Many companies turn tbeir a/c...heaters off when closed. Come to work freezing. Tirn heat and expecting the heater to warm up the place in minutes. When it takes a few hours to warm up the WHOLE building and everything in it.
On those types of calls I always start looking at the gas regulator to see if the vent is iced up or plugged. So many times I have found that was the issue
*It would have been nice to see you cover up that factory punched hole you can see just after **1:15** in the lower bottom right hand side of the paneI with 3 or 4 layers of metallic seam tape, because that's probably where the bird was coming in from.*
Don't lie.. you didn't miss us... you big faker. Thats a beat down york unit. Maybe the line had to get bled out of air.Keep it running till the new year when equipment becomes available. Stay safe and be well