Hello,

I was hoping to get some input on an issue with our furnace/heat-pump unit. Basically it has lost the ability to keep our house cool, we have had 2 HVAC professionals come out to look at it with no resolution thus far. Below are some details on our house, our unit, the fault behavior, and what has been tried:

About our house:
• 2-Story Colonial
• Located in Metro-Detroit Michigan area

About our A/C unit (installed in 2007):
• Thermostat = Bryant Evolution
• Software Version = CESR131339-14
• Furnace = Bryant 355AV0420
• Heat Pump = Bryant 286ANA036

Timeline
• First observed this near the end of the cooling season in 2019 (wasn't motivated to fix at the time)
• Continued observing this into the start of the 2020 cooling season (delayed starting to look into this due to COVID)

We have observed the following faults:
• 84-High pressure lockout 4 hours
• 83-Low pressure lockout 4 hours

Fault behavior:
• Unit will put out cold air for a period of time, varying from 15 minutes to a couple hours
• After this, the unit will stop putting out cold air and one of the above fault codes will appear

What we have tried (no improvement with any of these):
• Replaced a motor capacitor
• Cleaned condenser coils
• Replaced air filter
• Checked freon levels (Normal)
• Open/closed air outputs on 1st floor (in the summer months we like to keep the 1st floor closed up so more cold air makes it upstairs)

Please let me know if any additional information is needed, and I can follow up.

If anyone has any ideas on what is causing this, please let me know, it would be greatly appreciated.

Thanks!