I have a small freeze dryer with a single stage R-404a compressor that can not handle the hot, humid climate in Thailand. The best it can do is get down to -33°C, which is not cold enough to act as a cold trap for freeze drying. It needs to cool to -45°C in order to be useful. I would like to convert the cooling system into a 2 stage design by replacing the existing condensor with a heat exchanger, and running a second R-134a refrigerant system through it that keeps the R-404a output on that heat exchanger at approximately 10°C.

 

I am looking for someone who can help me create an appropriate, cost effective design and assist me in building the system.

 

any schematics? data sheets? info about where the system is located?

4 hours ago, codebunny said:

any schematics? data sheets? info about where the system is located?

System is located in the suburbs of Northern Bangkok. No schematics or datasheets. This would be a trial and error solution.

 

 

You mean like Rangsit and round there?

Trial and error sounds a bit expensive, I guess you have already run the idea past people and got some idea of what you need, where you get it from, and perhaps a manufacturer website to get info from?

Yes. The unit is very near Rangsit. I do have an idea of what to do, but little experience an no idea of what I don't know. Most of it can fabricated from copper tubing and should be available locally or through the mail order services. This is essentially a back yard retrofit in order to increase the cooling capacity.