What is this fitting?

FranklinD

Hello friendly (and all-knowing) Wallies...

So I'm relocating my expansion tank, since the original installer A) made it almost impossible to remove - caged in by other pipes, left it hanging from a pipe unsupported, and C) failed to install an isolation valve, should it need service mid-season.

I removed it from its original spot, screwed into a T on the underside of the air separator. My question is, what is the brass fitting pictured, and should I leave it in place when I reinstall it? Is it just to prevent crud from falling straight down onto the diaphragm from the separator? It has an oring at the tip so I am confused.

Thanks for any help you can provide!

Andy

FranklinD

Huh. I did not realize a capital "B" and a right parenthesis made a "cool sunglasses guy" emoticon. Oops.

FranklinD

Okay...I think I may be an idiot. I didn't realize this was a Honeywell tank, and was looking at the literature for an Amtrol.

Upon reading thru Honeywell's submittal sheet, this appears to be a check valve that would allow you to replace the tank without draining the system. So that an isolation valve isn't needed. They apparently also recommend hanging the 4.4 gallon tank from the air purger just as it was.

Okay, now. Something with that just doesn't sit right with me. With 130-140 gallons and 20 feet of altitude sitting on that tank connection, I don't know that I'd even want to try changing a waterlogged tank with just the check valve protecting me. Seems....weak.

I also don't care for having that tank just hanging around, unsupported, from a span of piping. It's location also makes it impossible to remove the top of the boiler for inspection & cleaning.

So is my plan to relocate the tank 3 feet away, on a wall bracket with an isolation valve, okay? I can't think of any reason it wouldn't be.

Sorry for answering my own question. I wasn't expecting to see an odd fitting upon unscrewing the tank.

Andy

Eric_32

That fitting is indeed suppose to shut off the water when the expansion tank is un-screwed. I personally have tossed them when they have found their way into my hands and have used a threaded ball valve instead. I also did not trust it would hold.

FranklinD

Good 'nuff for me. After looking through dozens upon dozens of system pictures on this forum, I can't find any good reason to NOT remote mount it, as long as the connection is pointing up.

The ball valve I bought also has a drain cap, so I will put that on the tank side of the valve for easy pressure relief when I want to check the air charge.

Thanks!

Andy

Charlie from wmass

They do work, mostly. Better than being drenched in water.

4Johnpipe

If you can keep the XP tank location at the air separator they work great. The fitting is supposed to stay on that connection and the tank gets unscrewed from the fitting though. It should not be removed with the tank.

hot_rod

Those service checks can work as well as any seldom used valve, junky water will ball up any type of valve.

I think hanging tanks no their side with loop hangers or adequate perforated tape allows changing a tank, even a waterlogged on much easier. I have seen multiple tanks mounted on their side on a trapeze strut rack.

From what I read tell Amtrol approves side mounting Extrol tanks, in their guidebook.

This Engineering Guide is now available as a PDF. Shared with permission.
Pages of excellent reading on expansion and compression tanks, piping, sizing, etc.

FranklinD

Thanks for all the great info.

I ended up mounting the tank a few feet off to the side of the boiler on a wall bracket, vertically, with a Watts ball valve (with drain cap on the tank side so that I can check the air charge annually). Water quality isn't an issue here (I know everyone says that, but after exhaustive testing and research, it's really not a problem) so I'm not too worried about the valve gumming up. If it does then I have much bigger issues to worry about.

The main issue I had is that the tank was 4" from the top of the boiler, preventing canopy removal, and 2.5" from the stainless flue. Part of the sticker was already shrivelling up from the heat. Also, the tank's placement was such that I couldn't turn the valve on one of the circ isolation flanges as the handle hit the tank. Previously I had to take the handle off and turn the stem with a wrench.

Most of it was just a lack of forward thinking on the part of the guy that installed the boiler. Oh well.

Thanks again!