Evap fin spacing and freezeup

[Bigfreeze]

Bigfreeze, I have always wanted to make my own tanks but we cannot manufacture custom tanks here and have them accepted by authorities unless they meet ASME rules and a 500L tank, for example, would need 1/4" steel and be welded by a certified pressure vessel welder and inspected. This tank would cost 3 times the european version.
Correct me if I am wrong but in Europe you can build a tank, meet the pressure test standards (self tested) and sell the thing (with a rating based on your testing). Over the years the regs there have kept up with the advances in alloys etc so that that same 500L tank that needs 1/4" steel here could be make with 1/8" steel there. Our regs have not kept up with the same advances. Here is a real world example: I visited the Viessmann plant in Germany 10 years ago. They were complaining that the flange for one of condensing boilers needed to be 25mm for North america where in Europe it was 12mm and the max pressure rating for the same boiler was 2 bar here and 5 bar in europe. This mentality is pervasive here and it is one reason why so many companies don't bring all their products here. I know I am a bit .

You need your products to be tested to european standards here too. Its not cheap. In the middle of that very process myself. Developing a tank to work in conjunction with heat pumps. A steel pressurised tank would be expected to be rated a 6 bar at 70C

[Bigfreeze]

Mike, are you going for a package unit outside (evap, compressor etc) or leaning towards a split model with evap outside and the rest inside?