water heater with broken dip tube

zepfan

what is a sign that when a 50 gallon gas water heater has a broken dip tube, how long normally does it take to run out of hot water? Is it instantly, after 5 minutes, or shorter? thanks to all.

Jamie Hall

A 50 gallon gas or oil heater should be able to run a couple of baths full of nice hot water without any trouble at all.

hot_rod

take a 5 gallon bucket into your tub or shower, see how many gallons before it runs luke warm.

How many minutes of hot water depends on the faucet. Big high flow tub fillers can drain 50 gallons in 5 minutes or so.

A typical 2.5 gpm shower head should give you 15- 20 minutes depending on how hot you have the tank set.

Paul48

With a broken dip tube, you will get lukewarm water, at best. The water takes the path of least resistance.

ChrisJ

From my experiences, a broken dip tube will be hot, but it will cool off long before it should, and end up running cool to cold much sooner.

With my 50 gallon gas heater I can easily take a hot 40 minute shower followed by the wife having her usual shower, no issues. I run the heater around 140F.

In an apartment we had, it had a 40 gallon heater, yes it was smaller, but I couldn't get more than one 15 minute shower out of it, and I had it cranked up to 150-160F. After 15 minutes we were talking luke warm at best and it ended up cold fast. As soon as you felt the temperature drop it meant you needed to get the soap off you ASAP.

I'm pretty sure the heater in the apartment needed a dip tube as we had the same symptoms from an AO Smith heater at my parents house in the 90s that had a dip tube issue.

delta T

Keep in mind too, that not all broken dip tubes are the same. It could have a small crack in it, or it could be completely broken off, I have seen both and everything in between. If it snapped off, then You will likely only get luke warm water at best. If it is a small hole or crack, you may very well get a decent shower, just not quite as much as you should. Only way to be sure is to remove it, and that process can range from easy to practically impossible......

Henry

From my own personal experience, you get hot, then cool and then cold is short order. Both inlet and outlet are less than a foot apart. Water goes where it is easieer. I fixed mine and a number using copper pipe. Don't forget to drill an 1/8 hole near the top. Tha is an old fashioned vacuum breaker.

ChrisJ

Henry said:

From my own personal experience, you get hot, then cool and then cold is short order. Both inlet and outlet are less than a foot apart. Water goes where it is easieer. I fixed mine and a number using copper pipe. Don't forget to drill an 1/8 hole near the top. Tha is an old fashioned vacuum breaker.

But..........it's inside the tank?

Henry

Mine, I pulled out with longnos. Used a vicegip to hold it while I cut 3 feet off its lenght. Then I just pulled t out. Another one it was reachable and it was probably lying on its side in the tank.

ChrisJ

Henry said:

Mine, I pulled out with longnos. Used a vicegip to hold it while I cut 3 feet off its lenght. Then I just pulled t out. Another one it was reachable and it was probably lying on its side in the tank.

I mean your old fashioned vacuum breaker.
It's inside the tank?

Seems like all that hole would do is help in bleeding air out of the tank when it's first filled, but after that, nothing?

rick in Alaska

The hole used to be in case the pipe in the house had a break in it that started siphoning off water, it would only allow the tank to drain down until it got to the level of the hole in the dip tube. Kind of effective as a vacuum breaker.
Also, if the dip tube was broken off, it could give all kinds of different amounts of hot water usage, depending on how far down it was broken off. The only way to tell for sure is to pull it out and check it.
Rick

EBEBRATT-Ed

@ChrisJ said "With my 50 gallon gas heater I can easily take a hot 40 minute shower"

40 minute shower????

really

hot_rod

EBEBRATT-Ed said:

@ChrisJ said "With my 50 gallon gas heater I can easily take a hot 40 minute shower"

40 minute shower????

really

40 minutes at 2.5 gpm sounds a little long?

Need to know
tank temperature
shower temperature
incoming cold temperature
burner size of the tank
to get a number using math

I've heard numbers like 87% of the tank capacity of 120° is available for a shower so for a 50 gallon tank 43 gallons or minutes at 1 gpm flow

bob eck

Did you have a new single handle faucet installed in the house lately?
Some times with single handle faucets you can get a cross connection letting cold water into the hot water lines.
get a laser didital temp gun turn on the shower faucet and let it run and put it on the hot water outlet pipe see if the water temp goes down or if the temp stays up and the shower water still runs cold. If this happens you have a cross connection.