TRV at a 90°

jrodricks

All of my single-pipe radiators are oversized, but the biggest offender (if you'll pardon the pun) is in the kid's room. Because of that, I'm planning on putting a TRV on that one.

The air vent is tucked in the corner so there's no room for a TRV. There air vent end of the rad is about 4" from the wall. I was thinking I'd use a couple 1/8 NPT elbows and short extensions to get the TRV out of corner. I assume a few 90° elbows and say 4" of extensions won't hurt anything on an air vent. Is this correct?

I'm talking about a left turn. I know the TRV has to stay parallel to the floor.

jrodricks

Here's a photo.

ChrisJ

Well, first things first.

Get rid of all of your Heatimer Varivalves. There's even a chance you'd get that monster under control using a Gorton 4 or 5.

However, a TRV should work fine like that but try to keep it pitched back towards the radiator so any condensate that gets in it can drain back. Not much, just a slight tilt backwards, barely noticeable. I'd install a reasonable vent on it as if you vent too quick you're going to find the TRV can't react fast enough and you're still cooking your family. I've found Gorton 4s and 5s work well on them but think I have a Gorton 6 on one just because of the pressure drop from the piping.

Please, don't even bother with the vent you currently have, even on the slowest setting it's way too fast for a TRV to react.

Just make sure you get the straight Gorton, not the right angle. They're gold color instead of chrome.

ChrisJ

Here's one of mine.

KC_Jones

I agree with Chris on this one. Something you could try before spending a bunch of money on the TRV is get a short nipple and a 90° elbow and mount a straight gorton #4 on it to see if a slow vent helps out, if it doesn't work you can reuse everything you bough on the TRV including the elbow. Those Heatimer vents are gigantic on it's lowest setting it is about 2.5-3 times the flow of a Gorton #4 vent.

jrodricks

Thanks guys. I ordered a Gorton #4.

The Varivalves are from the local oil co.

ChrisJ

jrodricks said:

Thanks guys. I ordered a Gorton #4.

The Varivalves are from the local oil co.

Figures, they want you wasting fuel.
I'd switch all of your vents over to Gorton and make sure you have ample main venting.