Attwood 6 Gal Heats but no water flow

[1966Florida]

Hello all I have an Attwood gas hot water heater with electronic ignition model G6A-8E in my airstream. The unit fires up quick. I get 120 degree hot water in the tank but I get very little hot water flowing out of bath sink or kitchen sink. Pipe throughout trailer is new pex. All valves have been upgraded. I flushed hot water heater with 50% vinegar solution. turned on hot water heater for 15 minutes then Rinsed tank thoroughly with garden hose- Still not getting hotwater to steadily flow. I get a slight warm water out of tap then cold again. I tried the shut off valves in various positions (see Picture) Still no hot water flowing???? Any suggestions?

[Drathaar]

Seems to me that your valves are correct. Do you get good flow when you're in the bypass mode?

[HowieE]

Your valves are set right.

Do you get full flow from the cold water side? If not remove the strainers at the faucet an clean them. Retry hot.

If you have full flow at the cold side and not at the hot side try opening the bypass, center, valve and test. If you have flow while the bypass is open I would assume the heater tank has a clog at one of the taps and restricting the flow in or out of the tank. Not likely but that is what the test would indicate.

If you did not have flow while the bypass valve was open I would remove and check that each of the feed valves is in fact open. The handle indicates they are but stranger things have happened.

[ericpeltier]

I had the same issue. I pulled apart the pex and found this.

[HowieE]

What is that? That is much bigger than any pex I have ever seen.

[Larry C]

If that's PX, it's the biggest diameter I've ever seen. Where did it come from?

Larry

Originally Posted by ericpeltier

I had the same issue. I pulled apart the pex and found this.

[1966Florida]

By " By Pass Valve" I assuem you mean the valve in he middle in the picture? What exactly is the purpose of this valve? I have tried it both ways- open and closed- still no solid flow of hot water through faucit- only sproratic burst of hot water.

[HowieE]

Well in looking again at your picture you have another problem.

Yes the center valve is the bypass valve. It is used to winterize and allows water to flow through the system while the heater is isolated. Now for that word "isolated". In order for that to work the other 2 valves have to cut off the water to and from the heater. If the input and output of the heater are at the top just off the picture, as I suspect they are, your valves are in the wrong placement for things to work. They have to be after the bypass valve not before it. Someone plumbed it wrong.

Send another picture that displays the complete back of the heater, both inputs, to confirm this.

[HiJoeSilver]

Where'd you get those valves, having a hard time finding pex valves with those kinds of hand wheels.
Do you get good cold water flow from the fixtures, just no hot . Rules out clogged aerators.
Where does that pipe top left that disappears go to?
Looks like 2 lines in front on the floor , are they one hot one cold?

[TG Twinkie]

The cold water line should enter the bottom of the water heater. Hot out the top. I will assume the cold is on the left and the hot is on the right in your pic. The cold water comes in on the upper left. The hot goes out and down on the right side. If so, the cold valve is positioned correctly. But I believe the hot valve is in the wrong position.
Do you get any water out of the hot water side of things? Cold, warm or hot? Is it just poor flow/pressure?
Do you have a low point drain open on the hot water side?
How about the cold water low point drain?
Are you on the pump or city water?
Sounds to me like the water heater is not full.

Does the handle on those valves fit in only on position?
We need a better pic showing more of the upper piping.


Sent from my iPod touch using Airstream Forums

[1966Florida]

Thanks for all of the input on this- I still have not resolved this hot water flow issue? These valves are all new I placed the new valves in the exact same spot as the old factory airstream valves. They are 1/2 turn style valves and I purchased them at either Home Depot or Furgeson Plumming Supply 8 months ago. I tested everything after changing out old leaky valves and the hot water was working fine. Now the trailer has sat for 8 months and I have this problem. Here is a recap of the symptoms:

1. From both kitchen sink and bath sink I get good water flow out hot and cold side.
2. I get small spurts of hot water/warm coming through the faucet when running facet in full "Hot" mode when water heater is on.
3. I have attemped this test on city water and on fresh tank water- still no constant hot water flow.
4. I thoroughly flushed the hot water tank with a 50% vinegar water solution and then inserted a small hose attached to the garden hose and flushed it out thoroughly. I Did Not see lots of milky corrosion come out.
5. The gas igniter is firing appropriately and the water inside the tank is warming to 120 degrees- Its just not flowing.

I took another photo from a different angle through the rear storage compartment. photo 2 is a photo that I googled of a similar atwood heater showing the valve placements.

[HowieE]

The picture on the right is correct. You will note the shutoff valves for winterizing are between the bypass valve and the heater. That is how the heater is isolated and can be drained during winterizing.

I still can not see the inputs on your heater so I can't say it is right or wrong, but I still suspect it is wrong.

Please either post a picture that shows the inputs tot he heater or give a description of the piping that defines which pipes go to which input on the heater. Top pipe will be hot out and bottom pipe will be cold in.

[TheHandyDan]

I'm not seeing the inlet and outlet to your WH in your photo but if you look at the Attwood photo you can see how the bypass is supposed to be plumbed.

Cold water goes through the blue pipe into the heater and out through the red pipe. The bypass is enabled by closing the valve going into the heater and the valve coming out - and then opening the valve between the blue and red lines.

On your photo it's not clear if your bypass is in the right place because I can't see the inlet and outlet to the heater.

Can you confirm that the bypass is in the right place? If so, does the water flow properly when you bypass the heater? If that's the case, the issue is inside the heater or one of the valves.

[1966Florida]

Ok I crawled back in through the storage hatch and shot this photo- the left side of the photo has to be the "inlet" and outet of the water heater/top and bottom since there are no other pex lines going into the heater tank.

[TheHandyDan]

If your inlet and outlet are at the top of the photo then your bypass valve is on the wrong side.

It needs to be before the inlet valve and after the outlet valve.

Right now water is flowing into the heater and through the bypass valve to the hot side. So it's not bypassing anything.

Closing the bypass valve will make water go through the heater, but you still don't know what's causing the blockage.

[1966Florida]

PROBLEM SOLVED- THANKS GENTLEMAN!!
I cut all of those valves in the clear and started from scratch. Rebuild the inlet and outlet from the tank itself- works great. - ALmost bit the bullet and spent $375.00 on a new hot water heater.- Could not have solved this w/o your help!!!