Why is there no hot water in the master bath?

[sepefrio]

I got a call back by a previous client today. Seems no one else would help them except to say "call a plumber" and have a nice day. They seemed at wits end, and I remembered them as a nice couple. I was close with free time so I agreed to come by and take a look see.

Anyways, here is what I found. Single story ranch style house. If you were outside facing the front door, the water heater is in the back left corner and the master bath is in the front right corner. The hall bath is about 20ft to the left (closer to the water heater) than the master bath.

The problem. No hot water in the master bath. There is however, plenty of hot water in the guest bath and kitchen. But, if you first run hot water in the hall bath, then there is somewhat hot water in the master bath. So, by itself, the master bath has only roughly room temperature water (not hot and not cold). But if primed via the hall bath, the sink has hot water and the shower has luke warm water.

All supply piping is copper and what cold be seen, it was not excessive. The master bath has a two handle faucet sink, and a single handle shower. The water heater is a 50gl 2001 model that looks to be operating just fine. Just prior to the sale, the master bath had been remodeled. It was originally a handicapped equipped house. The shower is a stall type that you could roll a wheelchair into.

During my first inspection, I did the hall bath first. So when I got to the master bath the sink had hot water. But I did notice the shower was barely warm at best. I went back to double check the water heater. Next to the water heater is the electrical panel. Thats when I heard the panel buzzing, and got temperatures of about 110 degrees on the breakers. (yes this is the same house where the panel blew me on my butt at a later date). It was decided by the owner to secure the power. So now the water heater had no power (All power was secure prior to the inspection too, so the water heater had been on maybe 20 minutes total). At the re-inspection the panel blew up, so we never got to follow up on the hot water issue. I told them to make sure and run the hot water at closing to see if it was OK. I never heard a thing so I assumed it was OK or being taken care of. That is until this phone call.

Anyways, I was stumped by this whole thing and the wife was frazzled. The husband called one plumbing company, explained the problem and they said they could come out and look. It would be $90 just to show up and then they suggested either the master bath would have to be re-plumbed or the water heater replaced. They further suggested the water heater may be too far from the bath.

I didn't like those answers and I liked these people so I asked them to give me some time to see what I could dig up. Well luck was on my side, I got a hold of a plumber buddy of mine and described the situation. He nailed it on the head after he got all the information (same as above). Well he thought about it for several minutes then it was like a "You know what, I just bet it's.........."

I had never heard of this situation causing this problem. I felt I should share it so maybe it helps someone else as well. But before I tell, lets see what the guess are.

Why was there no hot water in the master bath?

[hausdok]

Improperly adjusted mixing valve at the shower.

ONE TEAM - ONE FIGHT!!!

Mike

[Richard Moore]

Either that or sediment (or solder) clogging the hot water line at the mixing valve cartridge. With the water heater that far away and very little hot water exiting at the shower it would take a long time for any heated water to reach it. "Priming" the nearby guest bath makes the hot available that much sooner. I suspect he could have achieved the same by running the hot faucet at the master bath sink first.

Adjust and/or flush the lines and mixing valve. (If possible. I believe some cartridges may need to be replaced if they're badly gunked up.)

[sepefrio]

Originally posted by Richard Moore

"Priming" the nearby guest bath makes the hot available that much sooner. I suspect he could have achieved the same by running the hot faucet at the master bath sink first.

Ahh, but the master bath sink ALSO did not have hot water until primed by the hall bath.

BTW, this is what really confused me. I could understand how one or the other would not work, but both?

But anyways, Mike was right in there. The handle in the shower was actually installed improperly. When I called the home owner and told him what it might be, he took the shower handle off. With the handle off, the handle itself would rotate from the 12 o'clock to the 6 o'clock position. Previously when installed, it stopped at the 3 o'clock position. He said one of the plastic "washers" was in backwards. He flipped it around, the handle rotated just fine when installed again and now both the sink and shower have nice hot water.

To be honest, I still don't understand how this problem would cause the sink to not have hot water. I guess it is plumbed to the shower then feeds the sink so it passes that mixing valve.

Anyways, I learned something and the client is extremely pleased. So a win win situation for all involved (except their agent who they first asked for help but was to busy to bother).

[Erby]

He's frigging got us playing Columbo!

I hate Columbo!

Given Mike took my first guess, I'd go with a cross connection somewhere.

[Richard Moore]

"Ahh, but the master bath sink ALSO did not have hot water until primed by the hall bath."

Then, I guess I'm still confused why the "priming" in the guest bathroom would make any difference to the way things worked in the master, other than the timing of the hot water eventually arriving. Odd!

[msteger]

You say the master bath has a sink and shower. I assume the hot water at all fixtures in the master bathroom were opened for a few minutes?

Is the water pressure similar on the hot side compared to the cold side? Obviously, if there was little to no pressure on the hot side of the sink and shower, I'd say a valve was closed. If you're getting no hot water and full pressure on the hot side, but 'room temp' (not cold) on the hot side of the sink and shower, I'd be a little puzzled. If it was only the shower, I'd guess a faulty mixing valve at the shower control, but it seems to also be the sink so I don't know. I'd say a plumber is the next logical move to figure out what's going on.

[fqp25]

Could be some kind of cross connection in the hall bath.

Frank

[Tom Raymond]

He said it was a handicap bath, some crafty plumber decided to save a few bucks by using the anti-scald mixing valve on the shower to temper the sink. Then he failed to read the directions and botched the washers on the shower valve.

Tom

[fqp25]

Alright John, times up. What did he say?

Frank

[sepefrio]

Originally posted by fqp25

Alright John, times up. What did he say?

Frank

LOL, I said it up above. On my buddies advice about the mixer valve, the owner removed the handle, found the washer installed backwards (thus the handle would only turn half way). He flipped the washer back around, the handle completely turns now and plenty of hot water everywhere.

So it was a washer in backwards on the shower handle. Repair time about 15 minutes, cost $0.