[AC_Hacker]

NiHaoMike,

Originally Posted by NiHaoMike

Sam's Laser FAQ - Vacuum Technology for Home-Built Gas Lasers
I don't have a gauge that can precisely measure the vacuum level, but it pulls as low as the gauge set will measure. I estimate 1 Torr or so since it is a rotary compressor.

Thanks for the link to the laser/vacuum page. Lots of very good info there.

However, in the section on using refrigeration compressors, it stated:

Almost any real vacuum pump (including refrigeration service types) - even one that has been neglected and abused - will pull a better vacuum than most refrigeration compressors

So, in my opinion, for the purposes of experimentation, a refrig/freezer/de-humidifier compressor would be just fine to test out the technology.

But the purpose of this thread is enable you to build your own highly reliable, very economical Ground Source Heat Pump for your home. A properly built heat pump should last decades. And since refrigeration reliability is very much dependant on purging your system of any water, for the final version of your heat pump, you might want to get pretty serious about the vacuum thing (known good vacuum pump, known good micrometer vacuum gauge, strict adherence to proper procedure, no short-cuts).

As I have gone through this saga of learning all I can about GSHP technology and coming to grips with all the sub-technologies associated with it, my standard of comparison is a $35,000 GSHP system with a COP of 3.5. If I can approach that performance for a tiny fraction of the cost (I'm still shooting for a final cost of under $1000), then I have completely succeeded.

Regards,

-AC_Hacker

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