Closing radiators to save fuel

Frank M. Tricarico

Need an answer from the experts!

I have a large old 100+ year old house which is heated by gas and uses a low pressure steam system - two pipe.

I would like to shut all the radiators off on the third floor and about 4 or 5 on the second floor.

If these radiators are off there would be no steam and therefore no condensate return. I would think that the third floor would be no problem but am unsure of closing half of the second floor.

Should I be removing the traps and checking if there is any old condensate in the radiators or just assume it will be okay.

Any advice gratefully accepted.

Thanks

Steamhead

I wouldn't shut off

the heat in the bathrooms, or any other room that has plumbing in it. Some heat is needed to prevent mold and freezing.

You might want to look into installing Thermostatic Radiator Valves in the rooms you don't normally want to heat. These can be set to any minimum temperature you want.

The traps should not be a problem. Most or all of the condensate drains from the radiators and traps when the steam is off.

Big Ed

Shut Off

I don't see any problems with the heating system other then the boiler will be too big for the system. Just remember you still need to keep the house plumbing from freezing.....

Christian Egli

The graduated heat provided by two pipe systems

With two pipe systems, there is no problem either closing the radiator valves partially only.

Check to make sure there are such things as float and thermostatic traps or vents at the end of the mains. There might also be some cross-over traps. These will be critical on your system if you close many radiators. These might never have been there, they might also have been unwisely removed.

This is why: with two pipe systems and no end of main trap, all the air from the system mains exits through the radiators, the radiator traps, then the returns, and finally some hole somewhere in the basement. In which case, closing the radiators will also cut the main venting.

If this situation applies to you, then reinstall the end of main traps. Or, at least leave the last radiator on the branch wide open so the whole main can be vented through it.

If your system never had any main traps or vents, then you can install Gorton no. 2 vents on the mains. This will greatly improve start up speed.