Draining fresh water tank

[RJ Schubert]

Hi all. I have a 2018Quantum RQ29. I want to drain the fresh water tank. I've searched this forum, and depending on the model, there should be a valve to open the drain. I've checked the manual also and it mentions opening a valve. I have an outside spigot, and there is a clear tube running from the outside spigot to the bottom of the fresh water tank. My tank is under the bed. I've looked a few times and don't see any valve inside near the fresh water tank and pump.

I've attached pictures showing what I have. Any help with how to drain the fresh water tank (I know I could just open all of the faucets) would be greatly appreciated.

R.J.

[16ACE27]

From your pictures there's no valve at the tank connection so the key must be that spigot. I'm not familiar with it but could it be something like this with a broken handle?

[DavidEM]

Working backwards starting with pic 4:

4. This looks like the drain connection to your tank.

3. This is the antifreeze flush valve. You connect a hose to the verticle tube after removing the hex plug. Then drop the hose into a jug of antifreeze, turn the chrome plated valve a quarter turn and turn on the water pump. It will then suck antifreeze from the jug.

2. This is the drain valve spigot that is connected to the bottom of the tank as in #4.

1. Is this the same tube shown in #4?

This is not how Thor plumbed the drain on my 2021 Axis and yours is likely to freeze up the outside spigot in sub freezing temps. You can replumb it to avoid this if it important, but it may be tough to find a place to reroute the hose to an inside valve.

David

[Lt Keefer]

The outside spigot is a valve. Turn the top 90 degrees and water should flow out. If it doesn't, remove the screws and pull it out from the wall. It can then be replaced with one from Amazon.

[RJ Schubert]

Hi Ace. The handle turns and I didn’t see any obstructions in it. What’s curious though is that I don’t see any water in the clear line from the tank to that spigot.

[RJ Schubert]

Thanks David. I’ll wrap som insulation around it. But I do plan to winterize the RV so I think that I will be ok.

[16ACE27]

Originally Posted by RJ Schubert

Hi Ace. The handle turns and I didn’t see any obstructions in it. What’s curious though is that I don’t see any water in the clear line from the tank to that spigot.

Not to be a smarta__, but how do you expect to see clear water n a clear tube?

You may see bubbles in a turbulent flow, but at the bottom of the tank that won't happen until it is almost empty.

[RJ Schubert]

Thanks Lt. I think Ace suggested the same thing. I’ll order a new valve and see if there is a vacuum preventing the water from flowing from the tank to the valve.

I did download the water schematic from Thor and it shows two low point drains. I haven’t located those yet either.

[RJ Schubert]

Fair point Ace but I did squeeze the tube and I didn’t feel resistance. I’ll order the new valve and update the forum.

Thanks again

[RJ Schubert]

Correct on all points

[RJ Schubert]

Hi Ted and all. I changed out the spigot and no difference. There is not water coming out of the hose. To me that means that the water is turned off above that point.

I’ll check under the bed again and see if I missed a valve somewhere.

Also I can’t locate the two low point valves. The schematic from Thor shows one low point near the outside refrigerator and the other up passed the batteries. Any help with locating the low points would be appreciated.

[ghnl]

If you can safely get under the RV (and out again...), look for short hoses hanging down. Those are probably the low point drains. Next you have to figure out where the valves are inside the rig. But knowing approximately where to search might help.

[RJ Schubert]

Thanks ghnl. I have looked underneath for the two low point drains (the red and blue water lines). They aren’t where thor says that the should be in the schematic. I will keep looking for them and update the forum

[16ACE27]

Originally Posted by RJ Schubert

Thanks ghnl. I have looked underneath for the two low point drains (the red and blue water lines). They aren’t where thor says that the should be in the schematic. I will keep looking for them and update the forum

All my drains have white tail pieces.

[ghnl]

Another thought (they occur randomly...). That quarter turn black valve could be clogged. Mud wasps build nests in the most inconvenient places.

[16ACE27]

Originally Posted by ghnl

Another thought (they occur randomly...). That quarter turn black valve could be clogged. Mud wasps build nests in the most inconvenient places.

See post #11 - he replaced that valve.

[RJ Schubert]

Hi. I just replaced that today. The water lin going to does not have water in it. Check out the pictures that I uploaded.

Thanks.

[willis]

our quantum ws31 has the two low point drains under the drawer beneath the refridge. they are routered out of the floor material and not easy to get to. the drain for our tank which is under the bed is the spigot outside you showed, i would blow low pressure air into it from the outside to see if its obstructed going to the tank, it may be they didn't get a clear opening when installing the fitting on the tank.

[RJ Schubert]

Thanks very much. I’ll give the air a shot. I was thinking of that also. I’ll check under the fridge

[willis]

ours is a 2018 also so should be the same but have found out that thor is consistent in building them. good luck drawer is not easy to get out if you have large hands as i do but then you get to clean out all the stuff back behind it.