Installed new water heater today. No problems,

You have to replace water heater.
But you can buy-time if leak is small by turning heater off except when you need hot water. This will give you 30-60 days to shop and find best heater.
http://waterheatertimer.org/Leaking-water-heater.html
http://waterheatertimer.org/How-to-install-gas-water-heater.html

To prevent tank from rusting in this manner, inspect and replace anode rod each 2-4 years, and keep water pressure below 80psi.
http://waterheatertimer.org/How-to-maintain-water-heater.html

If you need further help, I’m available over the phone at https://www.6ya.com/expert/gene_9f0ef4df2f9897e7

You're probably in for a service call and/or possibly water heater replacement if unit is more that 5-6 years old.
Your water heater plugs into outlet. Check outlet with cheap circuit analyzer to make sure the unit is receiving correct polarity without line interference.
If unit is in the attic, then add more venting to soffit and roof so pilot is not being snuffed out by hot air. If unit is in basement, then open some doors and a window and see if unit needs more air.
Most gas water heaters require yearly cleaning and service.
Clean the combustion parts and tubes.
Clean the air intake.
Have gas company check gas pressure.
Open following link for possible illustrations:
http://waterheatertimer.org/How-to-install-gas-water-heater.html#troubleshoot

The problem can be bad gas control valve, air in gas line, low gas pressure, gas shut off handle not fully parallel with gas line, dirty combustion parts, lack of combustion air, improper venting. Or combination of all things. It's an electronic gizmo, anything can be bad or shorted, and repair may not last long.

Without a trained service technician to ohm-test the parts using correct service manual, then we are guessing at the cause.

Power vent water heater implies that you have side wall venting which must be replaced with another side-wall vented unit -or- it implies rapid reheating of water.

If water heater is more than 6 years old, you might be money ahead by installing a new one from local box store. Avoid the power vent and electronics. Local box store will have passive roof-venting type water heater BUT box store does not sell side-wall power vent. If your power vent goes up through the roof, then box-store variety gas water heater will work. Total cost $350 do-it-yourself for 40 gallon gas.
Or get 40 gallon 240Volt electric for $220 and connect to circuit breaker box. Requires no venting, and is easy to repair for years to come.
Or small 120Volt electric that plugs into outlet to tide you over until gas repairs can be made.
Look for scratch-n-dent models and always offer 10% off.
http://waterheatertimer.org/How-to-install-gas-water-heater.html
Shower uses 5-9 gallons hot water.

Hello, Your 20 year old water heater is nearing the end of it's useful life. Most water heaters last only 20 years before they start to leak. The reason most likely it has intermittent heat spurts is most likely due to two things, 1. The unit has a lot of rust in the water (you don't normally notice it during a shower) If you were to bleed off the rust by attaching a hose or bucket to the bottom of the heater's water outlet, and /or the over pressure tube located off of the top of the unit that has a copper pipe on it pointing toward the ground, that you would see a lot of rust come out of it. You could do this and get a bit more life out of it and better heat to boot, unless it decides to leak.
2. The water heater has a bad electric heating element (if it's electric that is). Replacing it may solve the problem but most likely the heater still isn't going to last too much longer anyways, so that would be a judgement call on your side.
You would in all likely-hood be better off replacing the entire water heater now while it is in a controlled environment before it leaks at some unfortunate time causing water damage and other damage at the same time when you are not around to control it.
Good Luck! Rich L.

My water heater has three water connections on the top of it one has a C for cold is that a inlet or outlet ? IT'S THE COLD INLET. The other spot has a H for hot is that a inlet or outlet ? IT'S THE HOT OUTLET. And the other one is not marked what is that one for and is it a inlet or outlet ? please email me at [email protected]. The last one is a pressure release valve that lets off excessive pressure when the temperature goes too high in the unit. When you install the heater, it should be installed into the drain pan that existed before or into a new one. You should also install a drain pipe from the valve to that drain pan, or into the drainage system for the house. This may depend on the codes where you live. Also install a good quality shut off valve on the inlet side for emergencies. A Ball type is good. Hope this helps,
Best Mark
I'm new to this site, so I'm not sure if I can email you directly or not. I believe not. Good Luck.

If you'r really lucky you may find a leaking fitting on top of the water heater thats draining down inside the shell and out the bottom, otherwise its time to replace a rusted out water heater.
Sorry

My unit is 3 1.2 tears old. It started to delay the flowing of hot water. Today I held the lever down until hot water came out but I noticed water leaking from inside the unit. I figured that the tank failed, and since it was over 3 years old I decided to open it up. What I found was that there is a plastic tube at the top of the unit that was very discolored and brittle which developed a crack. when I touched it it completely severed. I called the Insinkerator hotline at 1800-558-5700 and they told me that opening the unit voids the warranty. I said that it appears to be out of warranty and I needed just the plastic tube for repair. The per on on the phone said that as a one time courtesy that a new unit would be shipped to me free of charge and that I could install it myself or they will have a tech do it. I opted to do it myself. Hope this helps

It could just be a leak around the threads of the connection of the pipe nipple in the hot water outlet. If so, you'll have to take out the one there now and replace it with a new one.

Every part has been replaced by new units except the tank and the water do not heat up the water. The water is hot 3 inches on the bottom and three hour later the water is still cold on the top of the tank.
The ingnitor is still lite and the flame is still going but I dont get hot water. The Gas Company assured me of no leaks and ever part was in place. Whats the problem?

I had the exact same problem. I even replaced the first unit with a second unit...because I was sure I hooked everything up correctly. Then I called their support line and and felt very stupid. They asked one question "are you plugging in the Quick&Hot into the same electrical outlet as the garbage disposal"?. I said yes..and the garbage disposal works fine (thinking that this indicates a good electrical outlet). She then said "That outlet works off of a switch so no electricity is getting to the Quick&Hot until the disposal is turned on). Gosh darn it...that made total sense. I then tested this out by plugging an extension cord into a different outlet and it worked fine. Boy...do I feel stupid. Hope this helps.

try this, set the bottom therostat if it is electric , 10 degrees hoter than the top is set , if gas have no ideas