what's a concentric bushing?

R. Kalia

We have a 2" (both sides) radiator valve that I want to replace with a TRV. Plumber says "no TRVs that size" and offers no other solution.

The right-angled TRV (say 1.25") would, of course, have female ends, while the 2" pipes are male. I need to reduce the pipe size without extending the pipes, because if I change the lengths, the TRV won't fit.

Any explanation of how I would do this with a concentric bushing (or otherwise) would be greatly appreciated. As you can see from the language above, I am an amateur, but apparently so is our plumber.

Tony_8

huh ?

Sorry, a concentric bushing won't help. You'll need to cut and rethread the riser to reduce it. Concentric means the inlet and outlet are centered, eccentric means one is offset from the other. You probably should use a reducing coupling, not a bushing also.

gerry gill

I wasn't going to reply since you slammed your plumber,

but okay, i'll ask...do you have one pipe steam or what i am thinking is two pipe air vent from your first paragraph's descrition?

Mike T., Swampeast MO

Since most iron rads had 2" tappings, you might have some problem as a reducing bushing will increase width a bit and 2" pipes aren't likely to have much "wiggle room".

I'm presuming the lines come through the floor. Replace the riser pipe to the supply side with 1" (shouldn't be too bad a job), install a 2" x 1" bushing in the rad, use a 1" TRV and [I think] everything should fit nicely. Do though verify those sizes. The old bushings didn't stick out as far as most of the new bushings and you might have to drop down to ¾" to get everything to fit easily. Then verify that the ¾" TRV has sufficient flow capabilities--unless that rad is absolutely enormous it will...

R. Kalia

Hot water. And not everyone is knowledgeable just because they work in the field.

Weezbo

its like a concentric bell reducer:) except different:)

Victor H Plank

radiator valves

> We have a 2" (both sides) radiator valve that I

> want to replace with a TRV. Plumber says "no TRVs

> that size" and offers no other solution.

>

> The

> right-angled TRV (say 1.25") would, of course,

> have female ends, while the 2" pipes are male. I

> need to reduce the pipe size without extending

> the pipes, because if I change the lengths, the

> TRV won't fit.

>

> Any explanation of how I would

> do this with a concentric bushing (or otherwise)

> would be greatly appreciated. As you can see from

> the language above, I am an amateur, but

> apparently so is our plumber.

S Ebels

UUUUuuuuuuuuuummmmmm

A reducer that's not eccentric!!!!

Sorry I couldn't resist (G)

Alan(CaliforniaRadiant)Forbes_2

Seems as though

you are doing (or have done) a gravity conversion, that is, changing your old gravity system to a system with a circulator..............and you're adding TRV's to balance the system.

I had the same problems you have now; 2" radiator piping and the largest TRV's are 1-1/4". Luckily, the radiator supply was piped to the top of the radiator, so we had a lot of room to cut and thread the supply down low, install a 2" x 1-1/4" bell reducer, nipple and TRV along with a 2 x 1/4" bushing in the radiator.

The right-angled TRV is actually male, so you shouldn't have any problems; the fit is perfect. We used Danfoss TRV's.

The only difficulties we had were 1)threading 2" pipe in place, and 2) one of the radiators was piped in reverse and the TRV slams shut when the temperature gets close to setpoint.

Weezbo

he he he i also felt a twinge of the deamons glee:)

esscentialy resistance was Futile:) as the borgs say:)

S Ebels

What you are after is

Called a face bushing. It has no shoulder or hex on it. It's simply a double tapped, threaded ring. I've never seen one that drops two sizes and they are not a very common part in the first place.

flange

i believe concentric means that you keep your centers in the middle!