Apollo EXV Valve at Hot Water Heater Cold Supply

[ktornquist]

Hi,

I am hoping you all can help me understand a bit more about the valve that I have upstream of the hot water heater along the cold water supply line. It is a shut-off valve, but has a barb with polytube connected (goes to floor drain) that I am not familiar with. I assume it is some kind of pressure release? Anyways, I changed the tubing out today as it was fairly molded up. It looks like there is a constant stream coming from this barb. Is that the correct operation? It seems like a waste to me.

Thanks!

 

[Reach4]

It is what you suspected -- a pressure release. It should not have water coming out all of the time.

Apollo 78RV SERIES
http://www.apollovalves.com/products/114

See the "IOM" document... says you can clean the seat. There are repair kits too.


If you got a thermal expansion tank, you would not need that pressure release.

 

[Sponsor]

 

[Jadnashua]

If you have a closed system, when your WH runs, the action of heating the water causes it to expand. Your pipes are generally not able to balloon up to accommodate that expansion, and the pressure will rise quite dramatically. So, water will then leak out at the weakest point. A relief valve is an engineered 'leak'. Not a good thing in most cases. The correct thing is, as was said, an expansion tank to absorb that expansion, and then feed it back into the pipes when you later open up a valve.

If you have a pressure reduction valve (PRV) or the utility has installed a check valve, then you have a closed system. Water can come in, but can't expand back out.

 

[ktornquist]

Reach/Jim,

Thank you for the info. The house is fairly new (built end of 2015) so I can only assume it was built to code. From the information you've provided, it sounds like you would either have an expansion tank or one of these thermal expansion valves. A few questions:

- From my observation today, it seems to dripping/flowing at all times. Is the proper operation that this valve is to release water only when the hot water heater is running?
- Where would I find the PRV? Would this be near my whole house water shut-off? My understanding is that I could reduce the pressure at this valve?
- It looks like my option right now is to clean the seat of the valve to see if that helps, if not then I need to buy a repair kit. There are threads on this control valve. How do you judge exactly how far that valve should be tightened?

Again, I appreciate all of your help. I apologize for the "dumb" questions in advanced.

 

[Reach4]

From my observation today, it seems to dripping/flowing at all times. Is the proper operation that this valve is to release water only when the hot water heater is running?

Yes, pretty much. The heater is heating, and there is not even a little water being used in the house.

Where would I find the PRV? Would this be near my whole house water shut-off? My understanding is that I could reduce the pressure at this valve?

Could be there. Step 1 is to get a water pressure gauge. These are widely available with a garden hose thread. You can attach that to a laundry tap or to the drain for the WH. Outside faucets may read higher than inside because sometimes those are piped to the water before the PRV.

If the water pressure in the house is very high, over 90 or 100, even if the WH is not heating, then that Apollo valve may be doing its job. Then you would seek out the cause.

If the pressure is under 90, then look to the Apollo valve.

It looks like my option right now is to clean the seat of the valve to see if that helps, if not then I need to buy a repair kit. There are threads on this control valve. How do you judge exactly how far that valve should be tightened?

Take pictures. You will soon know more about that than we do.

 

[ktornquist]

So this morning, I shut-off the valve and pulled the control valve. The seat didn't look dirty, but I wiped it all own and placed it back in. It looks like it is still dribbling when the hot water heater isn't heating. I will go the route of the pressure gauge to see what is running in the house. As for how far to screw the control valve down, it was seated all the way until it cannot be tightened anymore. That is how I put it back.

I did take it upon myself to go ahead and do the yearly hot water tank draining while doing this so not a complete loss.

 

[ktornquist]

Alright, dumb question, I found this document on Ferguson, which lists different part numbers for the Apollo repair kits. Which kit would I select?
https://api.ferguson.com/dar-step-service/Query?USE_TYPE=INSTALLATION&PRODUCT_ID=4272680

 

[Reach4]

I am guessing w3017h100 or w3017h125 because your output is a barbed fitting. That would make sense if the repair kit is the whole sidecar piece including the barb.

What is your water pressure???? That gauge is easy to find.

Can you turn that round part coming out of the end? I expect that is how you get to the seat to clean it.

 

[ktornquist]

Quick update, the water coming into the house was only about 65 psi. I switched out the expansion valve portion of the entire valve and it is working now like it should. Sounds like long term solution would an expansion tank or replacing this every several years.

 

[Reach4]

Quick update, the water coming into the house was only about 65 psi. I switched out the expansion valve portion of the entire valve and it is working now like it should. Sounds like long term solution would an expansion tank or replacing this every several years.

1. What part number did you order?
2. Would you show us a photo of the piece that you swapped out?