Water Heater - temperature erratic

[Lynne Marie]

Terry:

I have a duplex that is 10-years old and has the original hot water heater. Lately, I've been noticing that the temperature of the water is very erratic. It starts off hot but in a few minutes goes to luke-warm and I have to keep turning it hotter and hotter until I'm out of hot water (about 10 min). It never goes completely cold but i can consistently seem to keep a temperature while showering. Some days I notice this more than others, so it's not even a consistent problem. Do you have any advice as to why this may be happening or what I can do?

Thanks,

Lynne Marie

[Plumber Jim]

How Long before the water goes from hot to warm? if its in a minute or two you might have a bad dip tube. assuming that if its left to heat up that it always starts off hot. it it starts off hot one time and just warm the next maybe your gas control valve is bad. If the heater is ten years old you may want to consider replacing it, It may not be worth working on it at this point. If you want to check the dip tube you need to remove the nipple on the cold side ( inlet ) of the water heater. you will either have a plastic tube connected to it or you have to stick your finger in the hole and pull it out. If you find no tube or its only a few inches long then you need a new one as it should be almost as tall as the heater itself.

[BigLou]

Lynne,

is it an electric or gas hot water heater ? if its electric i would make sure both heating elements are working

[Redwood]

Ten years old, if its the original water heater could put it into defective dip tube era. Check this link and see if your water heater manufacturer and serial # are listed. http://www.rustylayton.com/htmlxtra/diptube.html

If the dip tube is bad or missing it will cause dilution of the hot water by the cold water with exactly the symptoms you describe. Sadly at ten years old if the dip tube is the culprit you may just be better off replacing the water heater than repairing it.