Gonna freeze tonight and for the next couple of nights so I went over to double check my winterizing of the 5th wheel. I was still confused about what I saw from the back of the hot water heater (HWH). My only experience is with our little travel trailer. So I’ll tell you about what we had on the travel trailer versus what we have on the 5th wheel.
On the travel trailer:
[Image from https://rvshare.com/blog/rv-hot-water-heater-troubleshooting-and-parts-2/]The top drawing is what it looked like before I turned any valves. This gave us hot water when we turned on the HWH.
The bottom drawing shows how I turned the valves to bypass the HWH so it didn’t fill up with antifreeze. Later, when we used the travel trailer we flushed fresh water through the system until it was clear of antifreeze. Then I turned the valves back like the above image. More flushing then I installed the HWH plug and refilled prior to turning the HWH on.
It made such good sense.
On the 5th wheel:
I removed a panel under the stove to get to the back of the HWH. Surprise! It doesn’t look the same as the travel trailer’s. There aren’t three valves. There’s one (yellow arrow). Look at this image. When you turn that one valve the cold water diverts upward. What was confusing me because there’s no valve on the HWH line. Isn’t the water now going into the HWH from the top pipe?
Nope. Here’s the story. Coming out of the hot water line of the HWH is a special brass fitting. It is in the black area where the green arrow is pointing. This fitting has a valve and a spring much like in a car engine. It’s called a check valve. This check valve will let hot water out but won’t let anything in. This includes redirected cold water or cold water mixed with antifreeze. This check valve will have an arrow on it to make sure you put it in the correct direction. It should point OUT of the HWH. So what I am seeing in this 5th wheel is it DOES have a bypass. All I have to do is turn one valve to bypass the HWH. Ta-da. That explains that.
Some of you may ask why this is important to me since I use compressed air to clear the lines. Some folks say that water remains in the water pump. Even after blowing the lines out, it is suggested that the owner add antifreeze before the water pump. Lucky owners can get to the water pump easily and an even luckier owner finds a T-fitting has already been added. Take the top off the fitting, add a short length of hose, stick the other inside the jug of antifreeze and turn on the water pump. Slurp, there it goes. And now you have a water pump that won’t freeze and if you put enough in, you will protect any drops in the water lines. I’m suspicious of the cold water line right before the HWH. It slopes down a bit and might have water in it.
As an alternative, if I can find the line that comes directly off the fresh water tank I could install a T-fitting there. Again, it’s all under the floor.
I go water pump hunting. I spent an hour looking everywhere for the 5th wheel water pump. I did a systematic search of the whole RV except what was hidden by the slides in. End to end. Behind every drawer, opened every cabinet and panel. Crawled underneath too. Not much to see under there. It’s an enclosed bottom. There was one small door flap held in place with a zip tie. To whomever cuts something similar… make it nice and big so you can actually see and work in the area. I cut the zip tie and peered in as best as I could. There’s a substantial motor there, and it’s in the right vicinity, but from what I can see there is no water line going in or out. I think it’s the motor that runs one of the slides.
Had Margo call an RV place. They said it could be anywhere. I can tell you exactly where it is not. I’m figuring it’s somewhere in the area between the floor and the bottom protective panel. My last option is to turn on the battery and then the water pump. Pinpoint the sound coming from the pump before it burns up. If under the floor, I was going to cut a three-sided flap below the water pump so I can get to it. However, Margo has forbid me to cut into the underside panel. What the heck. It’s not wooden. It’s like a sort of plastic cardboard. I’d cover the flap with many lengths of Gorilla tape afterwards. I promise.
So we’ll gamble that nothing freezes and if it does we will deal with it after. Personally, I’m a more of a prevent it before it happens type of gal.