I have Triple AQUASTAT relay L8124A Honeywell controller on my hydronic heating boiler. It is setup like this for hot water heater as well. I don't have use it for hot water, I have electric hot water heater. How do I stop it from running the boiler to keep the temp for the hot water. I only want it running to provide heating and operate by room thermostat, by not for hot water.

If I turned down the low to 120 or whatever the lowest is, and Diff as well lowest set, will it eliminated the DHW coil? How it will affect on heating?

Could I, some how, bypass the Lo limit or disconnect wire from sensor?

Can you advise? Thanks!

  • Is your domestic hot water through a tankless coil in the boiler, or through an indirect tank? – ThreePhaseEel Oct 11 at 22:41
  • Looks for me like simple copper coil in the boiler, it's not indirect tank. – Michael Oct 13 at 4:17

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