COMPRESSOR TALK

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Boo Cock
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COMPRESSOR TALK

Post by Boo Cock »

It's a long shot, but maybe someone here knows what to do. I have a compressor, a FIAC 50 litre Miami. The problem is, it will not switch off when it reaches full pressure. So, if I switch it off at the control switch, then empty some air out, the motor cuts in again, but will not turn over. I have to give it a shove on the flywheel. Then off it goes again and the same thing happens again. Is it the switch that needs adjusting or is it the pressure sensor, or whatever? Can ahyone shed some light on this?
special one
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Re: COMPRESSOR TALK

Post by special one »

My compressor does similar, it won't switch off then the prd kicks in, I think my switch just needs taking apart, cleaning and oiling.
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Treadtrader
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Re: COMPRESSOR TALK

Post by Treadtrader »

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Boo Cock
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Re: COMPRESSOR TALK

Post by Boo Cock »

Seen that lot on E Bay. Although it sounds good, it also sounds too good. Switches are normally around the £100 mark for mine. Sounds a bit too good. Anyone had any dealings with these items? Switch on mine is a Condor MDR 2/EA/11 11BAR/1100kpa. Means very little to me but someone must know what it's all about!
chopper_harris
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Re: COMPRESSOR TALK

Post by chopper_harris »

FIAC compressors are the budget models imported by Wilkinson Star in Manchester.
The Miami 50 is a small hobby model, built using low-cost components.

Why would a low-spec £200 compressor be fitted with a £100 pressure switch ?

I would spend a little more and go for a replacement switch from Machinemart :

https://www.machinemart.co.uk/shop/prod ... mp-3-phase


Image

For £20 you get face-face advice on fitting, plus local support in case of future issues.
Boo Cock
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Re: COMPRESSOR TALK

Post by Boo Cock »

Got a new switch this weekend, fitted easy enough, it will now cut out, but a bit too late I think at 150 PSI. It does not blow off when it cuts out and will not turn over (without a push) when the pressure is let off. There is a valve on the top where it feeds from the cylinders to the tank, is this suspect? Any ideas anyone????????
akendall1966
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COMPRESSOR TALK

Post by akendall1966 »

There should be a non return valve at the point the pipe enters the tank. When the switch cuts out it should dump the pressure between the compressor and that check valve so there is no load on the motor when it starts up. May be that check valve is leaking so the motor cannot overcome the pressure in the pipe.
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bowber
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Re: COMPRESSOR TALK

Post by bowber »

While the switch is off there is a valve open on the bottom, this should be connected to the compressor to bleed off the pressure from the compressor side of the one way valve, it stays open all the time the switch is off so any leakage past the one way valve would leak out anyway.

So is the relief valve on the switch connected?

More expensive compressors used to have a centrifugally operated valve but these days I only see the relief valve operated ones.

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videoman
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Re: COMPRESSOR TALK

Post by videoman »

Usually when the compressor will not start up when it is under pressure the pressure relief valve is at fault. If you look for a pipe which goes from the compressor pump to the receiver you will see a fitting screwed into the receiver with a large nut on top. Make sure the receiver is empty and remove nut, then you should find a spring and rubber washer and usually the spring has broken or the rubber washer excessively worn allowing air back into the compressor pump which makes starting almost impossible.

I used to work in a previous life as a service engineer installing and maintaining vehicle lifts, compressors and all aspects of garage equipment, dirty heavy work but it paid the bills.
Boo Cock
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Re: COMPRESSOR TALK

Post by Boo Cock »

Got the little bugger sorted now. It was cheaper to get a new one than it was to repair. Chineese crap! :unsure:
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