Steam vs hot water Radiator Valves

itzasean

So I have a couple rads that have shut off valves from Home Depot that I was told are for a hot water system. I do have some steam valves that are just a little fatter but I cant tell the difference between the different valves with the way they perform. Can someone explain?

Jamie Hall

There are critical differences inside the valve. The steam valve is built in such a way that water can drain freely and completely through it when it is opened. The hot water valve is built somewhat diffeerently, and has a smaller opening (sometimes much smaller) and unless the valve is oriented just so will not let water (condensate) drain back through it readily, even if it is opened.

dko

Are you sure you didn't just buy a steam radiator valve and the guy just said it'll also work for hot water? (you can- preferably the white ptfe disc, just not vice versa)
I don't see home depot have any hot water radiator valves in stock

but here's a youtube video showing the difference

https://www.youtube.com/watch?v=sAPK_txfTxQ

ordellrobbie

I think you can use a steam radiator valve on hot water. You definitely can’t use hot water on steam.