Using the drain in the water bay marked fresh water, I can only get 2/3 of the water out. 1/2 stays in the tank. How are you all dumping all of it?

Our rig has a 1/2 ball valve in the fresh water drain which drains the tank completely and prety fast.

I'm not sure what year Tiffin went to the larger valve, but if yours is the smaller style, it may hap to tip the rig using the jacks towards the side of the coach where the drain is.

I see that my post erroneously states 1/2 of fresh water left in tank. Should have been 1/3. My jacks are automatic & self leveling. Can't tilt them or the coach. Other suggestions?

I 've been told that if you open the gray tank about 1/2 way thru the black dump, the flow will increase greatly and draw the black out better. TMH @ Red Bay offers this advise. It seems to work.

quote:

Originally posted by Magoo:
My jacks are automatic & self leveling. Can't tilt them or the coach. Other suggestions?

What brand of jacks do you have? I thought I recalled that you had an Allegro Bus and assumed you had the HWH jacks. Although the HWH jacks are automatic self leveling (as mine are also) they can be operated manually as well.

Your model may be different, but on the current units, by simply turning the unit on and pressing the appropriate up/down arrow on the side or end of the rig you wish to raise you tilt the rig. You don't want to activate the self leveling feature, which in my case is done by hitting the HYD button twice.

Magoo,

FWIW, the OEM LED Tank Level Monitor Panel is notoriously inaccurate. For plain, fresh water you’d think it should be more accurate than the black and gray water holding tanks, but there’s other things to consider. These “things’ include the locations of the level sensors in the tank as well as the slope of the motorhome.

The fresh water tank on my Bus is approx. 7-1/4” high on the street-side. (It’s slightly taller on the curb-side but let’s not complicate matters.) My OEM level sensors (SS screws) are installed at 1-1/8”, 1-3/8”, 3” and 6” from the bottom. The screw at 1-1/8” is the “ground" screw. Ignoring the fact that the tank averages taller than 7-1/4”, when the water hits the sensor sensor (screw), the approx. water volume is 20% of the tank’s capacity. At the third sensor the water volume is 41% and when the fourth sensor is touched by the water, the water volume is at 83% of the tank’s capacity.

What does all this gibberish mean? Only that the OEM Tank Level Monitor Panel cannot be used for accurate calculation of the tank’s contents. If I want the tank to be full, I have to fill it until the water runs out the tank overflow in front of the curb-side rear wheels, not just watch the Monitor Panel. If I want the tank to be empty, I open the drain valve and make sure the tank drain is at the low point.

Ah ha! Low Point! My fresh water tank has the piping connection made at the lowest point possible, at the rear of the tank, on the street-side. So, if I want to drain the tank I simply adjust the slope/pitch of the motorhome so that the curb-side and the front are slightly higher than the opposite sides. Remember, I said my piping connection was made at the, “lowest point possible”. This tank connection still is about 1/8” off the bottom of the tank, but tipping the motorhome helps to minimize the water that can’t drain out.

Another interesting point is that my motorhome’s self-leveling, automatic jacks need some fine-tuning at each stop. After bumping and banging away on the road all day, I wouldn’t expect them to be 100% accurate. I have the HWH system and the system should be recalibrated periodically. In any event, the jack system gets the motorhome close to level, but I always put a level on the frame of the bathroom door and touch up the adjustments manually. (I use the bathroom door because that’s the most obvious thing that swings when things aren’t quite so level.)

So, what’s the point of all this? First, I’d check and see if you can tip your motorhome using your jacks in the manual mode. I’d guess you actually may be low on the curb-side and maybe the rear, too. If that’s the case, you’ll never get all the water to drain because the tank outlet is lower than the drain valve.

Second, don’t rely on the Tank Monitor Panel to tell you how much fresh water is remaining in the tank. You may be able to see the fresh water tank and be able to see the level of fresh water in the tank. (Get down on your knees with a flashlight.) The tank is made of translucent plastic and should sit under the black and gray tanks. If your Monitor Panel shows it as 1/3 full but the water level is less than the second sensor from the bottom, you have a Monitor Panel problem. If the water level is at or above the sensor, you have a leveling problem.

Hope this helps . . and good luck.

Chuck

There is gravity drain valve for the fresh water tank which is located between the black and grey dump vales in the pan of the sewer compartment on my coach. You could also use the fresh water low point drain valve along with the water pump to "pump out" the fresh water tank. That valve, along with the hot water one, is located behind the water filter canister in the rear left-hand back corner of the sewer compartment.