I posted my troubles on the ExPo forum, seeing as they aren't specifically MV-related, but maybe someone has walked a mile in my shoes on this forum.
Chinese hydronic diesel heater-
this one specifically.
It's installed and bled reasonably well. Heat cycle starts, pump kicks on briefly, and then would cut out and error the controller, so I hard wired the pump with its own 12v supply. Things started to run well, and the whole process begins and makes progress until 15-18 minutes, where it gets to ~62°C and then shuts down. Flashes an error of E-14, and entertainingly enough, the trouble shooting guide skips -14 and -15.
There is a tech support email address but so far no response.
On one hand, this was going to be a ~$250 gamble and I may just move on to the high $ Euro brand, but the furnace fires up and seems to do well enough heating the the glycol that it seems dumb to spend ~$2k if there's just something small I am missing. Anyone seen this before? Any good ideas to work around it?