Water heater troubleshooting and maintenanceby Jeff Cousins
We're often asked for help by folks who have trouble with their water heater. Forum staffer Jeff Cousins put together this troubleshooting and maintenance guide.
TROUBLESHOOTINGNo Hot Water At Faucets but Tank is Hot
You may or may not have a water heater bypass, but if you do, then it may be in the bypass position. Most RVs have one, two, or three valves that need to be switched for the bypass; check your RVs manual or call their technical support.
You can also get this symptom if the shower water taps are on and the water flow shut off at the nozzle/head. Remember you probably have an outside shower too. Cold water will flow across the valves into the hot side when you open another tap elsewhere, displacing the hot water you are expecting to get. Close the shower valves and the problem disappears.Propane Burner Noisy
An improperly tuned air mixing gate can cause excessive noise. That's the opening in the gas pipe just before it enters the burner tube that sucks in air to mix with the propane. Insufficient air can cause a weak yellow flame and may also cause some soot to form around the exhaust area. Too much air will cause excessive roaring.You might start by closing the mixing gate until the flame is yellow and gradually open it until the flame is blue with a yellow tip.. There is usually a screw that is loosened and a slide over the opening that can be moved.Atwood Hot Water Problems
Try watching this movie at the Atwood website.Propane Will Not Light
If propane has been shut off for storage it can take ages for air in the LP line to bleed out through the tiny pilot burner - just have patience (and maybe a pad for your finger on the pilot valve, if it is spring loaded). Lighting the stove and fridge first helps get the gas flowing.
Mud Daubers, spiders, or other insets can block the propane jet. Make sure it (and the exhaust) are clear.
If you do not hear the igniter on electronically lit water heaters check ALL connections for tightness and/or corrosion.Hot Water Odor
There is a bacteria that sometimes thrives in hot water tanks that smells like rotten eggs (sulphur); Odds are that is what you have. Antifreeze in the tank is not a problem, though it will smell like antifreeze. In any case, flush the water system thoroughly and sanitize with a strong chlorine solution. We have sanitizing instructions in the forum Library (see Library in the link bar above the messages).Leaking Pressure Relief Valve
If your pressure relief valve is constantly leaking water some models are available at local hardware stores while others including some Atwood models are a different thread type and have to be obtained from an RV parts source.
If the valve is located near the top of the tank (most are) and is leaking water you have lost the head of air that should be present. To replace the air cool the heater, remove the drain plug to drain the water, and then replace the drain plug and refill the tank. As the water fills the heater the air will be compressed in the top of the tank.Hot Water Tap Flow Very Slow
All of my faucets in my motorhome have a screen just below the faucet assembly. About once a year the hot water faucet in the bathroom and faucet in the shower in the bathroom slow noticeably. I simply turn OFF the water supply, remove the faucet handle and then remove the faucet assembly. If I look into the hole where the assembly was, I can see a very fine screen which is pressed into the bottom of the hole. I take an ice pick and gently pry the screen out of the hole (the screen is shaped with a upward bevel along the sides--kind of like a flat-bottomed U with much shorter sides). Use the ice pick on the sides and not the screening surface. After removing the screen, I use a towel to cover the hole and very briefly hit the pump switch. The brief water flow flushes out any sediment which falls away from the screen back into the pipe. I clean and replace the screen and faucet assembly and am good for another year. The screen can be pressed back into place with your finger.
This has always solved my problem. I don't know whether your faucets are of the same design but it doesn't take much time to disassemble a hot water faucet and look for a fine screen pressed into the bottom of the hole. Be careful not to tighten the faucet assembly to tight. Mine are plastic and it doesn't take much to break something. O-rings make the seal and over-tighting is not necessary. I you don't find the screen as describe above, inspect the faucet assembly to see whether it is plugged with white sediment from the hot water tank.
Alternate Solution is if your problem is mineral deposits (probably), introduce at least one bottle (20oz) of plain vinegar into the HWH, top off with water, and get it hot. Then remove the filters/strainers from the offending HW faucets and run until you get some of the vinegar solution coming out, then shut the faucets and let stand for 30 minutes or more. Afterwards, turn on the faucets and flush thoroughly to get rid of all the crud. You'll also have to drain and flush the hoot water heater - possibly several times. It'll be a messy task, but should get the job done. Also, I'd recommend you stay away from products like LimeAway. They contain phosphoric acid which, while great for grout, plays hell with brass and copper fittings.
WATER HEATER PREVENTIVE MAINTENANCE
Water heater should be drained on a regular basis (Every six months during heavy use and annually for weekend trips.) Shut off heater and insure that the water is cool by waiting or running water through it until cold. Carefully remove drain plug, allow water to drain, and flush tank with fresh water. (RV parts suppliers sell a small 90 degree nozzle that helps flushing lime out of the heater) They also sell spare teflon drain plugs which will be very handy when you twist off one that is seated too well! It can be removed using a hacksaw blade to split the threaded portion of the plug which can then easily be removed with needle nose pliers.
If large amounts of lime (white gunk) are present filling the water heater with at least one bottle (20 oz) of vinegar, topping off the tank, turning the heater on, and allowing it to sit for at least 30 minutes will dissolve the lime. If your water heaters drain is not on the bottom of the tank fill the tank up to the drain with vinegar , install plug and run water through the closest hot water faucet until tank is full and water starts flowing. After allowing vinegar to dissolve the lime drain tank, allow heater to cool, flush again and then run water through closest faucet until clear. You may plug up the diffuser on the faucet that will have to be removed and flushed.
Atwood doesn't require an anode rod but Suburban does. The reason Atwood doesnt is due to the material used in the tank. If anode is present check condition of anode and replace if necessary.