Condensate in a Standard Tract House Atmospheric Boiler Installation During Fall Weather

allthumbs

I have read discussions pro-to-pro regarding condensate with low return temps. I couldn't find the answer I need. I use my atmospheric hydronic boiler during the fall. It quickly satisfies the thermostat, and the return temp is always less than l30 degrees at shutdown. In the winter, the return temp. is always above 130 at shutdown. The boiler is a 35 year old Utica. Should I avoid heating the house during the Fall?

EBEBRATT-Ed

If your boiler is 35 years old and you have no damage signs from the condensate so far then your probably ok

It's normal for the return water to be below 130 on initial start up but you don't want to run the boiler continuously or for long periods of time with 130 deg or colder return water.

If you were getting condensate damage you would usually see:

Deterioration of flue pipe
Rust stains on the boiler jacket or running down the boiler jacket, especially around the flue pipe.

And you would usually see white deposits around from the calcium in the flue gas condensation

If you post a few pictures we could take a look

Jamie Hall

Pictures are always good... one might ask, though, what are the output temperatures? And what kind of flow rate is being used? It might be possible to tweak either the flow or the output temperatures -- or both -- to get the return temperatures to come up.

dopey27177

If this a water heating system I would raise the aquastat temp to 190 with a 20 degree differentialto try to get the return temperature ti 140 degrees.

Jake

STEVEusaPA

Down the road, when it's time to replace, make sure they pipe it for boiler protection, unless it's a Mod/Con.

hot_rod

Gas or oil? Metal vent pipe or masonry chimney?
Ideally the boiler should be operating out of condensing temperatures within a 10 minute run time. 10 minutes or more run time is preferred to get to steady state efficiency, dry out the flue, etc.

Watching the entire run cycle on a mild heating season day would show you if it is "dripping" condensing, insides. Making sure the flue piping warms sufficiently can be a bit tricker.

mattmia2

Increase the anticipator on the t-stat to make it run longer cycles?

Maybe the heat that is still in the boiler from the last cycle is enough to satisfy the t-stat. Maybe use a 2 stage t-stat, first stage runs the ciruclator, if it doesn't satisfy after 5 or 10 minutes, second stage fires the burner.