Dometic 320 water valve

[routemaster]

The water valve on our when slams shut causes the pipes to bang, water pressure is at 45psi tried a resistor still no joy. Any ideas?

[C_Schomer]

I have a two year old Dometic 320 and it works great. I have a 2 gallon bladder tank at the pump and ive foam wrapped and anchored all the waterlines that I can get to. I hear the 320 water valve thump when it closes but no line rattle whatsoever. There are much better hammer arrestors than that Oatey. I’ve used some that were scaled down bladder tanks, about the size of a pint jar that I bought from commercial plumbing suppliers. Craig

[TXiceman]

Cummins12V98 wrote:

TXiceman wrote:
We tried a Dometic 320 and it was a piece of junk. Took it out, returned to dealer and got the parts to repair my old Thetford.

Ken

Curious as to what about it made you think it was a "piece of junk" ???

With proper water pressure and flow it would not sweep the bowl and you had to use the hand sprayer. After I got online looking for a resolution, I found it had problems with the pedal breaking and leaks as well as very limited parts were available. Basically, it is a throw away item.

Ken

[routemaster]

ChuckSteed wrote:
If the water pressure is good (you are using a pressure regulator)... not a Camco piece of junk.... then replace the valve

And if you let that foot pedal snap up hard you WILL sooner or later crack the pedal mechanism and be buying a new toilet...

The pedal did break so I bought a 5/8" rod ABS spun it down to fit in the part glued it in.

[Cummins12V98]

TXiceman wrote:
We tried a Dometic 320 and it was a piece of junk. Took it out, returned to dealer and got the parts to repair my old Thetford.

Ken

Curious as to what about it made you think it was a "piece of junk" ???

[TXiceman]

We tried a Dometic 320 and it was a piece of junk. Took it out, returned to dealer and got the parts to repair my old Thetford.

Ken

[Cummins12V98]

Look up Wellxtrol WX-101 (140PR1), 2 Gal WELL-X-TROL In-Line Well Tank

You can get for under $100.

[routemaster]

Cummins12V98 wrote:

rhagfo wrote:

ChuckSteed wrote:
If the water pressure is good (you are using a pressure regulator)... not a Camco piece of junk.... then replace the valve

And if you let that foot pedal snap up hard you WILL sooner or later crack the pedal mechanism and be buying a new toilet...

I doubt that replacing the valve will have much effect. I close the valve slowly, but still get a bit of hammer.

The real issue is that there are no built in air chambers in an RVs plumbing. I would suggest, and will likely buy one of these Hammer Arrestor. Simply replace an elbow with a Tee and install the arrestor.

That is a cheap first try. If that does not work a small expansion thank should do the trick.

Are you talking about the tank like the one on the water pump?
Den.

[Cummins12V98]

rhagfo wrote:

ChuckSteed wrote:
If the water pressure is good (you are using a pressure regulator)... not a Camco piece of junk.... then replace the valve

And if you let that foot pedal snap up hard you WILL sooner or later crack the pedal mechanism and be buying a new toilet...

I doubt that replacing the valve will have much effect. I close the valve slowly, but still get a bit of hammer.

The real issue is that there are no built in air chambers in an RVs plumbing. I would suggest, and will likely buy one of these Hammer Arrestor. Simply replace an elbow with a Tee and install the arrestor.

That is a cheap first try. If that does not work a small expansion thank should do the trick.

[Cummins12V98]

ChuckSteed wrote:
If the water pressure is good (you are using a pressure regulator)... not a Camco piece of junk.... then replace the valve

And if you let that foot pedal snap up hard you WILL sooner or later crack the pedal mechanism and be buying a new toilet...

NOT on this model. I have used mine full time since May 2105. I am a release and snap kinda guy!

The down side to the earlier models is the ball can crack and then you are buying a whole new toilet! NOT a replaceable item. Mine did crack but kept it working until last year with various glues until I finally caved in and bought a new unit.

[rhagfo]

ChuckSteed wrote:
If the water pressure is good (you are using a pressure regulator)... not a Camco piece of junk.... then replace the valve

And if you let that foot pedal snap up hard you WILL sooner or later crack the pedal mechanism and be buying a new toilet...

I doubt that replacing the valve will have much effect. I close the valve slowly, but still get a bit of hammer.

The real issue is that there are no built in air chambers in an RVs plumbing. I would suggest, and will likely buy one of these Hammer Arrestor. Simply replace an elbow with a Tee and install the arrestor.

[ChuckSteed]

If the water pressure is good (you are using a pressure regulator)... not a Camco piece of junk.... then replace the valve

And if you let that foot pedal snap up hard you WILL sooner or later crack the pedal mechanism and be buying a new toilet...

[Cummins12V98]

I know they say to push down and pull foot away to let it snap closed. Try quickly lifting the door pedal instead. I have the same toilet and that is what I do in the middle of the night to make less noise and it still functions fine.

[routemaster]

I am bad, it is an Oatey Water Hammer ARRESTER.

[2oldman]

Allworth wrote:
Probably "pressure regulator", but more interesting is which valve closes so fast that it causes water hammer??

From the post title I think it's the toilet.