Hot water heater question

Tom S.

you guys are the smartest people I know so here's a question I'm posting for a non-computer literate friend.

He has a standalone gas hot water tank, 30 gallons (I think, might be 40). It is relatively old, 10 years. He says that they get hot water for maybe 1/2 a shower and then it goes luke warm at best. It then takes an hour to get hot water back again. They do not have a fancy high-flow showerhead, so I doubt they are depleting the supply that quickly.

Is this explained in an easy way by the age of the tank?

Thanks for any thoughts,

Tom

Mitch_4

check the

dip tube. Standard tanks have a tube that drops the cold water to the bottom of the tank, this activates the stat, and puts the cold incoming water at the bottom near the burner.

Over time the tube can split, or even simply disolve if it was part of a problem the tube manufacturer had in early in 2000, but affected tanks as old as 1995. Sometimes they break right at the inlet.

The quickest test is to turn on a hot water tap full bore. The burner should light off in 2 minutes if the tube is ok. (max is 3 IMO) Put a thermometer inthe water stream, you will the temp start to fall as the cold water mixes. In essence when the water does not reach the bottom of the tank first, it basically cools the entire tank before the stat responds.

Mitch

Jim Erhardt_3

This could also be due to an accumulation of sediment on the bottom of the tank, decreasing heat transfer from combustion. This is why many water heater manufacturers recommend flushing the tank once a year using the drain valve at the bottom of the tank.

BTW, not meaning to nit-pick but it's not a "hot water heater" - simply "water heater." If the water is already hot you wouldn't need to heat it, would you?

Tom S.

good point on the water heater vs. hot water heater. Hopefully this is not as offensive as boiler/furnace!

Thanks to both of you for good suggestions, I will pass them on to my friend.

Tom

Randy Schuyler_2

I lean toward a broken dip tube, too. Generally, sediment buildup doesn't affect hot-water output much, although it does other unfortunate things to water heaters. And 10 years old might put it in the range of the Great Dip Tube Debacle.

Randy Schuyler

Tom S.

Replace or repair?

If it is the dip tube, is it worth replacing or at 10 years old should he be looking for a new water tank?

Thanks again,

Tom

Randy Schuyler_2

Replacing a dip tube is simpler than replacing the water heater! You'd turn off the water pressure, unhook the cold plumbing, and take out the nipple. Then, using variously a long handle of channelock pliers, a dowel, your pinkie, or anything else similar, you'd work the old dip tube up and out with a stirring motion.

Factory dip tubes are usually flared at the top and sit on a steel ring. You can either get another one of those, or one that has an integral plastic-lined nipple.

At 10 years, though, it's also time someone checked the sacrificial anode. If more than six inches of core wire is exposed, it should be replaced.

Randy Schuyler