Aquastat

MikeM · Post by **MikeM** » Mon. Dec. 30, 2019 7:42 pm

Went from a Honeywell L8124 to a L7224 on my buddy's efm 520 and now it won't hit the high limit....the thermostat gets satisfied and it stops the blower/feed before the high temp gets reached.....

Any ideas

Thanks.

Mike

Post by **StokerDon** » Mon. Dec. 30, 2019 7:48 pm

Welcome to the forum.

I don't see the problem??? The stoker should never, ever run up to the high limit after the heat call is satisfied. Maybe there was a problem with the old aqauastat?

-Don

MikeM · Post by **MikeM** » Mon. Dec. 30, 2019 9:08 pm

Had a power surge and it fried the 8124.....it always shut off on the HL of 180 with the 8124......set the digital limits on the 7224 just like what were on the 8124...and even when the t stat was satisfied it would go to the HL...but now with the new digital one the tstat shuts it down...thus the need for the timer...or so we thought.....

The 8124 aquastats are on 2 other units and the temps on mine and my buddy's other 520 always go to the HL then shuts off

2001Sierra · Post by **2001Sierra** » Mon. Dec. 30, 2019 9:26 pm

It is behaving as if it is programmed for a "cold start" boiler application. In a cold start boiler the aquastat only turns on when there is a call for heat, thermostat or indirect water heater.

MikeM · Post by **MikeM** » Tue. Dec. 31, 2019 5:10 am

Ok, I see where that is an option and will verify after work to make sure it is not set up for this "coldstart".

Mike