Thread: boiler providing steam heat and hot water heat

Ran across a situation with an oil fired boiler that is providing steam heat to the old portion of the home and supplying hot water to the hydronic units in the new portion.

The boiler is located in the basement of the older section of the home.

Currently the new section with the hydronic units will not heat up until the old section with steam heat is up to the set temperature. Why is this happening and is it common?

Similar Threads:

• Mismatched Lennox heat pump and high temp diffs
• Heat Pump?
• Deposit on boiler vent
• Age for Weil-McLain Boiler?
• Magic Heat

Hi Peter. I think we have met a couple of times at education classes.
Check out this forum at Heatinghelp.com
I would ask the question there if no help is forthcoming here. Good luck.
HeatingHelp.com's The Wall

I imagine the reason that the reason the hot water portion of the house will not heat until the steam boiler is up to the temperature that it is making steam is because there is a steam to hot-water converter that requires steam to make the water in the converter hot. This is normal for this type of system.

The condensate trap for the converter could also not be working properly so the steam side of the converter is full of water so it is blocking the steam from getting to the converter.

Originally Posted by Peter Ottowitz

Ran across a situation with an oil fired boiler that is providing steam heat to the old portion of the home and supplying hot water to the hydronic units in the new portion.

The boiler is located in the basement of the older section of the home.

Currently the new section with the hydronic units will not heat up until the old section with steam heat is up to the set temperature. Why is this happening and is it common?

It's probably as intended to so that there is first steam available before providing hot water for the hydronic portion. Other wise the system may never get hot enough to produce steam or at least it would be much slower to do as the BTUs are being used to heat the hydronic system. There must be control valves and temp sensors to accomplish what you describe.

added: I see James answered while I was typing.

I've not seen a combination unit as you describe but have seen hydronic systems which would not heat upper floors due to air being trapped in the upper zones.