Aqua stat setting

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Bbillcee

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I have this Honeywell l4006a aquastat on my weil mcclain eg50 boiler.....the boiler used to have a coil for domestic hot water that i am no longer using. The dial is set to 160 and i see a "5" on the differential wheel. Do these settings seem correct for just using this as a heating system now?

Now that there is no coil being used would it make sense to disconnect the aqua stat altogether or should keep it so the boiler doesn't have to cold start?

here is a link to the aqua stat i have

https://www.supplyhouse.com/Honeywe...MI_bzvn9SQ3gIVGUsNCh3JmwzwEAQYAiABEgIWu_D_BwE
 
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Jadnashua

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You need to have the boiler temp set to provide the needed load and manage the return temperature. Not sure on that boiler (but it should be in the operational manual). Depending on the radiation, you may not need it to run that hot, and may be able to allow a bigger differential. Would need to know more about the system and how it is heating the home - type of radiators, heat load, etc. Some boilers can handle cold starts, some are not designed for it.
 

Bbillcee

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You need to have the boiler temp set to provide the needed load and manage the return temperature. Not sure on that boiler (but it should be in the operational manual). Depending on the radiation, you may not need it to run that hot, and may be able to allow a bigger differential. Would need to know more about the system and how it is heating the home - type of radiators, heat load, etc. Some boilers can handle cold starts, some are not designed for it.

this is a one pipe steam system, cast iron radiators
 

Dana

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There's no point to keeping a gas fired steam boiler hot 24/365 even when there's no heat load. Some older steam boilers, particularly some oil-burners will leak if allowed to get cold. If it's a terra-cotta lined flue an oil boiler can have excessive and destructive flue condensation if fired for extensive amounts of time below 140F. Worst case, turn it down to 140F and still suffer the (now lower) standby losses for half a year.

With a model name/number of the boiler and a better description of the flue it might be possible to advise a bit more precisely.
 

Bbillcee

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There's no point to keeping a gas fired steam boiler hot 24/365 even when there's no heat load. Some older steam boilers, particularly some oil-burners will leak if allowed to get cold. If it's a terra-cotta lined flue an oil boiler can have excessive and destructive flue condensation if fired for extensive amounts of time below 140F. Worst case, turn it down to 140F and still suffer the (now lower) standby losses for half a year.

With a model name/number of the boiler and a better description of the flue it might be possible to advise a bit more precisely.
 

Bbillcee

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weil mcclain eg 50 - natural gas.....i think aqua stat was solely for the coil...i could be wrong
 

Dana

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weil mcclain eg 50 - natural gas.....i think aqua stat was solely for the coil...i could be wrong

See if the control schematics look at all similar to what you have. Compare the with-tankless control scheme to the no-tankless version, and see if you can set it up like the no-tankless flavor.

Cold starting this boiler shouldn't be a problem, but if you let it go stone-cold during times of mild weather keep an eye on whether there's a drip-drip going on under the boiler. Probably won't be, but if there is you may need to keep it at least warm-ish , say 120F to keep that from happening. Extensive burns below 125F could eventually corrode the fire side of the heat exchanger plates with condensation, but if it's just maintaining temp over the summer it won't add up to much condensation. Almost all gas boilers cold fire just fine, and if yours doesn't leak when cold, that's the way to run it.
 

Bbillcee

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See if the control schematics look at all similar to what you have. Compare the with-tankless control scheme to the no-tankless version, and see if you can set it up like the no-tankless flavor.

Cold starting this boiler shouldn't be a problem, but if you let it go stone-cold during times of mild weather keep an eye on whether there's a drip-drip going on under the boiler. Probably won't be, but if there is you may need to keep it at least warm-ish , say 120F to keep that from happening. Extensive burns below 125F could eventually corrode the fire side of the heat exchanger plates with condensation, but if it's just maintaining temp over the summer it won't add up to much condensation. Almost all gas boilers cold fire just fine, and if yours doesn't leak when cold, that's the way to run it.
thanks a lot......from what i can tell the aqua stat is only used for DHW and there is none on the model without the coil. In the summer i turn the boiler off!
 
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