hot water heater

[kevfish1]

Hot water heater is not heating like it use to. Ussually everyone could shower and now after 2 showers I am out of hot water. anything to try that might help??? or is heater going bad

[Macgyver55]

Make sure nobody turned the water temp control down.

How old is it, gas or electric, city or well water?

[pureinsanity]

Here is some info that might help diagnose your problem.

Heating water causes calcium carbonate to precipitate out and settle to the bottom of the water heater. Water that gets under this layer of sediment can turn to steam when the burners come on and cause popping and other noises. The build up of sediment can reduce the efficiency of your water heater and reduce the holding capacity.

Regular flushing of the water heater through the drain valve can help prevent sediment build up and other water heater problems. Sediment can reduce the efficiency of the water heater and get into re-circulating lines and cause problems with circulating pumps and check valves.

Anaerobic bacteria reacting with the magnesium anode forms hydrogen sulfide gas. This gas smells like rotten eggs. Hydrogen Peroxide can be used to get rid of the bacteria but it usually returns. Replacing the magnesium or aluminum anode rod with a zinc/aluminum alloy rod will often get rid of the problem.

Insufficient Hot Water or Hot Water Not Hot Enough

Check for a broken dip tube, wrong setting on a thermostat, a defective thermostat, burned out heating elements (electric), or a heavy build up of sediment. Check out our trouble shooting guides.

The dip tube is a long slender tube that fits down into the water heater inlet. The dip tube directs the incoming cold water down to the bottom of the tank. If the dip tube is broken, the incoming cold water can mix with the out going hot water and cause it to seem as though the water heater is running out of hot water.

Noisy Water Heater

Noise coming from gas water heaters can often be caused by the sediment build up in the bottom of the water heater. As the burners heat the bottom of the tank gas bubbles form under the sediment. The thumping and popping noises are created by the gas bubbles escaping from under the sediment. Sizzling noises can be caused by condensation dripping onto the hot burner.

When water is heated it expands. If the inlet to the water heater is not blocked by a check valve, pressure reducing valve, or other device, the increase in volume simply travels back into the water source. If the inlet is blocked, this increase in volume will cause an increase in pressure, sometimes to dangerous levels. The T&P valve should relieve this pressure by discharging some water. A thermal expansion tank can be installed in the water line that will absorb the increase in volume preventing the relief valve from discharging water unnecessarily.

The hammering and pounding noise and associated vibration that occurs when a column of moving water within a piping system is suddenly stopped by a valve is known as "water hammer". When water is traveling in the pipes it has kinetic energy (energy of motion). When a valve shuts off suddenly a shock wave results. Not only is an annoying noise created, but damage to the plumbing system can occur. Water hammer most often occurs when a valve shuts off suddenly as with solenoid valves. Commercial water hammer arrestors are available to combat this problem. They consist of a small air bladder within a cylinder plumbed to the piping system near the valve causing the problem. They cushion the moving column of water. Some hardware stores carry them. Sometimes if the water piping is sagging then supporting the pipe solves the problem.

Condensation often occurs on water heaters when a large hot water draw occurs and thus a large amount of cold water enters the water heater. This condensation is sometimes mistaken for a leak in the water heater storage tank.

Scalding Dangers

Length of time for hot water to cause scalding

* 125 F 1 1/2 to 2 minutes

* 130 F About 30 seconds

* 135 F About 10 seconds

* 140 F Less than 5 seconds

* 145 F Less than 3 seconds

* 150 F About 1 1/2 seconds

* 155 F About 1 second

[BobT]

If it's an electric heater your symptoms indicate your lower heating element is defective. You get rather fast recovery but a low supply of hot water so it sounds like your top heater is the only one functioning. This is a common thing with electric water heaters because sediment collects on the bottom and eventually covers the lower element. The heater elements rely on the water to dissipate the heat but when they are covered with sediment, heat transfer is reduced and the heaters overheat and burn out.

A simple resistance check of the lower unit will verify this. Disconnect the power to the water heater (open the circuit breaker). Disconnect one of the wires from the lower heater element. Use a meter to measure the resistance between the two screws on the heating element. If it is open, the resistance will be infinite (maxed out on an analog meter). If you measure a resistance then the heater is probably ok.

If your element is ok then I'd start suspecting the thermostat for that element.

[Tom7227]

Generally two people can fit into a shower together and it is quite efficient and sometimes quite a bit of fun. Give it a try!

[BoxMN]

Not to hijack the thread, but if a hot water heater (electric off peak, 120 gallon, used on weekends mainly) is about 3 years old, should I use the bottom drain to drain some off to try to get rid of some sediment? I know if you wait to long it is better to leave it, just not sure how "long" that is. It is on well water behind a WaterBoss, and we do occassionaly smell the rotten egg. Thanks.

[BobT]

I think if you check your owner's manual you'll find that this should be done a few times a year. It can help but tank design is poor. Sediment still gathers and they don't make an access big enough to clean it out. That little 1-1/4" hole for the heating element doesn't give much room for cleaning. There's no reason they can make a 4" square or round opening to all someone to get their arm inside to clean it. Maybe I should design it and put it on the market for sale.

The rotten egg smell is usually hydrogen-sulfide gas. If it becomes a problem it can be removed from the water with a little plumbing. I had it so strong that you couldn't walk into or near our bath/laundry room without gagging.

I ended up putting in a bladderless pressure tank. This type of tank exposes the water to air, which allows the gas to evaporate out of the water. The result was immediate and we haven't had the problem since. I do refresh the tank about once or twice a year. I didn't have to remove the bladder tank I already had. I just added the bladderless tank to the system downstream of the bladder tank and then continued to the water softener (Water Boss) and the rest of the house.

[MARINERMAGNUM]

My brother has that smell too-like someone s#!t in the sink.

Is the bladderless tank like the old style galvanized? Does it require a vent for the gasses?

[kevfish1]

It is a gas water heater with city water

[Surface Tension]

Its the teenagers.taking longer showers

Check your flame to see if it is burning correctly. Blue flame,

Check the burner control temps setting.

Take the temp of the water after is has recovered.

[BobT]

Yes, the bladderless tank is the typical galvanized tanks. I bought a tank from Fleet Farm that is epoxy lined on the inside to resist rust and has been working out well.

The attached drawing shows how my system is set up. Note: the only reason I have two tanks is because I added the bladderless tank after I installed the smaller one and I didn’t want to just throw it out so I left it in the system.

On the top of the bladderless tank I added a valve so I could bleed off the stale air and then refresh the tank with new air a couple times a year. I also installed a drain valve on the outlet from the bladderless tank so I can hook up a hose and drain it into my floor drain. I just open the top valve until I get water then close it, turn off the well pump, and then open the bottom valve to drain the tank. As the tank is draining and after the pressure drops, I open the valve on top so fresh air will be drawn into the tank as the water drains out. When it’s done draining I just close the valves and turn the water back on. The air that is trapped inside will pressurize as the pump builds up the system pressure.

Now the hydrogen-sulfide gas can evaporate out of the water and into the trapped air in the tank. For some reason, the trapped air does not take on the odor from the gas. I can’t explain that but it does work. A friend of mine worked for a well driller and he told me how to do this. All I know is it works well.

[pikechaser]

Another thing to check with your water heater.. Make sure you dont have cold water bleeding over into the hot side, from a faulty faucet. Shut off the water going into the hot water heater..or going out if you happen to have a valve on that side..you want to make sure you have no flow thru the water heater. Go around to all your faucets, turn them on to hot only..you may get a little dribble at first..but you should not have water flow on the hot side with the water heater supply turned off. Single handle faucets are pretty notorious for this sort of thing.

[jwhjr]

Good timing on this thread. Our water heater (40 gallon gas/city water) was on its last legs after 16.5 yrs so I replaced it last night with a 50 gallon one. We have a family of 6 and the combination of everyone showering in the morning and the old one going out it just couldn't keep up any more. The 50 gallon should suit us well. It was bigger so I had to do a little rerouting of the pipes, but all in all it wasn't a bad job at all. A few pics of the new one installed (shut-offs on both hot/cold side came in handy to fix a small leak on the dielectric unions that needed a bit more thread tape):

[Redlantern]

Nice job! You can never have too many valves. I like the fact that you installed ball valves, they are at the same height and there is no solder splattered all over the top of the water heater.

[Pinusbanksiana]

What diameter copper lines did you use for the gas?

[jwhjr]

Not sure on the diameter for the copper gas line as it was existing (3/8" if I had to guess as it looks slightly smaller than my 1/2" water lines). I agree on the ball valves as the way to go because the other style aren't as reliable. The spin type that was on the cold side of the old water heater was so corroded I couldn't get it to shut off at all, even with a wrench. I also replaced the shut-off coming from the main with a ball valve. The one that was on there wouldn't shut off all the way. Luckily there was a ball valve style shut-off on the street side of the meter.

[Redlantern]

I'm guessing that the gas line is 3/8th i.d. (nominal). Now if you are buying flare fittings, they are sold by the o.d. size of the pipe. Also, do NOT use type M soft copper. The M refers to wall thickness. Minimum for gas lines is type L.

[RumRiverRat]

If the water is already hot why are you heating it?