How often do you drain the front and rear air tanks?

[Gyrophoenix]

From the Owners Manual: "Drain the front and rear air tanks once a month or more depending on operating conditions and humidity levels."

What's your experience? Is it really needed once a month?

Thanks.

 

[Rene T]

From the Owners Manual: "Drain the front and rear air tanks once a month or more depending on operating conditions and humidity levels."

What's your experience? Is it really needed once a month?

Thanks.

I would try it the first month and record how much came out. Then try going for 2 months and compare the two. Then try 3 months and compare. Now this will work if you rv in the same area.
If you travel in a high humidity area, you will have to start over.

 

[Gyrophoenix]

Well... I'm fairly OCD about maintenance, but draining the tanks is an item I overlooked. This morning I drained the tanks for the first time in about 2 years, and NO moisture came out. None. I left them open for about a minute each, and didn't see any moisture at all. The air dryer must be doing a great job.

 

[Larry N.]

This morning I drained the tanks for the first time in about 2 years, and NO moisture came out. None. I left them open for about a minute each, and didn't see any moisture at all. The air dryer must be doing a great job.

I found the same as you did in both of my diesel coaches- never in 12 years did I find any water to drain.

 

[Gary RV_Wizard]

If you keep the air dryer serviced on the recommended schedule, you should never have any water in the air tanks. The only way to prove that, though, is to sample the tanks occasionally. Drain the tanks, install a new air dryer cartridge, and then drain again after a few thousand miles of travel. If you get any water, use a shorter drain interval. If no water, a longer interval.

 

[Gyrophoenix]

Thanks to all!

 

[Lou Schneider]

If there's condensed moisture in your tanks it will show up as soon as you open the drain valve. When it stops you can close the valve and let the remaining pressure remain in the tank. We would drain the air tanks at the end of every day at the trolley museum to get rid of the accumulated moisture at the bottom of the tanks (the cars had railroad type air brakes without air dryers). The drain valves were just cracked open, as one instructor put it there's no need to re-arrange the track ballast under the tanks. When the water stopped pouring out we closed the valve and let the remaining pressure stay in the tank.

 

[Gary RV_Wizard]

Good point, Lou. Drain the water, not the air!

 

[RayIN]

Well... I'm fairly OCD about maintenance, but draining the tanks is an item I overlooked. This morning I drained the tanks for the first time in about 2 years, and NO moisture came out. None. I left them open for about a minute each, and didn't see any moisture at all. The air dryer must be doing a great job.

Is there automatic moisture drains on your tanks too? FWIW, the air dryer dessicant filter should be replaced every 2 years on a MH. It also filters out compressor oil, and cannot be purged like water.

 

[Gyrophoenix]

Is there automatic moisture drains on your tanks too? FWIW, the air dryer dessicant filter should be replaced every 2 years on a MH. It also filters out compressor oil, and cannot be purged like water.

I don't think there are any automatic drains. The manual makes no mention of them, only advising to drain the tanks once a month, which seems to be a bit too often, at least for my coach. The desiccant filter is changed regularly.

 

[RayIN]

Often automatic tank drains are an option. If you have them, they would fit in a 4"sq box, and the manual drain is incorporated into it, with a cable attached.
Without automatic drains the manual drain is screwed into the tank. I think both have 3/8" pipe threads.
Anyway, If you hear air escaping from the manual drains, they are working as designed.
Given the importance of eliminating water from the compressed air, pulling the drain cables inconvenience is quite minor IMO.
If water/moisture ever gets into the braking system it's $$$$$.