Expansion Tank Mounting -- can I use previous relief port?

[thumper300zx]

I have a ball supply valve with a low [edit: previous was wrong and read 125psi] pressure release. It seems over the last year or so it's been leaking off more and more water. There isn't a 'rebuilt' kit for the little release valve/spring assembly. It's been really cold outside and the discharge formed an icicle outside, clogging the drain and eventually it backed up all the way to the drain pan and spilled over a bit. Lucky for us, it was a bit warmer that same day and it melted the icicle just enough that I heard a 'woosh' and the water drain out. We ended up with a very small amount of water that made it to the lower floor ceiling, but have avoided an imminent catastrophe.

The ball valve is a WATTS valve with pressure relief, and it's soldered in. I think I would like to install an expansion tank instead. Was wondering, if I just remove the relief valve, can I adapt the expansion tank onto that port instead of cutting into the supply line (between valve and heat tank, of course)?

Thoughts? Someone else in our development had this same kind of thing happen. The plumber installed an expansion tank, and just capped off the old relief valve. As I said, I'm wondering instead if I could just adapt it onto the relief valve instead.

 

[frodo]

some one capped these pressure relief valves in these 2 homes

the t&p valve is telling you there is a problem by leaking, if you cap it, the pressure will build up instead of leaking out and your house will disappear. hopefully with out your family inside


remove and replace the t&P valve with the same psi as the one already installed

and never touch that handle..leave it alone or you will be buying another one

 

[voletl]

If you cap the relief valve you just created a bomb.
Remove the relief valve and put the expansion tank in the port you just created a bomb.

Seeing how your water heater is leaking out of the relief something is wrong and the fact that you wanted to plug the relief valve with an expansion tank my advice is to call a REAL plumber not the guy your neighbors used.

 

[thumper300zx]

If you cap the relief valve you just created a bomb.
Remove the relief valve and put the expansion tank in the port you just created a bomb.

Seeing how your water heater is leaking out of the relief something is wrong and the fact that you wanted to plug the relief valve with an expansion tank my advice is to call a REAL plumber not the guy your neighbors used.

I think maybe you're thinking I'm describing the main pressure release valve coming right off the heater. The valve I'm talking about is a different valve...I said above it was 125psi but I messed that up. It's something lower, I'm sure, up next to the a supply side ball valve.

I'm not going to cap it off and leave it that way. Either gonna replace it or cap it after adding an expansion tank. What I was wondering is if it would be ok to adapt an expansion tank into the barb where this low pressure expansion relief valve currently is (where the white drain tube is coming out).

 

[KULTULZ]

...hmmph...

Learn something everyday here...

-Combination Ball Valve and Relief Valves-

 

[thumper300zx]

Some have said these ball with relief valves aren't code anymore, but they are still sold in local plumbing shops. I'm definitely doing an expansion tank, but just wondered if it can work off that relief port. Because the potable expansion valves are all 3/4 thread (the port is 3/8), from what I've seen, I'm just going to go ahead and T it in and cap the llow pressure relief valve.

 

[Mr_David]

where does that white tube go?
You say that port is a relief?

valves like that are usually ported to install a pressure gauge.

To be a relief valve that port would have to have some type of mechanism in it.
I think it's just a port drilled into the valve.

pressure can pass through a 3/8 hole just a easy as a 3/4 hole.

The size matters more when dealing with volume.
so if you wanted to connect that to an expansion tank it will still work, just not in the proper way it was designed.

 

[KULTULZ]

Description:

Series BRV Combination Ball Valve and Relief Valves are used in commercial and residential applications on water heater installations. It consists of a bronze body construction with a full port (reduced port with PEX connection), nickel-plated brass ball, blowout-proof brass stem, PTFE seats, stem packing, and stem thrust bearing, Viton relief ball, stainless steel relief spring, brass adapter, and steel handle (the relief valve outlet includes a drain tube connection with PEX or compression fitting models). Series BRV has a low profile design and can be installed in any position. It is for applications that require a means to shut off the water supply to the water heater and for providing protection from excess water pressure caused by thermal expansion. Pressure Rated: 400psi. Relief Valve Pressure Settings: 75, 80, 100 or 125psi (5.2, 5.5, 6.9 or 8.6 bar).

WATTS- Refering URL In Above Post

 

[Deerslayer]

If that's a relief port then no I wouldn't put a tank there.

 

[Deerslayer]

I would swap that 90 out for a tee and put the tank on the vertical above the tee on a fem adapter.

 

[thumper300zx]

where does that white tube go?
You say that port is a relief?

valves like that are usually ported to install a pressure gauge.

To be a relief valve that port would have to have some type of mechanism in it.
I think it's just a port drilled into the valve.

pressure can pass through a 3/8 hole just a easy as a 3/4 hole.

The size matters more when dealing with volume.
so if you wanted to connect that to an expansion tank it will still work, just not in the proper way it was designed.

It had a spring and a small rubber ball (stopper). When the pressure exceeds the spring rate, it opens and allows water to pass. The white tube routes down to the pan drain hole, about 3 inches down the drain pipe.

See explanation above on the Watts valve. I've seen them in several plumbing stores and online. I'd feel ok about mounting the expansion tank on it, but I'd have to use at least two adapters to get from 3/8 to 3/4 and don't want to do that.

 

[thumper300zx]

I would swap that 90 out for a tee and put the tank on the vertical above the tee on a fem adapter.

I've read a couple people discourage upward vertical mount because air could get trapped. Is that just untrue? It seems horizontal would cause similar (though not as severe) situation (also read about bladder failure with horizontal) since near half the volume would be above center.

 

[Deerslayer]

I've read a couple people discourage upward vertical mount because air could get trapped. Is that just untrue? It seems horizontal would cause similar (though not as severe) situation since near half the volume would be above center.

Um, the whole purpose of the tank is to provide a cushion of air for the water to compress when pressure rises. IMHO vertical mounting is generally less stress on the pipe and my preference when it's possible.

 

[thumper300zx]

Um, the whole purpose of the tank is to provide a cushion of air for the water to compress when pressure rises. IMHO vertical mounting is generally less stress on the pipe and my preference when it's possible.

Certainly less stress. I like the idea of mounting at the elbow.

 

[KULTULZ]

I've read a couple people discourage upward vertical mount because air could get trapped. Is that just untrue? It seems horizontal would cause similar (though not as severe) situation (also read about bladder failure with horizontal) since near half the volume would be above center.

AMTROL newest models are recommended to be mounted in the downward position so as to eliminate trapped air collected in the water. You make your own decision as how to mount.

Personally, I would mount it with the fill pointed downwards as to hopefully not have water stagnate within it. It should be mounted above a ball valve for easier service and air pressure adjustments. It should also (IMO) be held by a mounting bracket to alleviate any weight pressure on the plumbing.

If one is concerned about air bubbles collecting in the water portion of the tank, a air vent valve can be installed in the circuit.

 

[Deerslayer]

AMTROL newest models are recommended to be mounted in the downward position so as to eliminate trapped air collected in the water. You make your own decision as how to mount.

Personally, I would mount it with the fill pointed downwards as to hopefully not have water stagnate within it. It should be mounted above a ball valve for easier service and air pressure adjustments. It should also (IMO) be held by a mounting bracket to alleviate any weight pressure on the plumbing.

If one is concerned about air bubbles collecting in the water portion of the tank, a air vent valve can be installed in the circuit.

Funny they show it on the left of the heater, must be looking from the backside but typically it would be on the right, always on cold feed.

 

[KULTULZ]

Funny they show it on the left of the heater, must be looking from the backside but typically it would be on the right, always on cold feed.

I've come across many illustrated this way. It can cause confusion...

 

[Mr_David]

I fixed it. Maybe it's from south of the equator or where they drive on the left side of the road.

 

[SHEPLMBR]

These valves act like the Old Govenor 80's That watts makes. In an area where you cannot fit a tank these valves are sometimes used to relieve pressure. Out here where I am at least that's what is the "norm.

http://www.apollovalves.com/products/by_product_specific/402

http://www.watts.com/pages/Product-Profile/Gov80M2/

But codes change district to district.

 

[KULTULZ]

The Governor™ 80M2 also has its predecessor’s unique surge release feature. If you suffer from banging or knocking water pipes, the built-in surge release protects your plumbing from costly pressure surges due to thermal expansion.

I wonder if and when excess pressure is released into the tank if it makes a pooting an/or gurgling sound?

YOU OK IN THERE? Need a doctor?