fridge compressor??

[vectraross]

anyone seen this on youtube about making a small comp out of a fridge comp? are they safe could it be made to work like a normal compressor cut out and start up again?

 

[ford34/2]

used a big pump from an industrial cold room, it looked like a 14Cu ft pump, single cylinder,ran sweet and was plumbed into an existing receiver, 150 PSI,used it for a few years till an Ingersol Rand became available. The lads in Refrigeration Services kept me right, but -- BOY that was 33 years ago!!!!

Stan

 

[rtbcomp]

Link?

Have a look here http://forums.lr4x4.com/index.php?showtopic=9710

The Clarke range of Shhhhhhhhhh compressors are fridge type compressors.

They dangerous bit is that they can develop over 200 psi, so make sure your safety valves are working!

 

[vectraross]

never thought of that 4 in tandem could fill a big tank no? i want to make one as i clean the odd carb out now n again mowers chainsaws and stuff and would be really handy,just few ive seen dont have gauges n safety valves just wandering if anyone had a clue and whats best to go for fridge or freezer compressors. wouldnt use it for blowing up bottles though....

 

[gordon stephenson]

For 40 years I had a butchers fridge/cold room compressor pump unit,only sold it a few years back to buy a higher capacity one,And before I acquired it and made a receiver it had done many years service doing it's originally intended job. Pump unit was a york shipley made in the USA, Very robust well made bit of kit, Only ever fitted one set of rings in all that time and the bores were still perfect, Could not get the correct rings so I machined the grooves a few thou wider and fitted a set of cords oil control rings, They worked even better than the originals, Here is the little fella in question after a refurb prior to selling it, (complete with tupperware sponge filled air filter)

 

[rtbcomp]

Go for freezer pumps and the biggest you can get, the starting torque of smaller units isn't very high.

Have a look in the Machine Mart catalogue, the output of the multiple units is very low.

That setup I described in the link above was used to charge multiple tanks overnight on Economy 7. They warmed the office up quite nicely too.

 

[Lawnmowerboy]

I remember reading somewhere it used the refrigerant gas to lubricate the moving parts same as a car air con system

 

[rtbcomp]

They use special oil, by the time the refrigerant gets to the pump it's a gas.

In my setup I used the cheapest thinnest engine oil I get, this is one reason why they are difficult to start. The oil gets mixed with the air and is lost so the proper stuff works out costly. You need a decent oil & water separator on the outlet too.

 

[AndyStobbs]

My main compressor at work is a modified Bock FK3 pump from a refrigerated wagon unit. I modified it to separate the oil from the air, as mentioned earlier that's the down side with A/C units. Mine has an oil pump on the back for crankshaft journals and big ends, and a rev limit of 3000 rpm. Max pressure 24bar if memory serves me.

Also made a compressor for my van by modifying an A/C compressor from a car. That wasn't as much of a success though, used to spit loads of oil out.

 

[eil]

I remember reading somewhere it used the refrigerant gas to lubricate the moving parts same as a car air con system

The gas cools the motor not lubricate it, the oil does that

 

[rtbcomp]

The oil is forced up the centre of the rotor shaft and flung around the inside of the housing, where it cools as it runs down back into bottom. It can easily reach 80 degC.

 

[dannyp]

built somethign simalar but useing a diesel powerd air con compressor, just got to build a recirculating system for the oil. a small vessel serves as a catch tank for the oil blown out the outlet then you just take a feed from the bottom of that vessel back into the intake of the compressor loose a small amount of air but keep the oil. on a fridge freezer compressor would have thought an oil trap with an autodrain may do the job

 

[rtbcomp]

The problem is the oil emulsifies. You could let it settle in a tank, but not really worth it if you use cheap Lidl oil.

 

[dannyp]

sopose a fridge isn't going to be useing much oil, th ediesel jobbie was off a wagon unit wanted a fair bit

 

[pedrobedro]

Old chap down the road used to use a fridge compressor to blow his car tyres up, it wasn't very quick and he never put any oil in it all the years I knew him and it still worked.

 

[rtbcomp]

sopose a fridge isn't going to be useing much oil, th ediesel jobbie was off a wagon unit wanted a fair bit

It's significant, I topped mine up every day or so, there's very little in there to start with.

 

[Cobbler]

I used one of those old ice cream fridge units for year's, one of the one with the 2 rubber lids that shops used to use for Lyons Maid. Used an old gas cylinder as a tank. It was ok for small jobs, tyres etc. painted a few car wings & bits & pieces. I changed the pulley sizes so it turned over quicker & it pumped to about 100psi.

 

[normspanners]

For 40 years I had a butchers fridge/cold room compressor pump unit,only sold it a few years back to buy a higher capacity one,And before I acquired it and made a receiver it had done many years service doing it's originally intended job. Pump unit was a york shipley made in the USA, Very robust well made bit of kit, Only ever fitted one set of rings in all that time and the bores were still perfect, Could not get the correct rings so I machined the grooves a few thou wider and fitted a set of cords oil control rings, They worked even better than the originals, Here is the little fella in question after a refurb prior to selling it, (complete with tupperware sponge filled air filter)

WELL I had the exact same make and style but its bigger brother about 35 yrs ago absolutely brilliant quiet but powerful the inlet air goes in the crankcase and up through the read valve in the piston.
It hardly made any water only needed to drain once a week and would easily pump to 14 bar if I wanted.

 

[Lawnmowerboy]

Where did the water go then? There will always be a standard amount of water in the air only varying with the humidity.

 

[rtbcomp]

The water is held in the hot compressed air and condenses out in the aftercooler (if fitted), tank, filter, pipework &c&c.