Water Drain Valves

[Metoo]

I have a 38FQ that is in storage so I don't have access to just run over and check this out. What I want to do is put a 1/4 turn valve on the fresh water drain but I want to be able to connect a garden hose up to it to direct where I want it to drain. What is the size of the thread on the end of the hose that has that cap on it?

[NH_Bulldog]

Any fresh water tank drain I have ever seen already has a valve installed. There are many styles and types, but I can’t say that I have ever seen a fresh tank drain that was capped.

That being said, there is no “standard” (even among the same floorplans, they use what is there on any given day, which can often vary even on the same day) so you will really need to get your eyes on it in order for anyone to give you accurate guidance.

[Don77]

On my last trailer I did just that, I installed 1/2 FMPT Ball valves on the low point drains, and a hose bib on the fresh water drain, worked great.
My 2018 Springdale low point drains are just capped, I did put a hose bib on my freash water tank drain,will be doing the same on the other low point drains.

Don

[Metoo]

Thanks Don that is what I will look into.

[GlasNav]

A friend of mine is the second owner of a Rockwood, and the drain valve on their fresh water tank is a 1 1/2" cable actuated dump valve. I don't know if that was original equipment or if the first owner refitted, but that is sure nice to be able to rinse and dump the potable tank.
Why my jealousy, our 25RDS has a 3/8" quarter turn barbed valve on the bottom of a 60 gallon tank, you do the math, it takes forever to drain the tank. I don't know if this is the norm, or it was simply what was laying around during covid?

[NH_Bulldog]

Originally Posted by GlasNav

A friend of mine is the second owner of a Rockwood, and the drain valve on their fresh water tank is a 1 1/2" cable actuated dump valve. I don't know if that was original equipment or if the first owner refitted, but that is sure nice to be able to rinse and dump the potable tank.
Why my jealousy, our 25RDS has a 3/8" quarter turn barbed valve on the bottom of a 60 gallon tank, you do the math, it takes forever to drain the tank. I don't know if this is the norm, or it was simply what was laying around during covid?

Mine has the same micro-valve (pre-covid). When we picked up the trailer when we bought it 750 miles from home it was filled with water from our walkthrough and it took until we were about halfway home before it all drained out. Not sure what our new one will look like but I am hoping it will be the large diameter gate valve dump, but not getting my hopes up.

[cougar23]

Our 2023 Cougar 23MLE has the small fresh water drain with a valve. Draining the tank has not been a problem since I never fill the tank full and when parked at home it's on a gravel pad.

[GlasNav]

Originally Posted by cougar23

Our 2023 Cougar 23MLE has the small fresh water drain with a valve. Draining the tank has not been a problem since I never fill the tank full and when parked at home it's on a gravel pad.

My issue is that it takes forever to drain the tank, and without any flow volume while draining, if there is sediment etc, it will remain in the tank...

[JRTJH]

Careful what you wish for with a 1.25" fresh water tank drain.....

If you are draining on concrete, all you have to worry about is maybe wet shoes/knees... Do that same thing on dirt and you'll need a shower every time you empty the FWT. Then there's the "rush of water" and what it can do to a gravel/limestone parking pad.....

So, as with most things related to RVing, there's good and there's bad about a 1.25" high flow drain just as there's good and bad about that "spindly little dripper" drain...

[Metoo]

That is why I want to be able to attach a garden hose to direct the out flow

[flybouy]

I don't see a huge advantage of stepping down a 1 1/4" drain line to a 1/2" or 3/4" hose bib over a 1/2" unrestricted drain. What am I missing?

[Metoo]

No I don't have an 1 1/2 drain the low point is going to be some where around 1/2 or 3/4. Not sure right now of that size.

[JRTJH]

Originally Posted by Metoo

No I don't have an 1 1/2 drain the low point is going to be some where around 1/2 or 3/4. Not sure right now of that size.

Your drain, if it's not a 1.25" drain, is going to be 1/2" PEX. I'd guess you have the "rubber gasket type" screw caps on the low point drains and the FWT drain.

You can easily cut the PEX above the existing terminal cap fitting and use either a sharkbite valve and a sharkbite 3/4" garden hose fitting, or better yet, if you have a PEX crimper, just buy a PEX 1/4 turn valve and a female garden hose fitting, crimp them on the existing PEX and you're done.

If I were you, I'd also buy an "end cap" to screw into the female garden hose fitting, to keep bugs and stuff out of your FWT drain line.

[Metoo]

OK that looks like something I'll look into thanks

[Don77]

Originally Posted by JRTJH

Your drain, if it's not a 1.25" drain, is going to be 1/2" PEX. I'd guess you have the "rubber gasket type" screw caps on the low point drains and the FWT drain.

You can easily cut the PEX above the existing terminal cap fitting and use either a sharkbite valve and a sharkbite 3/4" garden hose fitting, or better yet, if you have a PEX crimper, just buy a PEX 1/4 turn valve and a female garden hose fitting, crimp them on the existing PEX and you're done.

If I were you, I'd also buy an "end cap" to screw into the female garden hose fitting, to keep bugs and stuff out of your FWT drain line.

I used 1/2 inch pipe thread fittings on my previous trailer and plan on using them on this one.
Easy to do as the PEX fittings are 1/2 inch MPT.

Don

[Phil Saran]

On my present Keystone and also my previous one the fresh water drain was
a 1/2" PVC pipe.