Foil tape to shrink air vent hole size on steam radiator

mike212

My house has a small bedroom with a large radiator that overheats the room to the point where its better to cover the air vent completely than to leave it on and sweat out its occupants. Without any heat the room still remains comfortable as its well insulated. It would be nice to have it take in some heat though on the coldest days. I've tried a using a thermostatic air vent but despite lots of tinkering I can't seem to get it to a comfortable level. Recently I found a hack that seems to work well, just want to run it by the group to make sure I'm not creating some unforeseen problem…

I've used some foil tape (the type used on ductwork) to reduce the hole size of the radiator's air vent (Gorton #4) to a size much smaller than anything available on the market. It only seems to start letting air out of the radiator only once pressure builds slightly over 0 (after most other radiators in the house are already very hot). This is generating the desired effect of just heating that radiator slightly and only when the boiler has ran enough to build up pressure slightly. The pressuretrol is set as low as I can get it - to roughly 2.0 and its not until I'm seeing pressure in that 0.5 to 2.0 range that I feel any heat in this radiator now.

I haven't seen this mentioned anywhere so I just want to make sure I'm not causing some unforeseen problems in my system by managing the heat in that room this way.

jesmed1

The foil tape with pinhole has been done elsewhere. See @leaking 's first comment below. I'm not a heating pro, but none of the pros on the previous thread seemed to object.

https://forum.heatinghelp.com/discussion/comment/1823882#Comment_1823882?utm_source=community-search&utm_medium=organic-search&utm_term=vent+foil+tape

ethicalpaul

Yeah it's no problem. But I will say a #4 is already very very small. If that one is getting too hot that tells me the venting on your other radiators might be too small. But you are in a better position to know than I am!

You could also consider putting a 1/8" ball valve (yes they make them) before the vent to choose when you want heat.

mattmia2

Just make sure it isn't so small that air can't get in on the off cycle or you could end up collecting condensate in the radiator.

ethicalpaul

Well that's not true (although it is a commonly-held belief). Condensate doesn't need air in the radiator to drain, otherwise how could they have worked during the coal days when the fire was on all day?

To expand on this, the pressure (whatever it is) is the same in the runout pipe and in the radiator. Condensate just runs out fine regardless what the pressure is.

Additionally, even if it did matter (it doesn't), air will come into the radiator from the main. A radiator won't hold a vacuum against the main.

pecmsg

Just throw a blanket on the radiator.

leaking

I’ve done the foil tape /pin hole , for 20 years and no issues. As long as air releases it gets some heat , if you need more reduction put vent on top not the middle and make a radiator cover . Or as another person said put a blanket on it .

JH3550

Maid o Mist has an adjustable attachment for their vents and it has a setting smaller than #4 (which I believe is similar to Gorton #4). I have a few of them, and I like them. It uses a ball valve that is easy to adjust, and you can also turn it off.