Replacing loop seal on my return?

kacrejamReturns

I have a wet loop seal/water seal right near the end of my steam main. The loop is leaking a bit and i think i should replace. Should i consider using a steam trap or just replace kind for kind?

Jamie Hall

Just replace it.

Steamhead

https://forum.heatinghelp.com/discussion/comment/1903768#Comment_1903768

Agreed. Why add moving parts? The Dead Men didn't need a trap there………..

EBEBRATT-Ed

I agree don't mess up something that works. loop seals work well. If you replace piping below the water line copper is ok if it is easier.

mattmia2

the crossover trap is only a trap instead of fittngs because it needs to be able to vent air out of the main in to the return.

109A_5

I'd just repair it. However if you get ambitious you could set up the bottom so it is more serviceable with better clean out capability.

kacrejamReturns

Thanks all, very much appreciate. I will replace and try to make it more serviceable.

Steamhead

@kacrejamReturns , serviceability can be something as simple as a ball-valve boiler drain at the bottom, which would let you flush dirt out.

STEAM DOCTOR

Replace. Like for like. If this was my job, I would definitely use copper. Won't accumulate sludge like steel and iron. Use brass in between the copper and the steel

Mad Dog_2

We always install a Gate Valve with a tee and 3/4" Boiler drain below the water line, whether its the Hartford Loop or a loop seal (install one on each leg) Its the best way to be able to blow out and Muddy Splunck that congeals at all the low points of a Steam system. We will use a ball valve in a pinch, but the Teflon ring inside them dont hold up long in the superhot steam condensate. Mad Dog

simon_skove

Is it advisable to take apart the loop just to service it …I am pretty sure the two loops on my two pipe system have never been cleaned.

Thanks.

Mad Dog_2

Screenshot_20260926_072447_Gallery.jpg

If you do them like this, you can power-flush 'em out down the road, and the mud and splunck have no chance to collect. Mad Dog

Jamie Hall

first place, there isn't that much condensate involved, and second place the condensate is basically distilled water. If you have mjor surging or a way overfilled boiler at some point, maybe…

EBEBRATT-Ed

Or just use two unions. You can take the whole thing off to clean it.

kacrejamReturns

I needed to add a third union. Thought to share the horror of the sludge i found during replacement!!

109A_5

Now you see first hand why clean outs help with system performance. Although that is probably many many years of accumulation.

Thanks for the pictures !!!