Outer Limits 4x4 Board

I have searched....I know the bible backwards right now....I found a lot of information about converting A/C pumps to air compressors....but there is still two things that have me beaten.

1) I read a lot of comments about the air line getting hot...what hose should I use? And is this only said about the air line leadinf from the A/C pump to the tank, or even the hoses from the tank?

2) By the sounds of it, to do it properly (and safely) I need the following bits

Oil seperator
Non-return valve
Safety pressure relief valve
Adjustable (up and down) pressure switch
Gauge.

But have I got them in the correct place?

The heat is generated during the compression of the air, so is only needed on the compressor outlet. The air is typically expanding as it leaves the tank, so heat there isn't normally a problem.

Cheers,

Scott

thats what I was thinking...but what sort of hose should I use in that section?

Surely someone can tell me if my diagram is correct.

Diagram is fine:

On mine the non return valve and oil-seperator are around the other way (but it doesn't really matter). I ran some rubber (high-temp) air hose from the compressor outlet to the non-return valve. I originally tried normal air-line but it didn't like the heat.

Which compressor are you using. If it is a sanden type (i.e. not a york) they put out a lot of oil, so you really need a small (approx 1mm ID) capillary line from the bowl of the oil separator going back into the compressor.

Safety valve is normally mounted on the tank, as is pressure switch.

just the using the A/C pump that comes standard on HJ60's. Dont know what sort it is...but it should do the job.

G_loomis wrote:just the using the A/C pump that comes standard on HJ60's. Dont know what sort it is...but it should do the job.

Is it a horizontal barrel (cylinder) shape, or is it an upright cube sort of shape?

The former will spit a lot of oil out, so an oil return through a capillary line from the bowl of the oil trap to the compressor would be a good idea (otherwise you will be forever draining the oil trap and refilling the compressor). If it is the latter (York) type then it has a seperate sump, so doesn't lose much oil. I just check the level in my York every few weeks, and probably top it up every few months.

This is a York - with a seperate sump so it loses bugger all oil (can be modified to lose no oil).


And this is the Sanden type, which needs oil recirculation (ideally) or an oil feeder.

Safety relief valve should attatch to the tank and vent to air. It is there to prevent the tank from exploding due to over pressurisation from a malfunctioning adjustable pressure switch, or thermal expansion of the air in the tank.

Pressure switch can be put on a "T" with the safety valve if needed and switches the A/C clutch on and off. An additional remote manual switch in series with the pressure switch would be advised as a safety measure, as A/C pumps can produce far more pressure than most air tanks would handle. (second line of safety, if pressure switch and safety relief valve do not operate.)

The user air hose end from the tank should come from a seperate port on the tank, as taking it of a "T" with the pressure switch may cause the A/C pump to come on unnecessarily, possibly overpressurising the tank. It would be OK to "T" the air in/air out to the tank together.

thanks for your help guys, really appreicated!