Thetford toilet wont stop filling when other faucets or washer is running.

We have a 2104 Landmark Key Largo. While connected to city water, if any faucets or the washer are being used while flushing the toilet, the bowl will not quit filling after a flush. Replaced with new stool and have same issue.

Water pressure shows 50 PSI with the good adjustable pressure regulator. Issue is not present when using holding tank and pump. I believe the volume/pressure is more consistent when water pump and holding tank are in play, because the water has already passed through filter and softener when filling the tank and therefore less volume/pressure variation..

1) Have water softener and two canister filer system installed (1 sediment filter and 1 carbon filter).
2) Have replaced the stool with new toilet Thetford, same results.
3) Thetford states that there is a low pressure rating and will cause the issue.
4) Turn off the water at the pedestal and back on it stops filling.
5) Issue is not present when using holding tank and pump.

My question is, if I would install an Actuator Tank, would that help to compensate for the loss of volume/pressure when on city water and resolve the problem?
 

mlpeloquin

Well-known member
I would look at the diameter of the hose and the through put of the filters. When demand is high and the line is restricted, the pressure drops. It maybe on the output of the filters unless you have a problem with the water softener. Try removing the filters one at a time and see if the problem goes away. Just remove the filter cartridge not the entire assembly. You may have to put a larger capacity filter to handle the through put.
 
I would look at the diameter of the hose and the through put of the filters. When demand is high and the line is restricted, the pressure drops. It maybe on the output of the filters unless you have a problem with the water softener. Try removing the filters one at a time and see if the problem goes away. Just remove the filter cartridge not the entire assembly. You may have to put a larger capacity filter to handle the through put.


Thank you. I did use 3/4" PVC pipe when installing the filters for that reason. Also, I am using 5/8" water hoses all the way from faucet pedestal to the filter input. I will also touch base with RV Water Systems and see if they have a recommendation, it is their filter system.

I appreciate your thoughts
 

danemayer

Well-known member
Sounds like the water flow is being reduced somewhere.

When using the shower, how does the water flow compare between pump/tank and campground water? If it's better on the pump/tank operation, you have a restriction somewhere. Could be the filters - I stopped using the 1 micron filters for that reason. I've also seen people have restrictions inside the pressure regulator - even the good adjustable type. Bypass each device to see if the water flow improves.
 
Sounds like the water flow is being reduced somewhere.

When using the shower, how does the water flow compare between pump/tank and campground water? If it's better on the pump/tank operation, you have a restriction somewhere. Could be the filters - I stopped using the 1 micron filters for that reason. I've also seen people have restrictions inside the pressure regulator - even the good adjustable type. Bypass each device to see if the water flow improves.

Thank you Dan. I agree that I believe it is in the filters. Whenever I change them, it seams to be better for a bit. I will follow your advise and try eliminating the two items you have mentioned. Do you think the actuator tank may help?
 

MTPockets

Well-known member
An accumulator tank is a great investment if you use the on board pump often. Your pump won’t come on except when pressure drops. That accumulator tank will keep pressure more consistent.
 

danemayer

Well-known member
Thank you Dan. I agree that I believe it is in the filters. Whenever I change them, it seams to be better for a bit. I will follow your advise and try eliminating the two items you have mentioned. Do you think the actuator tank may help?
It's possible it might. Assuming you have good pressure to fill the accumulator tank, the tank might provide improved flow. If you're only trying to improve the toilet operation, a relatively small accumulator might be helpful. Can't say for sure.

But, I'm a fan of finding and fixing the root problem, if possible, rather than adding a workaround.

I used to use a dual filter system to trap sediment and filter out micro-organisms and bad stuff. But the 1 micron reduced water flow after a short while. So I started just using the 10 micron sediment filter. Then after the canister started leaking, I switched to Walmart filters. No more problems.
 
It's possible it might. Assuming you have good pressure to fill the accumulator tank, the tank might provide improved flow. If you're only trying to improve the toilet operation, a relatively small accumulator might be helpful. Can't say for sure.

But, I'm a fan of finding and fixing the root problem, if possible, rather than adding a workaround.

I used to use a dual filter system to trap sediment and filter out micro-organisms and bad stuff. But the 1 micron reduced water flow after a short while. So I started just using the 10 micron sediment filter. Then after the canister started leaking, I switched to Walmart filters. No more problems.

Agreed, I want to figure it out and will try your suggestions. We do a lot of Boondocking so thought the Accumulator Tank is something I have wanted to reduce noise at night from the flushing. If this serves a dual purpose, maybe DW will give me the OK :).

Thanks to all for your help and recommendations.
 

uncledon

Her chauffeur
Agreed, I want to figure it out and will try your suggestions. We do a lot of Boondocking so thought the Accumulator Tank is something I have wanted to reduce noise at night from the flushing. If this serves a dual purpose, maybe DW will give me the OK :).

Thanks to all for your help and recommendations.

I just installed an accumulator on my rig and had one on an earlier rig. I have never seen or heard of them installed in the city water circuit though. They are usually installed immediately after the 12 volt water pump. I'm not saying that you couldn't, but I'm not sure if it would work correctly since you will find vastly varying water pressures across your travels and the accumulators require a set air pressure over the bladder that correlates to system pressure.

I found this PDF file from Shurflo that may help answer some of your questions:

http://www.depcopump.com/datasheets/shurflo/182-200 Installation manual.pdf
 
Update.............. Thank you to everyone who commented.

I have installed the accumulator tank and the results are in. I can now run the kitchen faucet while the washer is filling and still flush the toilet. My water softener and both filters are still in the line. While I was at it, I implemented the suggestions of others as i did the work.

1) Installed 2 Gallon accumulator tank with a "T" off of a current cold water line.
2) Added a shut off to the accumulator tank after the "T" to isolate if needed.
3) Installed a "T" at the bottom of the accumulator connection with a line through the compartment wall and plugged it for draining and winterizing.
4) Installed a shut off valve above the floor behind the stool for future issues.
5) Used Sharkbite fittings for the PEX pipe, more expensive but awesome products.

Prior to this not only was there an issue with the stool filling the bowl after flushing, it really never had enough volume to do a great job of flushing out the bowl. Stool is as good or better than new. I would recommend this fix if anyone has had the same issue.
 
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