Price Pfister Shower Issue

[Cavalier]

The pipes all "merge" together because of the black insulation so we cannot tell where they are going or hooking together.

The supply comes through the wall from the crawl space and travels up beside the water heater. At the top of the heater it splits into the softener and water heater. From the heater the hot supply travels back into the crawl space. I do not see anything where the cold and hot supply are connected after the split by the heater.

 

[FullySprinklered]

Dip tube?

 

[Sponsor]

 

[Cavalier]

Dip tube?

Interesting. I'm not too familiar with this. Is it possible this could be defective where it works for all supplies except one shower supply?

I do have another question. On the 3/4 supply going to this side of the house I have 2 showers, 2 sinks and the washer. Does the flow rate through the supply pipe change when more sinks/ showers are turned on? I mean if I turned on the shower in question and could measure the flow rate through the supply line under the house does it remain the same when I turn on the sink? If the rate increases when the sink is turned on, it sounds like there might be some type of obstruction in this 3/4 supply that is overcome with an increased flow rate. Of course that doesn't explain why I turn on the hot water at the sink and the shower gets hotter while the sink never gets hot with the shower running.

 

[Jadnashua]

Do you have shutoff valves to the sink that causes the shower temp to change? If you do, shut them off and see what happens. If your shower then works fine, service or replace that faucet...it is creating the crossover from worn internals. If not, you could do the same thing all around the house to try to isolate the offending device. Keep in mind that the water will flow along the path of least resistance so blocking that off, things will return to their 'normal' path, and things should work fine. If that happens to be cold through the hot line, that's what will happen because that path has less resistance than hot moving through, but it starts with some problem that allows it to cross-over in the first place.

The symptom of a broken dip tube generally is that everywhere you're using hot water, it runs out quickly as the incoming cold to the WH then mixes with the hot water at the top of the tank verses being directed (dipped) into the bottom of the tank. Since the hot water is lighter in the tank, you can get more of that hot water out verses having it mixed with the incoming water at the top (pretty much all WH have the hot outlet at the top since that's where it accumulates).

 

[Cavalier]

Do you have shutoff valves to the sink that causes the shower temp to change? If you do, shut them off and see what happens. If your shower then works fine, service or replace that faucet...it is creating the crossover from worn internals. If not, you could do the same thing all around the house to try to isolate the offending device. Keep in mind that the water will flow along the path of least resistance so blocking that off, things will return to their 'normal' path, and things should work fine. If that happens to be cold through the hot line, that's what will happen because that path has less resistance than hot moving through, but it starts with some problem that allows it to cross-over in the first place.

The symptom of a broken dip tube generally is that everywhere you're using hot water, it runs out quickly as the incoming cold to the WH then mixes with the hot water at the top of the tank verses being directed (dipped) into the bottom of the tank. Since the hot water is lighter in the tank, you can get more of that hot water out verses having it mixed with the incoming water at the top (pretty much all WH have the hot outlet at the top since that's where it accumulates).

I think I understand. Are you saying a defective sink fixture could be the cross over? Would it matter if the sink fixture was a single or two handle? fixture? The reason why I ask if this could only happen with a single lever fixture, then the only culprit could be the shower fixture in the other bathroom. Since there are no shut offs for this I'm not sure how to test it. Probably just replace the cartridge.

 

[Jadnashua]

Yes, the only thing that can cause a cross-over in a faucet fixture (except when it is open) is a single handle device. Some notorious shower valves that can have that problem when worn are Symons, if I remember correctly, and then, only some models.

It really sounds like what you're experiencing is your shower is drawing cold water into the hot line from somewhere that limits its ability to get hot enough for comfort. Finding that offending device takes some detective work.

 

[Cavalier]

Yes, the only thing that can cause a cross-over in a faucet fixture (except when it is open) is a single handle device. Some notorious shower valves that can have that problem when worn are Symons, if I remember correctly, and then, only some models.

It really sounds like what you're experiencing is your shower is drawing cold water into the hot line from somewhere that limits its ability to get hot enough for comfort. Finding that offending device takes some detective work.

Since the only single lever fixtures I have are in the shower in question and the other shower, does that mean it's probably they other shower fixture?

 

[Jadnashua]

Probably. What brand and model is the valve?

Another potential cross-over is for the washing machine supply lines. Not normally an issue, but possibly depending on what you've done there. If you have shutoff valves to the WM, turn them off and see if it makes any difference. As was said early on, a hot water recirculation system can have that problem. If your piping is ideally routed, it can be done without a pump, but you'd be able to see some return line connected down low to the water heater, and it doesn't appear there is a line there, so probably not in your case.

If you have a two-handle valve with a hose connection on the outlet that has an individual shutoff, that can cause it as well. ANy place where the hot and cold are connected together is suspect. Even a two-handle shower valve if you have a shutoff at the showerhead and leave both valves normally open.

I have a hose that is connected to both hot and cold, and at the end of the hose is a typical nozzle that can be turned off. I use it to get warm/hot water to wash the car. While that's being used, there is the potential of the hot and cold mixing in the rest of the house, most noticeable when the nozzle is closed. I always shut the valves off when finished, so the cross-over is blocked.