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Need replacement aquastat for L4080B 1105
Need a replacement for old aquastat L4080B 1105, on a late 1960s Hydrotherm HC100 propane Boiler. No domestic hot water made by this boiler, just hydronic baseboard heat. Circulator control is R8845U 1003.
I suspect a faulty aquastat causing extreme short cycling. I'd like an aquastat with a larger adjustable differential.
As an aside, what does the little lever do as indicated by the red arrow in the picture?