Rheem 40 Gallon FVR NATGAS Low WATER HEATER 6YR 22V40SF - Page 7 - Answered Questions & Fixed issues

U cannot put it back together it is a fail safe if the unit over heats from a plugged inlet the spring loaded damper is released by one of two way solder retainer melts or vial melts either way the the unit is bad contact Rheem with the 1800 number on the tank and depending on the age they will replace the tank. You will have to uninstall it take it back then install the new tank all not covered by them or if you can't do this a local plumber or hvac company can do it for u

The self igniter, or thermal couple is bad.

at the bottom of your tank where the removeable plate (access) is, remove it, look inside and you'll see the thermocouple could be bad.. also see if the tank is lit, if it is, then it's a good bet that the thermocouple is out... it is real easy to remove

Relief (pop-off) valves can be replaced. Make sure to get the right one. They unscrew from the unit. They are generally screwed in very tight, you may have to get a good size wrench or pipe wrench to loosen it; especially if it is more than a few years old.

Your heater is in need of maintenance by a qualified technician.

Don't try to fix it yourself as gas(?) can be dangerous if the air/gas ratio is wrong (i.e. explosion!).

Turn off your heater and do not use it until it has been repaired!

Might need to install/ replace the pressure reducing valve between the house and water supply.

If this heater was manufactured after 2003 it has a FVIR filter. It is usually located on the bottom of the heater and this is where it draws air into the combustion chamber. Check to see if it is clogged with dust or lint.
because the heater probably has a sensor, it is not getting enough air and shutting off. hope this helped.

tank looks to be leaking and getting the insualtion and floor wet .. so replace water heater?? Once the tank is leaking there is no repairing it..

Your temp and pressure valve is leaking, one of two problems is causing this. Either you need to install/ replace the pressure reducing valve between your house and the city water main(well), or you need to check the thermostat to be sure it is not overheating. Whatever you do DO NOT plug, cap, or block the t&p valve ever. Doing this is a bad idea, and could be fatal.

leaking tank, probably rusted at weld. replacement is the only sure cure.

sounds like one of the saftey relays might be going bad. or the ingniter might be cracked or need cleaning

Check thermostat, check power is on,

Remove the burner access cover under the control valve. Press the pilot light button (gas control) and hold it down. At the same time, light the pilot. Continue to hold the lighting button for a few seconds until the thermocouple heats up. Release the button. Twist the gas control knob to the ON position, and the burner should fire up after a few seconds. Replace the access cover. Good luck.

There are heat sync balls in the nipples of your cold and hot water lines on your hot water tank. Cut the water lines and remove these balls as sometimes they come loose and float to the point where your water line connections to the tank are causing the pressure to drop when your tap is turned on

Your gas valve may be faulty and need replacing as it is not sensing the change in water temperature in your hot water tank,

unfortunately it does not. All natural air drafted hot water tanks have an AFUE rating of only 80%

change the thermcouple

"Pres sw open" means there is insufficient air flow. either the vent if blocked, or the blower turns too slow/ or died.

As long as the tank is not leaking. Go to Rheems website, and look up your model.
As with any large home appliance I would recommend a plumber or HVAC professional licensed by your state to perform the repairs.
I am pretty sure the part you need will be the gas valve contoller.
Please elt me know what you find.

You may have a plugged orifice in the pilot tube assy. If you have any way of getting to the orifice with compressed air, and blow back, it may dislodge it, if it is plugged. If possible, carefully remove pilot tube at valve end first, so that if it is debris in there, it blows clean of the tube, so it won't clog again. Otherwise you'll have to remove complete assy. Another thing to try as well, is to shut valve off, loosen fitting at valve for pilot tube, AND MAKING SURE NO FLAME OR SPARK ANYWHERE IN THE AREA, take a spray bottle with dish soap and water mixed (bubble tester) and then spray at pilot fitting when it is loose, and push pilot, to see if any bubbles appear, indicating gas flow. If no flow there, then I'd get a new gas valve.