Bryant Evolution Extreme 191VAN - Step 12 - Pumpdown & Evacuation

191VAN Evolution™ Extreme Variable Speed Air Conditioner: Installation Instructions
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
13
Step 12 – Pumpdown & Evacuation
Because this system has a VFD controlled compressor the conventional
procedure cannot be used to "pumpdown" and isolate the refrigerant into
the outdoor unit. The Evolution™ Connex™ System Control has
provisions to assist in performing this function.
1. Connect gauges to liquid and vapor or suction capillary service
ports to monitor operating pressures during and at completion of the
procedure.
2. In the "installation and service" menu of the Evolution™ Connex™
System Control (see Fig. 12), go to “refrigerant charging” and then
“pumpdown” (see Fig. 13 and Fig. 22).
3. Pumpdown in COOL mode allows refrigerant to be isolated in
outdoor unit. Set desired time period. Default time period for the
procedure is 20 minutes. See Fig. 23.
4. Select Start on Evolution™ Connex™ System Control to begin the
pumpdown process. Unit will begin running in cooling mode after
a brief delay and a status screen will be displayed. See Fig. 24.
5. Close the liquid service valve.
6. The unit will run with the low pressure protection set to indicate
pumpdown is complete when the suction pressure drops below 20
psig. Compressor protections are still active to prevent damage to
the compressor or VFD (high pressure, high current, etc.).
7. Once system indicates pumpdown complete or failure to complete
shutdown, close vapor service valve.
8. A recovery system will be required to remove final quantity of
refrigerant from indoor coil and line set. Refer to Service Manual
for specific evacuation and purge steps required after recovering
refrigerant and before making any repairs to the indoor unit or
lineset.
9. Remove power from indoor and outdoor unit prior to servicing unit.
A240378
Fig. 22 – Pumpdown and Evacuation Selection
A240342
Fig. 23 – Pumpdown Setup Screen
A240354
Fig. 24 – Pumpdown Active Screen