Taming the Sewer Cow

I intended to write this quick post about how to replace the city water connection on your RV, when ours needing replacing a few months ago. And then this happened…

It all started like this…

A couple days after we got to our favorite Las Vegas RV park—after a long time camping nowhere near pavement—I noticed the small puddle under our RV, near the water heater. I figured it just was the pressure release valve doing its job. That happens.

How to Fix RV City Water Valve

The air conditioner had been on, so I thought it may have been condensation running off the roof, but this was an odd location for that. Learning very early on in our travels to investigate all RV leaks immediately, I decided to investigate further.

Water was not running down the rig like it normally does when the water heater releases pressure. I searched inside near the water heater and found no dampness. I traced all possible routes for water to drip from a leak nearby, and decided to pull out the city water connection…

How to Fix RV City Water Valve

The wood inside the wall was wet! With the connection hanging out of the rig, I reconnected the hose and immediately noticed the check valve leaking. So, I disconnected everything and headed to the nearest RV dealer to replace the city water connection valve.

How to Fix RV City Water Valve

So, about now you’re likely asking what the heck does this have to do with any cows?


Here’s what happened…

The repair was quick and easy, and everything went perfectly. I checked for leaks before securing the connection back in place, and went in to wash my hands. Then I heard it.

Our friends refer to the noise from their water pump as The Sewer Cow. That’s what it sounded like. As soon as we turned on the water, it was like a bloated cow birthing a stillborn calf under our rig. Turn off the water, and would let out a final slow woeful moan.

What is that noise in your RV?

I had just replaced the city water connection with a brand new part. So I knew it couldn’t be that. Right!?

It wasn’t the water pump because no such noise occurred when we turned off the hose and used the freshwater tank. It sounded similar to the way our old water heater used to whine before I replaced that check valve on the old rig. After close inspection I found the source of the noise, and it wasn’t the water heater either.

The new valve I had just replaced was whistling like a pig whenever pressurized. It was even louder outside. I feel sorry for the neighbors we’ve had at the few RV parks we’ve stayed at over the past few months. Yes, we’ve lived with the sewer cow for a few months. We were even growing rather fond of the poor girl at times, but it was time for her to go.

How to Fix RV City Water Valve

How to replace your RV city water inlet flange:

First: Purchase a high quality city water fill valve! I wondered why the one I purchased was $12 when another at the crappy little shop I had to go to was $30.00…

  1. Disconnect your hose and release pressure from your plumbing by opening a faucet. Make sure your water pump is off.
  2. Remove the screws holding the inlet flange in place and gently pull out the connection.
  3. Unscrew the check valve from the plumbing.
  4. Identify the size and type of connection (e.g.; male or female).
  5. Purchase the best RV city water fill inlet with check valve you can find.
  6. Replace the connection. Use Teflon tape on the threads and do not over-tighten or you risk breaking the Flair-it fitting.
  7. Be sure to replace the washer while you are at it. (I learned this the hard way and had to take mine apart the next day!)
  8. Add enough plumber’s putty tape to prevent water from seeping in from the outside.
  9. Connect your hose and inspect for leaks before securing the connection back in place.

How to Fix RV City Water Valve

Did I mention not to buy a cheap connection? Unless of course you want to live with the sewer cow!

No more Sewer Cow with good RV water connection!

B&B makes a good city water fill inlet with brass check valve, at least so far. Good enough that I settled for black, rather than buy another unknown brand. I miss you sewer cow…not.

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