RE: hot water heater

[wavemaker]

 
whats wrong with the heater when the water just runs out the overflow valve??
 Does it mean i have to buy a new one?
 
 Dean

[bikolee]

 wavemaker
Sounds like you need a new relief valve to me.

[tlhdoc]

 wavemaker
You may have too much water in the water heater.  There should be an air pocket at the top of the water heater.

[mike4947]

 wavemaker
Very common problem in caases where the water is left in the heater between trips. The air gets absorbed by water. The relief valve needs an air pocket to work correctly. A heater full of water creates pressure. If there s an air pocket it will compress without the air pocket the pressure overcome the relief valve.
 Solution: drain some or all the water. It does need to be drain occasionally just to get the gunk build up off the bottom which can build up to the point that it acts as an insulator and the heater doesn t function well.

[Dust64]

 wavemaker
Dean: Not to contradict Mike, but once a proper air " head space"  has been established within the hot water inner tank it will remain there throughout the camping season unless you drain the water tank. Each time you drain and refill the hot water tank you must reestablish the head space for proper operation of the relief valve.
 
 Why must there be air at the top of the tank?  This area allows for the pressure increase within the tank as the water is heated to remain below the 125/150psi threshold of the pressure relief valve.   Without this ability to allow for pressure increase during heating the relief valve would constantly drip water directly onto the main burner.   This in turn affects the fuel/air mix causing a reduction in air in the mix causing the burner to burn " rich"  producing a lazy main burner flame and excessive sooting.
 
 How do I properly establish a head space within the hot water heater? First and foremost the trailer must be level in order to properly perform this procedure. After draining and flushing the tank, close the drain valve or reinstall the anode rod. If de-winterizing the water heater leave the hot water bypass in the " bypass"  position. Connect the fresh water hose to the camper and open each hot & cold valve for the camper allowing the water to run until all antifreeze is flushed from the lines and the water runs clear.  Don t forget the outside shower valves. This will remove the antifreeze from the lines without allowing any of it to enter the hot water heater tank. Leaving the sink hot water valve open, open the hot water heater bypass allowing the water heater tank to fill. Let the tank fill until the water exiting the open hot water valve runs clear and without any air sputter. Leave the hot water valve open and turn off the water supply. Now walk outside and open the pressure relief valve located on the front of the hot water heater. Allow this valve to drain excess water until it quits. Close the pressure relief valve and go back inside the camper and close the open hot water valve at the sink. You now have a proper air space within the hot water heater and it will remain there until you drain the tank next time. Keep in mind however, if you park the camper " off level"  you will change the level position of the water inside the tank and it is possible that it will " weep"  when heated. Another good reason to insure that you level your camper.
 
 Now if you follow the above procedures and the pressure relief valve continues to allow water to drip through you ve got a bad valve and it should be replaced as none of the components within the valve are field repairable. Real simple job to replace as the valve simply unscrews from the tank. ..earl

[mike4947]

 wavemaker
Sorry Earl, but the folks at Suburban is where I got my information. Air is soluable in water and will dissolve in it if left over a period of time. It s not quick, but they recommend draining at least twice a year to regain head space (they said the units are designed to get the head space by simplely filling, nothing fancy required) to flush sediment from the bottom of the tank, and inspect the anode rod.

[Dust64]

 wavemaker
Mike: Without you & I embarking into a " chemistry"  discussion, it s my understanding that the opposite is true. When left for a prolonged period of time the hydrogen and oxygen within the water molecules break down causing the distinct " rotten egg"  smell sometimes encountered when opening a hot water tap.
 
 As to my procedure for establishing the required air space within the hot water heater being considered " fancy" , I m merely stating the procedure as outlined in the Atwood Water Heater Training Manual, dtd September 2002, page 26, quoted as follows:
 
 STEP 1:  Turn off water heater.
 
 STEP 2:  Turn off incoming water supply
 
 STEP 3:  Open the closest hot water faucet in the coach.
 
 STEP 4:  Pull handle of pressure-temperature relief valve straight out and allow water to flow until it stops.
 
 STEP 5:  Allow pressure-temperature relief valve to snap shut, turn on water supply and close faucet.
 
 Even though I ve quoted the procedure directly from the Atwood Hot Water Heater Service Manual the same procedure applies to the Suburban models as it is the procedure taught at their service schools for the last 20 years that I ve attended them.
 
 Since the purpose of this forum is to share both personal experience as well as verifiable technical expertise I personally feel responsible to maybe delve a little too deep when replying to fairly simple posts. I feel that sometimes explaining how/why something works goes a long way in helping folks that might be a little less experienced/knowledgeable than you and I understand why it isn t working.
 
 Given my propensity for rambling I do however try to limit my technical responses to those times that I might be able to clairify responses given by others, such as yourself, that do such a great job, both here and on other boards. Please accept that my response to the original question was simply for clarification and not an attempt on my part to " shine" ...earl

[mike4947]

 wavemaker
Well both proceedures accomplish the same thing, letting air into the tank to reform the air space.
 As to rotten egg smell. You have to have sulfer involved, That rotten egg smell is hydrogen sulfide. Another good reason for a really good filter on the incoming water line and a good reason to dump the heater occasionally if you camp in areas that could have dissolved sulfer in the water supply.

[bikolee]

 wavemaker
Mike and Earl,
 I have NEVER heard anything before about an air pocket. I drain my tank after each trip. Before leaving on a new trip , I hook up to the hose, open the hot water faucet at the sink and once the air has escaped, turn everything off. I still say that if Dean has water coming out of the relief valve, then his relief valve is defective and needs to be replaced.

[tlhdoc]

 wavemaker
bikolee you may very well be right, but there is supposed to be an air pocket at the top of the water heater.[]

[jackgoesthepopup]

 wavemaker
Hay Guys .
 Let me put my 2 cents in . There is a air space in top of the Hot water heater. It is desigened into the tank. The water outlet side of the tank extends down from the top to give you that air pocket. This designed into the tank so you have a area for the water because as you heat the it will expand. Water will absorb air to a point if it sits for awhile. But remimber your presure relief valve is not just rated for preasure but also tempature. A relief valve works by a spring that will ofseat when the preasure in the tank over comes it. It s a good idea to lift the seat on the valve every now and then. This helps the spring from becoming weak from lack of use. If the valve is leaking buy there are only 4 things that can cause ths
 1. bad valve
 2. water temp to high.
 3. water preasure to high
 4. something got stuck in the seat of the valve.
 But this is all mute.a relief valve costs onlt 10 or 15 bucks. If you have a problem with it just replace it. The proper way to do this is to turn of the supply side of the tank. Drain the tank. This is neededto help get the sedament out of the tank and gif you the air pocket. While you are draining the tank remove and replace the valve. Once the tank has been drained . Refill the tank.  Nothing to it. And one more word of advice install a pipe form the valve to the outside of the trailer in case it ever blows teh water goes outside and not on the floor of teh camper.

[mike4947]

 wavemaker
Sorry Tim, but there is the 5th reason and it is no air packet, althought it is related to your #3. Without the air pocket to compress; the pressure inside the tank is raised and seeing as how without the air pocket, water is against the valve it WILL leak water.
 This has been a common problem for years on RV s that sit for extended periods without draining the hot water heaters. It s even seen on house water heaters if they are left unused for long periods of time.
 The first step is to drain the tank, refill and see if the valve still leaks. If so then replace the valve.

[wavemaker]

 wavemaker
ok,
 i finally got to check my hot water heater out... did what everyone says, and i still get the same thing...
 im going to go with bikolee,s idea and go to get a relief valve
 ill let ya know what happens