AC compressor?

[Alex345]

My parents recently switched from mobile air conditioning units to a central system, of the 3 mobile units i took apart the oldest one which barely generated any cool air anymore, as it was going to be thrown out anyway. It's a small compressor but it weighed in at over 11kg's! It was basically half the weight of the unit!

I know fridge compressors are often used for spudding purposes, would this be suitable? I reckon it's much tougher as AC's are meant to run for very long times without stopping whilst a fridge comp would burn out in such a situation. But are these only more durable or do they actually provide higher pressures/faster flow too?

[jackssmirkingrevenge]

It should work, some relevant threads:

http://www.spudfiles.com/pneumatic-cann ... 18828.html

http://www.spudfiles.com/spud-cannon-re ... 17785.html

[farcticox1]

Interesting, I also have one of those as we just went to a heat pump

[Alex345]

Nice links JSR! At least now i already know that it uses a run capacitor so no need for a start up relay and that i can just remove that smaller drying cylinder as it will just get clogged with moist when i run this thing with regular air

I actually have an empty CO2 extinguisher tank sitting around here, i could build an entire high pressure mini compressor from this! Only problem is that the valve on that thing will not come loose at all... Might have to work around that. I could remove the safety burst disc and add a T-piece there for the air to enter and exit, and just keep the original "squeeze" valve in case i need to bleed off the tank. Build a nice base and frame for it with an on/off switch.

On the other hand i do like the idea of keeping that disc for in case i turn it on and forget about it... Would that comp even be able to reach pressures high enough to rupture a CO2 tank tho?

[wdr0]

I actaully use the even larger compressor from a central air unit for filling one of my cannons. It will produce 300 psi out put with 90 si in and stay under its current rating. The larger compressors will provide higher flow rates, not necessarily higher pressure. They will produce much higher pressures than their original rating but can not run long while doing so. I personally feel like these larger ones may also pass more oil than the fridge units, I have an oil filter on the outlet of mine.

[farcticox1]

So I pulled apart our old AC unit and set it up for a quick test, took my BFG up to 140 psi, not sure of the volume but probably about 2 litres, only took about 30 seconds This is going to work very nicely, going to build up a proper setup now for charging my air guns, already have an adjustable 200psi max pressure shut off switch, going to set it at about 160, safety blow off (175 psi) $2 on Ebay just need to source a regulater so I can set the output to about 140psi and need a dump valve as it doesn't like to start under load.

[wdr0]

Yeah, they do not like to start loaded, I have not tried it personally but I'd suspect a hard start kit would allow them to start loaded. It's a start capacitor and potential relay to take it out of the circuit after starting.

[farcticox1]

I'll just add a dump valve and a non return valve after it so the output is open to atmosphere when the pump is not running.