@ AMI Contracting: Measurments taken with factory installed sensors. LT1 not easy to measure with external probe. GPM measured with the drop out line, so it's accurate both on flow and temperature. There are no lock outs, the freezing protection has been cut and a flow switch installed to ensure that no flow = no compressor. It's hard to have an installer drive 2 hours to check what might no even be a problem, we always end up with 1000$ bill when someone comes, so yoou will understand we do as much as we can by ourselves. The warranty is limited in my case since I opperate at the boundaries of ClimateMaster Open Loop specs. With all my experiements, I find their numbers are too conservative but I don't bother arguing that with them. The fact is that the system is working, I might not like the numbers but it is working. Cheers, Laurence.