Draining Holding Tank

[Lbatt]

I just purchased a used Thor Ace 27.2 and there are two holding tanks in the bay behind the rear tires. One has a black handle, the other a grey handle. From the directions in the exceptionally poorly written manual, that you hook up the hose, pull the black handle first, then the grey. That makes sense.

The Features list of this RV does state it has TWO grey water tanks.

What DOESN'T make sense is in the bay in front of the rear wheels is another tank with a black handle, and because the rear tires separate the two bays, there is no way the one drain (either one) can drain all three tanks.

This bay also has the outside shower and the "sanitize flush" hookup for an outide hose.

There's no mention of having to remove and move the drain hose.

Any ideas on how to proceed?

Thank you.

[blw2]

I have no idea about the color coding
but generally the idea is to dump blackwater first, then chase with grey water to rinse the hose
blackwater tank would likely have a larger pipe coming to the drain.
and the blackwater tank would be under the toilet.

make sure the black tank is fairly full before draining
then connect the drain hose to the dump
then open the blackwater
then when that's done close it and open the grey water

The rinse would be a nozzle inside the tank for rinsing it out after. No need really in doing that every time (or at all really). Plenty of us have RV'd for years without one even installed.
I suppose it could also be a way to fill the black tank that's not very full before dumping it if you have to

[mash557]

My Challenger has two black tanks and two grey tanks. Each black/grey set of tanks has its own outlet and hose must be moved or get two hoses with a wye which is what I have. If you don't have a grey mid tank, then I would dump that one first, then move to the rear set and use that rear grey tank to flush your hose out. The Saniflush also does a good job of cleaning the tank and hose.

[fhenn]

Go into Motor home tech and down load ed's manual there is a sticky there

[Bob Denman]

http://www.thorforums.com/forums/att...1&d=1531956752

[Beau388]

You have a gray water tank for the kitchen sink and another one for the bathroom. Your dealer during the PDI should have explained this in detail. The black water drain pipe is a 3" pipe. It may or may not have a black handle on the knife valve depending on the installer. ALL gray water drains have a 1.5" pipe coming into the knife valve. The color of the handle should be gray or black; hopefully, a different color from the other, but never say never. Some coach designs have an intermediate knife valve located near the outlet for the rear gray water tank in the rear to prevent water remaining in the line after draining (you don't want the drain pipes to have water in them in freezing weather. Hopefully some one who had a thorough PDI with an ACE 27.2 can explain it all to you. By the way most wye valves swivel up and down. The outlet is stiff but can be aligned with the hole in the bottom of water bay.

[16ACE27]

Originally Posted by fhenn

Go into Motor home tech and down load ed's manual there is a sticky there

The OP does not have an Axis/Vegas.

[JamieGeek]

Originally Posted by Tfryman

The OP does not have an Axis/Vegas.

Many of the topics in the manual are general enough for all Thor motorcoaches.

[16ACE27]

Originally Posted by JamieGeek

Many of the topics in the manual are general enough for all Thor motorcoaches.

While that may be true there is nothing in Ed's manual that would answer the OP's question regarding draining the second gray tank.

[JamieGeek]

Originally Posted by Tfryman

While that may be true there is nothing in Ed's manual that would answer the OP's question regarding draining the second gray tank.

True.