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Boiler Not Turning On At Low Set
I have a Peerless tankless hot water system. Used for heat and hot water. The aquastat went the other day. I replaced the aquastat and also the mixing valve while I was at it. I have the aquastat set to 160 low / 180 high / 15 Diff. The boiler temp drops to 125 - 130 before it fires again. I checked the thermo capillary bottoms out into the well. The tube is brand new. I didn’t kink or damage it. Was very careful. Shower starts hot. Then gets warm to barely warm. Am I missing something obvious? Thanks for any insights.