After reading a lot of posts, I'm still not sure which topic describes me... Here's my situation-I have a Gillig chassis, with HWH levelers. The control panel has 4 joysticks to raise and lower the jacks, and 2 switches to turn on/off and "bleed". After driving the RV, I put down the jacks, then "bleed" system.. Am I deflating the air bags? Now, my problem is, the "bleeding" process isn't working anymore. I don't hear the air being released. However, by the next time I start the RV, I noticed that my air pressure is "0".(on dash gauge) So, have I addressed a lot of topics here or what?? Anybody have any answers, or am I talking off the wall??

I suggest: "Am I deflating the air bags?"
Yes.
"I noticed that my air pressure is "0"(on dash gauge)".
While you are parked, the air tanks/bags are "leaking" air so it is empty -0 pressure- at startup many hours later. The gauge is reading pressure in the tanks, of course; not the actual bag pressure. It would also be empty if you parked overnight without bleeding the tanks or putting the jacks down.
n.b. I partially bleed the bags first and then lower the jacks. This allows leveling without extending the jacks as far.

So Gunner, you said that you partially bleed the bags first.. Well, mine won't "bleed" by using the switch. Is it ok to just let it "leak" out slowly? The last thing I want is to damage the air bags.

I also have an HWH leveler system but it is different model --- hopefully the basics are the same. I also stuggled with a sequence that worked which I will share. When stopping for the night: 1. Depress the air brake button. 2. Turn off the main engine. 3. Turn the ignition key back to the "on" position (don't restart). 4. Turn on the leveler. 5. Bleed or kneel the coach to suit. Mine always starts in the front. 6. Then level the unit

If I don't follow this sequence exactly, the leveler will not work.

Hope this helps!

"Is it ok to just let it "leak" out slowly? The last thing I want is to damage the air bags."
Yes. It is going to "leak out slowly" anyway (from what you've described about zero pressure later). The jacks may be put down anytime before, after, or during the air discharge. Remember that when the engine is running air is being sent to the tanks, offsetting the "bleeding"; that's why Frank kills the engine and then turns the ignition back on to energize the levelers.
IMHO: The bags will only be hurt by retracting the jacks suddenly with no air in the tanks/bags, which suddenly drops the coach onto the deflated bags. ALWAYS run the engine and get the air up to normal before retracting the jacks. In my case, the extended jack feet are clear of the ground anytime the air is at normal pressure.
More: When I stay at a level location for extended periods (more than 2 weeks) I put blocks up close to the (retracted) jack feet while the tanks/bags are full then kill the engine and forget it. It settles overnight onto the jacks (still retracted) and the coach is supported ON THE JACKS although they are not extended and there is no hydraulic prssure on them. They are then, in effect, perfect chassis support points with no binding on empty bags or suspension items.

thank you Frank and Gunner.. Frank, that's the same steps I take.. But, it will not bleed.. I'm beginning to think that something is wrong with the switch.. And, since my coach is stationary for a period of time, I also put something under the jacks, so that it will be level at all times.