All of the above… built for efficiency and energy standards… problem came to light with new air handler installed.
The flow was much too high so a VFD added.
R22 is now 410a
Air is 100% outside air.
The new air handler coil is physically closer to the blower which is of a totally different design.
The preheat air handler coil was not not tied in until last week.
The pneumatic 7 zone reheats are now electric.
The Johnson Controls still not dialed in.
Several field modifications to the condenser unit such as hot gas by-pass
The new boiler was on default setting turning off… ideal for efficiency but not a process application.
Old system made 54 F air and all was good… contractor has new system making 44 F air and it sounds like it’s working hard.
The first thing I noticed is the new air handler condensate line flow is a trickle instead of a stream.
Also, several Carrier under warranty component failures such as one of the new compressors replaced, contactors, circuit board plus a defective valve vented 30 lbs of 410a
I didn’t plan to go out like this but as of this week it’s been a year project and still fighting it.
The alternative would have been 7 package units but that would have involved new electrical, altering ducting, structural engineering, building curbs, condensate lines, etc.
HVAC team said make the rooms warmer… Docs gowned up working in lead aprons or 6 hour plastics cases are not going to work at 75… truth is they would love 65 F
The weekend the new blower went in it sounded like a jet engine with static pressure of 9
Some quick action taken to reduce flow… designed for the required air exchanges of 12 requires 13,500 cfm and new unit much greater prior the VFD which is now 40% of previous volume.
Contractor always responsive but I have lost credibility with medical team…
On install weekend humidity was 78-80%