how to lower water temp

plb

i have a burnham oil boiler from the 1970's originally used for radiant heat and hot water, now only used for hot water, setting is at 180, would like to lower to 140, it has a honeywell box, is it ok to lower temp?  how low?, is there a site on how to lower the setting?  thanks, pb

Zman

Indirect?

It sounds like you have an indirect coil in the boiler? Or a separate indirect tank?

Care should be used to not lower the temp to the point that the boiler condenses.

Can you post a picture of the controller and the boiler piping? 

Empire_2

140*

140*f is the cut off at which condensation can occur.  ORC would be great to control your boiler operating temps when warmer weather comes.  Control should only be adjusted by qualified Professionals.  You don't want your system rotting away.  Having said that, a 1970's boiler does not owe you any money so if you would like to save on fuel bills there is a ton of new equipment designed to do just that. 



Eugene, chime in if you would.





Mike T.

plb

pictures of unit

hope this helps, plb

Zman

There is

There is a high limit (don't touch) and an operating stat inside the gray box. If you decide to lower the temp you need to observe the boiler return temps under full load to be sure you are not condensing the boiler. Your returns should not be below 140. You may be able to go as low as 150 on the operating stat. If you are all uncomfortable with electricity or the operation of the stat, call a professional.

If I were you, I would start making plans for a new unit. Your setup is a very inefficient way to make heat and hot water. With little insulation and no flue damper so you are heating the room and the outdoors as well as the water.A new condensing boiler would save 30-50 percent easily.

Zman

Demand heater

I just noticed that you no longer heat with this unit (intentionally). A instantaneous heater might be a better call.