expansion tank questions

[JK60]

There are some screws and the tape is added as an extra sealant.

 

[Cass]

Thats fine. Enjoy Christmas

 

[Sponsor]

 

[Gary Swart]

Sure seems to me that there a heck of a lot of discussion over something that is really a very elementary problem with a very simple solution! This is now a closed system and the PRV is performing exactly as it is supposed to do when 150 psi is reached. This is what expansion tanks are design for, and one will fix the problem. End of story!

 

[Cass]

Sure seems to me that there a heck of a lot of discussion over something that is really a very elementary problem with a very simple solution! This is now a closed system and the PRV is performing exactly as it is supposed to do when 150 psi is reached. This is what expansion tanks are design for, and one will fix the problem. End of story!

Do you mean the T&P?

 

[Gary Swart]

Oops! Yes, that's what I meant.

 

[damfino]

Thanks for the advice and links. My plumber is on the right track now and is researching when the county switched to the new check valves to make sure there are no issues with other houses he's done recently. As strange as it may sound it is a new problem for this area. I called Ferguson today and they have just recently started stocking them in the north beach area so I'm thinking they put the new valves in first. A lot of the houses in our system don't even have check valves much less dual checks.

 

[uncleal]

I have noticed a grunfos recirculation pump on the hot water line, in the picture. Is the recirculation through the cold line? Unplug this pump and test the hot water heating again. The recirculation tee at the far end of the house my also be faulty.

 

[JK60]

I have noticed a grunfos recirculation pump on the hot water line, in the picture. Is the recirculation through the cold line? Unplug this pump and test the hot water heating again. The recirculation tee at the far end of the house my also be faulty.

I have provided the picture as a reference to the thread originator - damfino. The Grundfos recirculation pump is on my hot water system which is trouble free. Yes the recirculation is through the cold line.

 

[Toolaholic]

THANK'S JK 60 for the photo

that may help a homeowner figure things out.

GUYS it wasn't a bullseye for the pistol range give him a break

 

[vaplumber]

Here is what you do, I don't understand why you are not following the logic given here.

You need a high pressure PRV < Pressure Reducing Valve, you are dealing with pressure that might be spiking from use from other establishments in the area.

Install the PRV after the dual check valve. Install a 4 gallon expansion tank between the shutoff on the cold water inlet and the top of the tank. Jog that tee perpendicular to the pipe entering the tank, turn up a 90 and then a 3/4 FIP to allow better support of the tank. If you have PEX running straight into the tank you will have to hard pipe at least a foot out of the tank to get stability for the tank, reconnect to PEX. They make all the connections to do this. Set your pressure of the expansion tank to the working pressure you set the PRV at, Watts dictates this procedure on their website and the paperwork that comes with the tank.

*** Do not remove the dual check, it is required for a reason***

You are flirting with disaster with the high pressure you are dealing with. The only reason I am mentioning the high pressure PRV is because they are only $35 more than the regular ones and your range can accept surges a great deal better. It's worth the money.

If you have your water heater temp set up higher than 120 degrees this may definitely cause the high pressure along with the absence of an expansion tank.

DO IT NOW, YOU ARE ENDANGERING YOUR LIFE

I agree completely with all of this! I have witnessed first hand how an older water heater with a thinning tank can blow out under similar pressures. One locally even made the tv news when it blew, taking out a utility room, an exterior wall, a ceiling under a second story bath, and the life of two adults who were asleep in a bedroom adjoining the utility room! This does not sound real, but it is! Use an expansion tank, a pressure regulator, and a pressure relief valve.