater is the 406a with fresh water pool that is on 5th season this summer. Last year, the spa would heat up to about 98 degrees then start throwing the high limit 2 code. It would cycle on and off less then a minute and took additional 25 minutes to heat up to usual 103 temp we have set. Frustrating as it takes much more time and cycles on / off.
I replaced the thermostat but no change. Then, I pulled the manifold off and replaced the internal bypass (says silver spring for 406a) and also replaced both high limit sensors. Before putting it all back together, I added some high temp fireplace insulation to tin shield and made two galvanized clips from joist type of hanger / ties. Bent then in half like a clothes pin and it worked great. All perfect now and it heats right to 103 or 104 if set to that temp.
My experience is that the heater seemed to be in pretty poor condition. It is a shame since it is not very old. I don’t feel it was the internal bypass as that seemed fine. If I could do it over again and to save some time, I would have just pulled the top cover, additional manifold tin cover and replaced the high limit sensors / insulate the tin cover as mentioned by many. Easy and inexpensive first step and I am very certain this was the issue. Maybe the sensors were just heated on the outside so many times that they did not insulate as well or had hairlines cracks. But due to the inexpensive price to replace both, that would be my first step next time with these same high limit errors that many seem to be having.
Pics included show the rush on bottom pan of burner stand along with the clips / high temp fireplace insulation added to tin cover.
Hope this helps.
Dave
