Hello,
Here’s my situation:
- I turn on the hot water at the kitchen sink. I get warm water for about 15 seconds, then it goes cold.
- I checked the water heater, it is putting out hot water.
- The only thing I can think of is that cold water is somehow getting pulled from somewhere else in the system and cooling it off.
a few other facts:
- location is in a (currently unheated cabin where it is dropping down to the 20’s at night and up to the 40’s during the day.
- recently roughed in the shower control in bathroom, but it is not yet hooked up [could this be causing hot/cold recirculation?]
I’m puzzled. any ideas???
Regards,
Mr. SQL
Replies
Some plumbers cross connect during rough in to conduct their pressure test. You didn't happen to do that, did you?
Are you sure the water heater is doing its job. Do you have another faucet that is getting hot water, continuously, from the hot water tap?
Is your water heater gas or electric? If electric, then maybe only the upper element is functioning, although 15 seconds of hot water seems a little low.
Water normally enters a tank via a dip tube which extends to the bottom of the tank, or on real old models you'll sometimes find the actual supply entry at the bottom of the tank. It's possible that the tube - plastic in most cases - is shot and the incoming water now mixes with the hot right at the top of the tank. This could account for the 15 seconds of warm and then the cold as the mixing of the two will quickly negate the hot.
Pop that sucker out and see what's what.
What type WH, storage or tankless?
Storage
Do you have a pressure reduceing valve in the system?
not that I'm aware of
What type valve at the sink where the problem occurs?
regular faucet. It happens at all the sinks (kitchen, bathrooms).
If your roughed-in shower faucet is on, or partially on, you could get cross-mixing there. Make sure it's shut off just to eliminate that possible source.
>>>location is in a
>>>location is in a (currently unheated cabin where it is dropping down to the 20's at night and up to the 40's during the day.
Is this a single-lever faucet in the kitchen? With the temps being well below freezing it might be possible that you've got some ice damage inside your faucet cartridge. Does the temperature inside the cabin fall below freezing?
If you've installed the shower control, and it's a single-handle unit, and the shutoff valves to it are open, that's likely the problem. It may be that you just need to install the control handle and (in the process) turn the cartridge around the right way, or it may be that the cartridge is defective or not installed correctly.
Of course, if this is in a cabin where the temps dip below freezing at night you have bigger problems than just some cool tap water.
Hi Mr. SQL
I'll bet that you have this problem only in the winter and that's the hint to figure it out.
Your water pipes run near the heat duct under the sink and that warms a small section of pipe, just enough to make you think you have a problem.
Chris
Yep, we had that problem in our house, until I wedged foam between the cold water pipe and the duct.