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bill14jr.
Nov 15, 2010, 01:00 PM
Idiot who installed safety valve did not allow for its replacement ( inadequate clearances )without having to disassemble a large portion of manifold. Can a new valve be added to the output port of existing one to save considerable cost? I know this is probably very unconventional, but money is tight. Thanks in advance.

massplumber2008
Nov 15, 2010, 01:03 PM
Bill...

Don't mess with this valve in any way except the right way, OK? This valve saves lives and plumbing codes are very specific about NOT messing with it or its discharge... no joke - no exceptions!

In most cases, the pipe coming out of the relief valve can be cut and the pipe removed as it is only used to direct a discharge to the floor safely. To remove the relief valve you should be able to isolate the system, depressurize the system, drain some water and then remove/replace the relief valve.

Fill the system, purge the system and then install the pipe with the male end into the relief valve and use a 3/4" sharkbite coupling to reattach the cut pipe.

Does this sound reasonable or did I miss something?

Mark

bill14jr.
Nov 15, 2010, 01:37 PM
Thanks, Mark. I know about the discharge side of the valve, and it is certainly doable. My problem is in removing the valve; it must be turned out of the female fitting. The installer evidently put it on before he attached the rest of the piping, and there is not enough clearance to remove the valve when backing it out. So I guess I'll just have to spend lots of money to get it off, and have the piping done correctly.

massplumber2008
Nov 15, 2010, 04:31 PM
If the piping can flex abit... I'd try to turn the valve out.

Only other alternative could be to plug off this relief valve and install a new relief valve off another tapping at the boiler... ;) You MUST install another relief valve if you cap this or someone could get hurt, OK?

Something to think about anyway!

Mark

bill14jr.
Nov 16, 2010, 07:00 AM
My luck there is absolutely no flexibleness with the cast iron fittings. The problem is upon turning the valve out a half turn the top of the valve ( trip handle ) will contact the top of the boiler cover, which is not removable. I fully realize these valves are safety items, but in a pinch, why wouldn't a second valve in series work? If the first valve blows open, wouldn't the second open also, or would there be too much delay? Even so, couldn't the first be jammed open via the trip lever? I won't do that, but in theory, wouldn't that work? Thanks again, Mark, for your interest in this subject! Bill

massplumber2008
Nov 16, 2010, 02:47 PM
Hi Bill...

No, adding another valve is series won't work as each relief valve has an internal sensor (spring mechanism) that will not be immersed/exposed in the heating unit and therefore will not sense the correct temperature /pressure and would not react when it needed to... that make sense?

The fact is that if you mess with this valve and someone gets killed you can be sure that no insurance company on the planet will insure you... ;)

And not to be dramatic, but people have really died messing around with these valves like you are suggesting!

I'm all about being creative and if I thought there was some way to help you I would in a heart beat! However, the simple fact is that you can't get creative here... gotta bite the bullet... no getting around it.

Like I said in my last post, you can plug this valve off and install a new relief valve at another tapping... probably best bet here!

Mark

bill14jr.
Nov 17, 2010, 08:05 AM
Thanks, again, Mark. Your explanation makes sense, and I'll heed your good guidance. You are truly one of the good guys! God bless.
Bill

speedball1
Nov 17, 2010, 08:17 AM
Did we ever determine why Bill needs to replace his T&P valve?
Just wondering, Tom

bill14jr.
Nov 17, 2010, 09:15 AM
Sorry I did not say initially. The valve occasionally weeps ( half a cup or so ), and I've read that manually tripping it may make it worse. Unit is 8 years old, pressure never goes above 22 PSI and temperature never above 200 degrees. Those values seem to be the norm for my particular boiler which is common in our housing development.

massplumber2008
Nov 17, 2010, 09:47 AM
I figured that, Bill, But Tom's right, I probably should have asked... :)

Mark