Remote Compressor Drain Tap

I have replaced my small noisy compressor with a larger quieter on and decided to fit a remote tap for the draining of the air receiver. The inaccessible valve on the old one always irritated but never got round to fixing it but the solution was extremely simple in the end. One swivel 1/4" BSPT elbow with 8mm push fit outlet, one 8mm push fit valve and a meter of 8mm plastic tube all from a helpful seller on ebay (cpmpneumatics) fitted in 15 minutes, should have done it years ago.

That is very good.

Just be aware though , that over time , water will get to contain more and more rust and perhaps block the ' overhead' route.

A direct blowdown now and then , just to check, is fine.

It would be pretty obvious if it became blocked but I expect blowing air through it at 100psi on a regular basis will keep it clear.

I fitted an auto drain solenoid to my compressor, it scares the bejesus out of me every time it let's rip.

Hope to move the compressor (and dust extraction unit) out of the workshop very soon into a little sub shed at the back so it had to be auto or it would never get drained.

I only drain mine every few months. How often do people do theirs?

How much water comes out on the big day? I am no expert but I believe it should be done very regularly, the manual for my compressor says weekly but I imagine it depends on usage - the point is that water sitting in there will eventually corrode the tank. I've also heard it said that it shouldn't be left with pressure in the tank when not in use so blowing down through the drain at the end of each day kills two birds with one stone.

William.

Probably a quarter of a cup full at a guess? I'll do it more often.

Why.? Just interested.

regards Martin

Couldn't say but I suppose those of a nervous disposition might consider a pressurized vessel could be a hazard. Between you and me I don't actually empty mine every night, I just crack open the valve for a second or two to blow out the condensate.

W.

I have always left mine pressured at the end of the day. Just turn off the mains. Holds pressure for some time, depends what is plugged in. Not heard of having to let down the pressure. Urban myth?

If anything I would have thought it would make it safer on the basis that you are not there 100% of the time when you leave it pressurised so if it fails it has a less than unity chance of you being there at the time. You may also add to that the repeated stress de-stress cycles may possibly increase the likelyhood of failure.

regards Martin

That is exactly what I did when the new compressor was installed at the museum. The compressor is outsise the workshop building in its own little locked up house. The hose is led inside to a ball valve and back out again to vent. The valve is at a convenient height, easy to reach and the receiver is drained every time we go home. The main three phase switch is also inside the main building. We check the oil level once a month, it never seems to use any.

If the job is easy, it will get done, if somebody had to struggle to drain the water every time, I doubt if it would.

If by chance you suffered a domestic fire involving a workshop or wherever an air compressor is sited, then the charged air reservoir would constitute an additional extra hazard to firefighters who were called out, especially if they were unaware of its presence in the premises. It's a hazardous enough job as it is.

I thought the point of the drain cock being on the bottom of the receiver was that is where the water collects. The tubing should run downhill all the way from the drain point, taking the tube up above the receiver is like a trap on a sink or toilet it will never drain completely. Tom.

While I agree that there will be some residual water in the line, it is most certainly not like the trap on a sink or toilet! Have you ever flushed the loo at 100mph? I would suggest that if the rise is substantially shorter than the initial horizontal section and the pipe is mm in diameter, not cm, all would be well.

I leave the drain cock open when the compressor is not in use. I expect a lot of the cheap items never properly drain the receiver of water, anyway.

Edited By not done it yet on 26/05/2021 14:13:17

Fire hazard ?

Plastic pipe would fail and over pressure would be relieved by safety valve.

Likely. But again, not fool-proof. Steel strength changes with temperature.

I bought a cheapo one some years ago and had to tilt it sideways slightly to drain because the drain cock was not really at the bottom!

Edited By V8Eng on 26/05/2021 14:35:26

Edited By V8Eng on 26/05/2021 14:35:59

When I bought my HPC compreessor from the local specialists they advised that the resrvoir should be stored with the drain valve open. Not only will any obvious condensation be removed, but any remaining can drain at leisure.

I blow mine down and drain after every use. The air take off is routed through a water trap / filter into a the regulator for the outlet pressure.

When professional compressed air installations are made, it usual to install take off pints from the main using four way unions. The horizontal connections are to the ring main, the upward facing one is the take off, and the downward facing ones goes to a MT cock, so that moisture can be drained off at point of use.

If the drain pipework runs upwards from the drain point on the reservoir, moisture will remain in the bottom of the pipework, and possibly in the reservoir, which defeats the purpose!

So the condensate drain should always run down, away from the reservoir.

Howard

Yes, at more than 100mph, having been considerate and not used it whilst still in the station

DaveD