non condensing boiler reset

777

If you want to add reset control to a non condensing boiler what is the lowest recomended water temperature to run it at? 140 degrees F seems to stick in my mind like that is the lowest temperature that will guarantee no condensing but I'd like your input.

Another question: what is the best insurance against thermal shock and how do you really define thermal shock? I've heard of bypass and shutting off the circulator until water temperature reaches 140 as some of the more common measures to prevent shock.

CMadatMe

Wouldn't Reset

I wouldn't reset the boiler lower than the recommended return water temp which is generally 140 degrees for a cast iron boiler.



I would add an outdoor reset control for the boiler and limit the return sensor (boiler protection to 140 degrees). I would also primary secodary pipe or use a hydro separator. I would then reset the system side to the lowest possible water temp.