I have refit 6 of these with revos now and a few of them if you IR tempgun the nozzles or close to it the temperature is as much as 70 degrees lower according to the temperature gun than the thermistor reports on the printer, which of course, these machines also do not extrude. Originally I thought it was nozzles jamming, not so much now.
An ideas? Planning to bring to the shop, but quietly confident it’s some kind of connection issue for the thermistor which I have, no idea how to start diagnosing.
6 ender 2 pros, 4 of them got Revo CR kits, two got piece meal assemblies (stock issue, order number #116869 if you need more details).
Stock motherboards on all machines. I am thinking it’s the splice connectors used to connect to the existing wiring as a couple of them didn’t come with the wiring from the kits, and all of them wouldn’t have had plugs for the board thermistor wise.
Interestingly it’s not happening on all of them. Originally I thought this was due to having high-flow nozzles on a couple of them, but swapping those nozzles onto other machines they still worked.
I am just going to comment on IR guns. They are very complex in fact. they are calibrated to measure dirt. (matt dark brown) The more reflective a surface is the more inaccurate (or a change to Emisifity) you can demonstrate this by putting a bit of aluminum foil and measuring that. If you put your hand over it is likely at a certain angle out will be reading you not the foil.
I might postulate the issue is the gun and not the printer. They also measure a circle and need some distance to work correctly at 1 foot most (cheap average measure 5 inches give or take. That is far too large to measure a brass nozzle.