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Honeywell L8124A

pipemd Member Posts: 3
I just converted an oil fired boiler from a tankless coil to an indirect fired water heater with priority zoning off a new switching relay. The existing boiler uses a honeywell L8124 triple aquastat that had been set up "on temperature". I would like to set the boiler up as a cold start. I recall rewiring one of these aquastats a few years back with just a couple of leads moved around to get the triple aquastat to operate as just a boiler high limit. I just can't remember what I did.

Anyone familiar with this?


  • JStar
    JStar Member Posts: 2,752
    edited October 2010
    Just one wire.

    Remove the plug for the low limit, highlighted by the red circle in the picture. It should go from B to ZR.
  • billtwocase
    billtwocase Member Posts: 2,385
    I would

    keep it a warm start. Set the low limit as low as it will go. There will probably always be some temp on the boiler anyway. Cold start is not always as good as it sounds. What boiler do you have? 
  • Ron Jr._3
    Ron Jr._3 Member Posts: 603
    I agree with Bill

    With an indirect connected the boiler will probably not go down to ambient temp . Was watching my own boiler / indirect and the temp was around 115 at 6 am 3 days in a row in summer .  

    I'd do like Bill said and set the low limit as low as it'll go . Set the differential as high as it'll go for even more off time .
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