Dishwasher water pressure issue

[rvluckyorwhat]

Ever since we bought our RV (new), we have noticed that the Fisher-Paykel dishwasher often is unable to complete a wash cycle. When it stops, it spits up a "U6" error code which indicates insufficient water pressure. I find that whenever we use our water pressure regulator outside (which is supposed to keep the pressure between 40-50 psi, the dishwasher usually stops. Without the regulator, it's hit or miss and depends on the RV park (and presumably, the pressure at the spigot).

I have been thinking about:
- buying a regulator that is set to 50-55 psi ($15)
- buying an adjustable regulator ($40, which would be worth it, but I've yet to find one with good customer reviews)

In the meantime, I called the manufacturer of our RV (it's a 2014 Thor Tuscany) and asked what the max water pressure is that they recommend. The customer service contact said don't exceed 50 psi. So maybe a more powerful or adjustable regulator isn't such a good idea after all. Next I called Fisher-Paykel and asked what pressure they require. I got a very indirect answer. They would not give me a pressure requirement (even though the error code says insufficient pressure). Instead they told me that the error I'm seeing will occur when the dishwasher can't pull 0.65 gal/min. Which sounded really low, but as an experiment, I measured flow through my kitchen sink and shower head just now with my regulator installed and they were only around 0.75 gal/min. The dishwasher has failed 5 out of 6 times that I've tried to run it at this location, meaning it ran to completion once. The other times, it would sometimes run for 10-20 minutes before failing, and sometimes would stop after 2-3 minutes. So I suppose I am at the cusp of what the dishwasher will tolerate.

I have also learned through measurement that my flow rate at my faucets doesn't seem to change regardless of whether I put the regulator at the spigot end or at the RV end of my 30 foot long hose, which kind of surprised me.

After all this, I decided to purchase a water pressure gauge so I can see what my regulator is providing, and also so that I can see what pressures seem to work and not work at various parks as we travel.

My questions are:
- Do others with Fisher Paykel washer drawers observe this problem?
- Have you found a solution?
- Do others have any other suggestions about what I might try? (besides the obvious --- "wash your dishes by hand")

Thanks!

[rkentzel]

The above is correct check the water line for kinks and check the connection to the diswaher

[dougrainer]

Your problem is probably simple. One of the water lines going to the Dishwasher is either partially clogged or kinked somewhere. The Dishwashers will work on either water pump or City water. ALL the Dishwasher is telling you is---I don't have the water to do the job. It does NOT measure pressure. Doug

[Roadpilot]

We have a Fisher Paykel drawer and have never had this problem. But I only use the external water hookup to fill the tank. Normal operation is to run off the tank with the pump that's in the motorhome and it's capable of moving a lot of volume. We could have the DW and clothes washer running while someone is using the shower.

External connections are hit or miss in terms of pressure and/or flow rates.

[quasi]

RVLucky ~ Your problem isn't pressure, it's flow rate. With the external screw on regulator your volume is seriously reduced. Think of it like a nozzle. You can have all the pressure in the world but the nozzle restricts how much water (in volume) you get through the line. The best solution (IMHO) is a whole house regulator from the Borg and install it inside your unit where the city water line comes in. They're adjustable and have plenty of volume. Plus, you won't leave it screwed to the spigot when you drive off . . .

Just my $.02, YMMV

Jim

[rvluckyorwhat]

The high volume regulators are rated at over 50 psi, which was the limit that the Thor customer service personnel recommended.

[ScottG]

Get a "high flow" or high "volume" regulator like are available from Camco. They pass a lot more water through.
Or you can get a Watts whole house regulator but the $12 versions I suggested above will work great.