Draining fresh water tank

Kbro418

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I am trying to drain my fresh water tank, since the drain valve is not at the bottom of the tank there is a considerable amount of water left in the tank. I have tried to use the levelers to angle the water to the drain but still water is left in the tank. I kept all the spigots open to prevent a suction. Is there another valve that I am unaware of?
 
What model Thor do you have? There is no standardized way Thor has configured their tanks and valves. I find it hard to believe there is no drain in the the bottom of the tank (somewhere).
 
Might want to let people know which coach you have for more specific assistance (2022 Outlaw 38kb).

Most fresh water (FW) tanks will not drain to "dry" status, but that's not required for winterizing. And the little bit left in the bottom should have no effect of a sanitizing and flush procedure.
 
The only issue with some water left in the bottom is it will certainly need to be diluted and rinsed out well plus some disinfectant next season

Luckily mine if on the bottom edge but other units had similar higher drains

My procedure back then was to add a small amount of Bleach or peroxide and flush/rinse next season

Leave the drain valve open
 
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I am trying to drain my fresh water tank, since the drain valve is not at the bottom of the tank there is a considerable amount of water left in the tank. I have tried to use the levelers to angle the water to the drain but still water is left in the tank. I kept all the spigots open to prevent a suction. Is there another valve that I am unaware of?
Use the jacks to tilt the coach; that will leave about a pint on the tank.
They tried that.
 
Turn on your water pump and run the sink faucet until it runs dry, what little is left is not of concern. I doubt very seriously you water pump will laeve 10 gallons of water in the freshwater tank.

For the record my coach a 2019 SOB has NO DRAIN under the freshwater tank. I have fun arguing this fact with others :rofl: I actually have 2 sets of low point drain lines, but for either to drain, I MUST turn on water pump. When I do it not only drains... but drains very fast
 
I have the same problem in our 29m. I found, somewhat by accident, that if I leave the drain open for about a week, it will evaporate out.
 
I’ve never understood the purpose of having BOTH a tank drain and low point drains. I use the low point almost exclusively to drain my fresh tank and my water heater. It’s faster and easier than the alternatives.
 
I’ve never understood the purpose of having BOTH a tank drain and low point drains. I use the low point almost exclusively to drain my fresh tank and my water heater. It’s faster and easier than the alternatives.

I missed who said they had both tank drain & low point drain?

If it was in reference to my post , I should clarify that on my coach; I don't have a freshwater tank drain the way you are alluding too. I do have two sets of drain lines that both happen to be low points under the coach. Each set has tandem red & blue pex line with drain valve. So that is total of 4 pex valves and 4 pex drain lines. I can open all 4 valves and my fresh water will NOT drain. But when I turn on the pump with valves open, it will dump all 70 gallons in less than 5 minutes. Works great and these drains are no where near the freshwater tank. The only way out for water in my tank is through the pump. I guess I could remove the pump and insert my own drain line w/valve before the pump and have both. But to your point, what would be the point :ermm:
 
My coach has 2 cold low point drains, one hot low point drain and a fresh water tank drain. No single drain drains everything. The prior rig a 2015 Challenger also had low point and fresh water tank drains. In that Coach the plumbing for the outdoor kitchen sat lower than the tank drain.
 
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My coach has 2 cold low point drains, one hot low point drain and a fresh water tank drain. No single drain drains everything. The prior rig a 2015 Challenger also had low point and fresh water tank drains. In that Coach the plumbing for the outdoor kitchen sat lower than the tank drain.

Do your "2 cold low point drains & one hot low point drain" drain the tank when opened with water pump off? I mean materially draining the freshwater, not just the residuals left in line beyond the pump, and not necessarily 100% empty.

I can see my Freshwater tank as it is under bed, the way it is plumbed gravity will take it all @100% to the pump which is about 15 feet away in a lower compartment bay (actually my wet service bay). If the pump is on, then all of the water in fresh water tank will come out, when finished the other water already passed the pump in the fresh water supply lines will back drain & flow out one of my 4 low point lines (2 cold/2 hot). Given I drain the Water Heater separately, I am 100% drained after my blowout @ 40 psi.
 
Do your "2 cold low point drains & one hot low point drain" drain the tank when opened with water pump off? I mean materially draining the freshwater, not just the residuals left in line beyond the pump, and not necessarily 100% empty.

I can see my Freshwater tank as it is under bed, the way it is plumbed gravity will take it all @100% to the pump which is about 15 feet away in a lower compartment bay (actually my wet service bay). If the pump is on, then all of the water in fresh water tank will come out, when finished the other water already passed the pump in the fresh water supply lines will back drain & flow out one of my 4 low point lines (2 cold/2 hot). Given I drain the Water Heater separately, I am 100% drained after my blowout @ 40 psi.

I haven’t tried them without opening the tank drain. I’ll give it a try when I drain my rig prior to it going in for the final warranty punch list.
 
I have 4 low point drains and a large tank drain at the bottom of the side wall

All 5 must be opened to properly drain the system

Don't forget to open every faucet and the single handles must be centered when opened so both hot and cold sides drain

And don't forget the main filter and also ice maker tubing

Washing machine must be ran and antifreeze used for safety
 
I have 4 low point drains and a large tank drain at the bottom of the side wall

All 5 must be opened to properly drain the system

Don't forget to open every faucet and the single handles must be centered when opened so both hot and cold sides drain

And don't forget the main filter and also ice maker tubing

Washing machine must be ran and antifreeze used for safety

Where is your line that feed the water pump, and when your pump has pumped all the water that it can physically pump from your tank; how much water do you think is still left in tank? OP is saying he has 10 gallons left :confused:
 
I missed who said they had both tank drain & low point drain?



If it was in reference to my post , I should clarify that on my coach; I don't have a freshwater tank drain the way you are alluding too. I do have two sets of drain lines that both happen to be low points under the coach. Each set has tandem red & blue pex line with drain valve. So that is total of 4 pex valves and 4 pex drain lines. I can open all 4 valves and my fresh water will NOT drain. But when I turn on the pump with valves open, it will dump all 70 gallons in less than 5 minutes. Works great and these drains are no where near the freshwater tank. The only way out for water in my tank is through the pump. I guess I could remove the pump and insert my own drain line w/valve before the pump and have both. But to your point, what would be the point :ermm:



I wasn’t really responding to your situation in particular. Just making conversation. Though my basic point, as you note, is that “you” shouldn’t miss a tank drain. The low point drains and pump works as well or better anyway.
 
I wasn’t really responding to your situation in particular. Just making conversation. Though my basic point, as you note, is that “you” shouldn’t miss a tank drain. The low point drains and pump works as well or better anyway.

:thumb: Yes sir :coolsmiley:

I will never forget getting really frustrated with the Service Tech who grew impatient with me because I didn't see nor could I find the tank drain that they insisted was there. It was NOT!!! :nonono: Winnebago had come to the conclusion you made that the tank drain was NOT necessary and removed it from my version of the model. Only 3 Blue pex lines connected to my freshwater tank. Incoming, outgoing, and overflow. The outgoing is on one bottom side corner that goes straight to water pump. I use to think that if my pump were to go out; then I could not drain my tank :facepalm:, then one night with a few beers, the lights came on:angel: if I had that situation, I could just disconnect the line feeding the water pump and the water tank could drain 100% by gravity!!!! :coolsmiley:
 
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dk - edumacate me... :coolsmiley: when you do your "40psi blowout" do you have the pump ON - even briefly? Would that be necessary, or would it depend on how the plumbing is routed? I'm thinking about adding this to my winterize routine.
 

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