Tip & How-To about Heating & Cooling

What to do if Hot Water from the Water heater Is Too Hot


If steam or excessively hot water shoots out of faucets, or you hear boiling sounds inside the hot water heater, the appliance may not be shutting off at its set temperature.
The job of the temperature-pressure (TP) relief valve is to release excessive pressure from steam buildup, but this valve may have been improperly installed, or it may be faulty. Either way, this condition can be dangerous, both because hot water and steam can scald people and because the water heater could rupture.
Here’s what to do:
1) Turn down the water heater’s temperature.
2) Allow the water to cool.
3) Replace the water heater's pressure relief valve.
4) Turn the water heater's temperature back to normal and wait about an hour. If the problem occurs again, call a water heater repairperson.

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explain why there is spluttering sound when water is sprinkled on hot oil


Hello. When water is sprinkled on hot oil will sputter because the oil is at a temperature near or over 100 degrees C or 212 degrees F. This is the temperature where water boils. The sputtering that you hear is the water being boiled and creating steam. When the water boils and becomes steam, it expands extremely fast. This creates a "bubble" in the oil and the bubble "popping" makes the sputtering sound.

Dec 29, 2010 | Heating & Cooling

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turned off the hot water to fix a leaking tap. now the tap has no hot or cold water and the hot water tank valve is leaking?


It sounds like two problems.
Problem 1) Clog inside faucet or clog inside pipes at faucet
Remove supply tubes leading to faucet and see if problem is inside pipes or inside faucet.
My bet is clog inside faucet.

If you have galvanized pipe that meets copper pipe, this can be trouble spot.
Article on clogged water pipes at Inspectapedia:
http://www.inspectapedia.com/water/Water_Pipe_Clog_Repair_Guide.htm

Article on clogged pipes:
http://www.waterheaterrescue.com/pages/WHRpages/English/Troubleshooting/Tanklets/backflushing.html

Problem 2) Water heater leak ... you say tank valve is leaking? Is that cold-water shut-off valve? Or tank drain valve? Or TP valve?

If cold water shut-off is leaking, then replace shut off.

If tank drain valve is leaking, then check if plastic valve is cracked. If drain valve is cracked, then replace with a brass valve from Home Depot. If plastic valve breaks off, then use hammer and screwdriver to gently chip out the broken plastic valve. New valve threads need teflon tape to seal pipe. If valve is just dripping, then put garden-hose cap over end of valve and screw down tight.

If TP valve is leaking, then replace with same temperature and pressure rating.
New TP valve threads need teflon tape to seal pipe.

Problem 3) If pressure is low all over house:
Buy pressure gauge at hardware store that screws onto hose connection.

Test pressure on outdoor spigot.
Open faucet and check if pressure drops. This says if problem is inside pipes that enter house.

Test pressure on water heater drain valve.
This says if pressure problem is before -or- after water heater.

If problem is before the water heater, then shut-off valve located on cold water line is suspect.
If problem is after water heater, it could be in hot water outflow pipe on top of water heater, or a nearby elbow.

Remove hot water line leading from water heater and check pressure. This says if problem is where hot water leaves tank.
Read articles above about clogs inside water lines.


Nov 16, 2010 | Rheem Water Heater Pressure Relief Valve

1 Answer

water from new water heater smells like sulfur & has air pockets


Sounds like there might be a super-hot spot in the water heater and the water is boiling. Can you hear some percolating noises from within the water heater from time to time?

Mar 12, 2009 | RELIANCE ELECTRIC WATER HEATER

1 Answer

Bradford White Water Heater Model: M165R6DS13


Immediately turn off power to heater. One of two things has happened. Either: A. The electrical contacts in one of the thermostats has welded together, necessitating replacement of the thermostat(s). (in this case I would recommend replacing both upper and lower thermos) or B. The lower element has burnt through, and because there is 120 volts to the lower element at all times (it normally only heats when the thermos complete the circuit to give it a path to the other "hot", putting a full 240 volts on it) a section of the element will continue to heat up to the point where the break allows the current to complete it's path to neutral ground via the water in the tank. It can continue to heat until the high limit safety thermo trips out. (the red reset button on the upper thermostat)
If either condition exists, the high limit safety thermo should trip out power to the heater before boiling water, and thus steam, is produced. Even if the safety thermo should fail to cut power, the pressure / temperature relief valve should open, releasing excessive pressure. If that should also fail to open, due to corrosion or such, the water heater will create steam and can actually result in explosion, and possible injury or death!
Several years ago I came across one that was boiling and when I turned on a hot water faucet to relieve the pressure it filled the entire basement with steam. (I still shutter to think if I didn't catch that fast enough I or someone else could have been killed)

The most likely cause of your extra hot water is actually the lower element. After you turn off power to the heater, turn off the water supply to the heater, open a hot water faucet to allow air to enter the tank and drain the tank. Remove the lower element. A bad element is usually visually apparent. If it looks good, you would have to test it with an ohm meter. (should be about 20 ohms if it is good) Install new element, turn on water and fill until water flows steadily from the hot water faucet you left open. Now you can turn the faucet off and turn power back on to heater.

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Water Heater Repair


If steam or excessively hot water shoots out of faucets, or you hear boilding sounds inside the hot water heater, the appliance may not be shutting off at its set temperature. The job of the temperature- pressure (TP) relief valve is to release excessive pressure from steam buildup, but this valve may have been improperly installed, or it may be faulty. Either way, this condition can be dangerous, both because hot water and steam can scald people and because enough pressure could build up to rupture the water heater. Immediately turn down the water heater’s temperature setting and allow the water to cool.

Aug 27, 2008 | Emerson Part UWL Chrome Ultrasystem water...

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