Community Forums

MDougherty · 03-12-2017, 01:11 PM

Hello, I have searched the Thor Industries Owner's Forum for the past six months of threads and couldn't find any discussions about this particular problem.

We usually use RV park water, so we don't use the pump except while driving from one location to another. Yesterday we decided to use the water in the storage tank so that we could replace it with fresh. During this process, I noticed that the pump is always running.

The pump seems to run at a different speed when all faucets are closed and there is no demand. When a toilet is flushed or a faucet is opened, the pump kicks into "high gear" and then returns to "low speed" when the draw stops.

Is this "normal" or is there something wrong with my water system? I would think that the pump, or some part of the control system, would monitor line pressure and shut the pump off when there is no demand. Is that a bad assumption?

Does the pump have an integral pressure controller that could have gone bad?

Is there another separate pressure module that might need replacement?

During my tank draw down yesterday I noticed that there was a large wet spot below the coach near the water service cabinet, but it was not possible to see where the water was actually coming from.

I am wondering if there might be a small leak somewhere that keeps the pump running continuously (to maintain pressure). I have not observed any wet spots in the basement.

Does anyone out there have any experience with this particular issue?

I look forward to your advice!

tcopeland · 03-12-2017, 01:41 PM

Sound as if you have water passing somewhere.

kjburns · 03-13-2017, 11:32 PM

Make sure the valve in the wet bay is set to the right position.

Old-Biscuit · 03-13-2017, 11:39 PM

Large wet spot
Pump runs continuously

LEAK

Need to FIND/Isolate/FIX ASAP

soonerdave · 03-14-2017, 04:35 AM

Check to see if your tank level is going down, if not your pump is bad and bypassing internally, it can't build pressure and the pressure switch won't turn it off.

powerboatr · 03-20-2017, 08:29 PM

Quote:

Originally Posted by tcopeland

Sound as if you have water passing somewhere.

yep something is open or leaking.
check water heater by pass valve for fully closed
checks low point drain valves for security.

mine will loose prime every now and then and run for an extended period.

bam565 · 03-20-2017, 08:45 PM

Agree with KjBurns. Make sure your water selector valve is in the "normal" and not the "Fill" position. My pump will run continuously if I forget to get the selector back to the normal position after a tank fill. In order for the pump to run continuously, there would have to be a serious leak. More like a blown fitting somewhere.

MDougherty · 03-21-2017, 09:38 PM

The pump sounds very different when water is actually being delivered (somewhere in the coach, at a faucet or washing machine) and when it just seems to be dead heading.

I have been unable to detect any leakage so far. The water I reported earlier might have just been runoff from the a/c system.

I have the water valves in the correct position (source valve = internal tank; normal/tank fill valve is set to normal) when this malfunction occurs. I am almost certain that an incorrect valve position is not the problem.

There is no leakage in the Aqua Hot cabinet.

The system low point drain valves are both closed and not leaking.

Somebody said that there is a pressure switch in the system ... is it an integral part of the pump, or is it a separate component? Perhaps it needs to be replaced.

Or, maybe, as someone else suggested, the pump might lose its prime and therefore cannot satisfy the pressure switch, so it runs forever.

Maybe the water pump is defective and simply needs to be replaced.

It would be helpful to see a piping and control diagram, to see how the water system actually works, and where the various components are physically located. Do any of you guys have such documentation for a Thor water system?

I look forward to being able to leave the water pump switched "ON" while we are driving down the highway. As it is now, it keeps chugging away continuously down below. I am worried that it is eventually going to burn out and leave us without any water service while in transit.

soonerdave · 03-22-2017, 04:37 AM

Mac, if you call Thor they will send you all of the diagrams for your coach by email as a PDF. You can get wiring, plumbing, pretty much everything. Many owners, including myself have asked and gotten the diagrams the next day. And yes the pressure switch is a part of your pump.

MDougherty · 04-12-2017, 10:37 AM

Hello, thank you all for the advice. As it finally turned out, a detectable leak finally developed in the area of the water pump, so we only used it when absolutely necessary, as we drove home from our trip to Florida. The motorhome has now been returned to the dealer for final repairs under warranty. They will find the leak and solve the problem. By the way, when I reported this to Thor customer service they sent me a new pump right away (it was waiting for me when we got home from our trip). The new pump has been given to the dealer in case they need to replace the pump to solve the problem.

2016 Thor Tuscany 45AT
Mike & Terry FMCA F457981