I did a search, but could not find a thread to answer my question. I thought I had seen this topic on here before, but here we go...
Does anyone else have problems maintaining air pressure in their tanks (both of mine) over night? Seems that I lose all air pressure just overnight. And now it seems that my front tank is slow to get up to pressure once the motor is started. I wonder if I am heading for a problem?
Bruce

I also loose pressure, sometimes in a short period of time [like overnight] and sometimes it seems to hold for several days. Seems to be dependant on the fluctuations in temperature.

There are so many air connections on the Spartan Chassis, which would seem to answer why this is possible, unless a person is keeping-up-with every fitting.

I eventually intend to check and correct each connection.

Any other advice would be welcome and helpful!

I can respond with my experience on the Gillig Air Suspension chassis Regencies. I am assuming you do not lose the air pressure to your brake system below about 65 psi. That is the safety level that is protected by an isolation valve. If you are dropping to that level you need to check the dryer valve which is the likely point of leakage. It is very rare that a connection or brake actuators are leaking but they are easy to check (Involves a mechanic using a gauge on each one). If you are experiencing a loss of the suspension system we found the dump valves to be leaking ever so slowly. On our coach there are three (we can find), one under the front passenger side behind the headlight and two in the rear engine compartment mounted on the vertical rails on either side of the engine bay. They are electrically controlled valves and they also have a ball valve with a wing nut type of knob that is open to the air. We turned them closed to test and the slow leak went away. Then we put soap on the outlet of each and saw bubbles - confirming the leaks. We are still trying to get a name and number on the valves to replace them as time and washing has removed the ink on the labels.
Hope this helps.

I had this problem when I first got my Breakaway and it has the Spartan chassis. You are right, this was discussed before.

The problem was traced to the vacuum generators that use air pressure. The vacuum is used for cruise control (one in the rear) and another used to control the actuators in the dash HVAC system. The actuators are supposed to have a regulator and cutoff that will prevent depleting the air pressure but as the actuators age, they will continue to use air until it is all gone. If there is a vacuum leak in the cruise control or dash system it will accelerate the use of air.

You may hear a slight burst of air periodically as the vacuum generators are working (engine off) but that should stop when the air pressure gets low. I could hear this outside of the coach when it was quiet.

The vacuum generator was made by/for Ford and is NLA.

What it looks like:


HTH

Well, a little update to my dilemma...after taking the Breakaway out for a couple of trips, it seems that all things are normal once again. I should state here, normal as they have been since I bought my Barth. That doesn't necessarily mean it is correct. I still loose pressure while sitting, but not like it was. After a three day outing, it still has pressure in the tanks. As stated before, once started I keep good pressure all the time with the release valves operating as they should.
Bruce

Do you drain your air tanks after you get somewhere? Even if you have an air dryer in your system you should drain the water and crud out of your tanks and keep an eye on the amount that comes out,....that will give you an idea of what kind of shape your compressor is in.

Thanks for the input. I have never done that, but guess I better at least do it once!
Bruce