very little hot water

[pa bell]

Our Suburban water heater (SW6del) is putting out less and less hot water. There is good flow at the spigot. The water is real hot at first but can not even get through a quick shower with hot water. Just reading this forum and others it doesn't sound like the check valve. Help me keep the Mrs. happy, what could it be?

 

[donn]

Do you have an outside shower?  If so be sure the valves are closed.

 

[Rene T]

Is it just the hot water side? When you turn on the hot water faucet, is the flow much less than the cold water faucet?  Is the cold water flowing good? Need answers to these 3 questions before we go any further. 

 

[pa bell]

The outside spigots are shut off. The flow from the hot or cold spigots are the same, both strong. The problem is only for the hot water.

 

[Rene T]

The outside spigots are shut off. The flow from the hot or cold spigots are the same, both strong. The problem is only for the hot water.

When you say outside spigots, I assume you mean the valves for the outside shower.
Can you tell us how many valves you have for bypassing the water heater when winterizing?
If you only have one, you need to check it to make sure that it is shut. Now it may appear to be shut but it may be partially open and allowing cold water to get into the hot water side of the hot water outlet cooling the hot water.

 

[pa bell]

The RV is a toyhauler so the outside spigot is just for a hose not a shower. Either way, the spigots are shut off. There are a hot and cold bypass valves on the back of the heater. Hot water then tees off to the bathroom and kitchen.

 

[Rene T]

The RV is a toyhauler so the outside spigot is just for a hose not a shower. Either way, the spigots are shut off. There are a hot and cold bypass valves on the back of the heater. Hot water then tees off to the bathroom and kitchen.

Can you take a picture of the piping on the back of the heater?

 

[Gizmo100]

Just a long shot...
Are you sure both the gas and the electric heaters are working? Namely the gas part pf the water heater. 

 

[pa bell]

Just getting back to this post. Life is busy being retired as a Florida winter clogger.

I did not mention before as I didn't think it pertained to the problem but when I go to the electric side of the  hot water it gets too hot and comes out the pressure relief valve. (for a few bucks a month I just stuck with LP). I did try switching to electric and taking a shower and did not make a difference in the problem of too little hat water.
I was not able to post a picture as the forum rejected it. Any how, there is an input and output with a bypass pipe. The valves are set for direct input and output direct to house plumbing. Bypass inactive.

 

[donn]

OK.  Turn off the WH.  Turn off the water.  Open the pressure relief, then remove the anode.  Drain the tank. Replace the anode.  Turn the water back on.  Run a hot faucet until no more air.  Turn the WH back on.  Let it heat up.  BTW dripping from the T&P valve is totally normal.  How long does it last?

 

[pa bell]

Donn, I will do that flush procedure tomorrow. The relief valve wasn't dripping, it was gushing out. A hot shower lasts less than 5 minutes.

 

[donn]

While your at it go to the hardware store and buy a brand new T&P valve.  There is nothing special about the one you have.  I suspect you may have lost your air head in the tank.  Or possibly its simply full of crud.  When was the last time you replaced the sacrifical anode rod?  If you get a lot of crud out with the water, spend the time and flush the tank.

 

[old_toys]

I had the same symptoms of hot water going cooler last year. it started off hot and went south from there.
it was all my fault, my water heater has a shut off valve between the input and output of the water heater lines and I had the valve open. closed the valve and was back to normal. found I need a check list.