8182 aquastat DIFF question

steamnoob

I disconnected my tankless coil in the summer of 2019. That season, I turned the LO and DIFF all the way down, and turned the boiler off during the summer. Last summer, by chance, I saw wiring instructions inside the aquastat cover to jump out the LO function. This season, I seem to be having a bit of a short cycling problem, boiler firing up for less than 5 minutes, every 10-15 minutes when called, usually to supply a baseboard zone in kitchen. Does the DIFF dial have anything to do with this, or is the HI differential setting "hardwired"

EdTheHeaterMan

On the L8124 controls, the High limit has a fixed differential of 10°F there are no other adjustments for that control for your short cycling. I'm not one to advocate a change in a part or control unless absolutely necessary. That said if you were inclined to replace the L8124 control with a digital version there is a setting known as ACS "Anti Short Cycle" that may address the situation. Is this on an oil fired boiler? The control I recommend is the L7224U in the case of an oil fired boiler.

Some may advocate the Hydrolevel brand digital control for the Low Water Cut Off (LWCO) feature, BUT... you also need to replace the well adaptor. This means draining the boiler to re-fit the proper well adaptor. Not worth the effort in my opinion.

You can live with the short cycling, or you can do something about it. I don't think it will make a big difference either way.

HVACNUT

@EdTheHeaterMan, the OP stated the L8182 aquastat which is also the cad cell primary. It's the size of a suitcase. So any change out would need a new primary as well.

EdTheHeaterMan

@HVACNUT I did not see that, All the more reason to stick with the existing control.

However, if the OP needs to swap out the old combination Protecto-relay/Aquastat, in the future, the L7224U plus Carlin 70200 and a 1900 box is still less expensive than the exact replacement in my experience.

Either way, the triple aquastat portion of the control works the same.

steamnoob

Sorry, I should have said its an R8182 aquastat (not suitcase sized). thanks for help. need an upgrade whole system eventually, so will live with short cycling. Just wanted to make sure wasn't something I could do with the setting.