testing first phase cooler

[mr-white]

ive just got round to testing my cooler. im using 1/4hp compressor, baker block and gonna use propane as the refrigerant. pic here (http://www.b0rich.fast24.co.uk/cooler/rebuilt%20004.JPG). the thing is when i turn it on the pressure slowly goes off the scale pic here (http://www.b0rich.fast24.co.uk/cooler/rebuilt%20002.JPG). the blue dial is connected to the high side. i know i have 2 very small holes i need to plug but should the pressure go straight to max (10 bar) ?

MW

[froudeg]

Right, firstly you should be using the red guage to measure high side pressures. With gases such as propane and r404a - high side pressures can be as high as 250 psi (altho around 170-220 psi is the norm for r404a).

Secondly - get the holes sorted, with pressures such as these even a hole the size of a needle point is enuf to empty the gas out of your system pretty quickly.

I also hope to god your not trying to power the system up with just air in it! - if you want to test for leaks - see if it can hold a vacuum first.

[Pandrone]

Blue= Lowside
Red= Highside

[mr-white]

thanks ill give it another go when it stops raining

was planning on filling the holes, had already filled a few just 2 small ones left when i thought about the pressure in the system

what happens if its powered on with just air in ?

MW

[craig588]

You will burn out the compressor

[mr-white]

ah have only done it a few times for literally 20s a time.

MW

[Chris_F]

Never run a compressor with air in it. They arn't powerfull enough to compress air.

[mr-white]

is it ok to run it once its been vacuumed ?

would a 1/12hp compressor be ok to vacuum the system ?

MW

[Epsilon]

Small addition:

Make a coil in the discharge line. When the compressor starts, it shakes a little bit. The way you have piped your discharge line, the joint on the condenser will take the full blow. It will break eventually.