HONEYWELL ZONE PROBLEMS

[MAC AIR]

I have a question about a unit installed with honeywell zone. Unit is shutting off due to dats causing cool light to blink and compressor to cycle.
The system has bypass damper, but with no weight . as far as I know it has always been like that and worked fine. I haven't spent a lot of time on this issue yet. But I thought I would post and get some ideas.
When I was on sight I noticed that the bypass to touch was ice cold. I disconnected dats temporarily to allow unit to run with out cycling off. but I am worried about evap icing up. Maybe dats is bad I don't know Another thing when I opened panel on furnace alot of rat poop i meen a lot. I am worried that it is possible that maybe the rats ate thru ductwork. Going back to add weight to bypass. But any ideas would help thank you

[B1978]

check the charge, set the bypass to factory specs.