Check Charge - Bryant Base Series Application Manual And Service Manual

Residential Air Conditioners and Heat Pumps Using R-22 and Puron® Refrigerant: Application Guideline and Service Manual
Triple Evacuation Method
The triple evacuation method should be used when vacuum pump is only
capable of pumping down to 28 in. of mercury vacuum and system does
not contain any liquid water. Refer to
1. Pump system down to 28 in. of mercury and allow pump to
continue operating for an additional 15 minutes.
2. Close service valves and shut off vacuum pump.
3. Connect a nitrogen cylinder and regulator to system and open until
system pressure is 2 psig.
4. Close service valve and allow system to stand for 1 hr. During this
time, dry nitrogen will be able to diffuse throughout the system
absorbing moisture.
5. Repeat this procedure as indicated in
free of any contaminants and water vapor.
EVACUATE
BREAK VACUUM WITH DRY NITROGEN
EVACUATE
BREAK VACUUM WITH DRY NITROGEN
EVACUATE
CHECK FOR TIGHT, DRY SYSTEM
(IF IT HOLDS DEEP VACUUM)
CHARGE SYSTEM
Fig. 36 – Triple Evacuation Method
Manufacturer reserves the right to change, at any time, specifications and designs without notice and without obligations.
Fig. 36 and proceed as follows:
Fig. 36. System will then be
WAIT
WAIT

Check Charge

(See Charging Table 11
Factory charge amount and desired subcooling are shown on unit rating
plate. Charging method is shown on information plate inside unit. To
properly check or adjust charge, conditions must be favorable for
subcooling charging. Favorable conditions exist when the outdoor
temperature is between 70°F/21.11°C and 100°F/37.78°C, and the
indoor temperature is between 70°F/21.11°C and 80°F/26.67°C. Follow
the procedure below:
Unit is factory charged for 15ft (4.57 m) of lineset. Adjust charge by
adding or removing 0.6 oz/ft of 3/8 liquid line above or below 15ft (4.57
m) respectively.
For standard refrigerant line lengths (80 ft/24.38 m or less), allow system
to operate in cooling mode at least 15 minutes. If conditions are
favorable, check system charge by subcooling method. If any adjustment
is necessary, adjust charge slowly and allow system to operate for 15
minutes to stabilize before declaring a properly charged system.
If the indoor temperature is above 80°F /26.67°C, and the outdoor
temperature is in the favorable range, adjust system charge by weight
based on line length and allow the indoor temperature to drop to 80°F
(26.67°C) before attempting to check system charge by subcooling
method as described above.
If the indoor temperature is below 70°F / 21.11°C, or the outdoor
temperature is not in the favorable range, adjust charge for line set length
above or below 15ft (4.57 m) only. Charge level should then be
appropriate for the system to achieve rated capacity. The charge level
could then be checked at another time when the both indoor and outdoor
temperatures are in a more favorable range.
NOTE: If line length is beyond 80 ft (24.38 m) or greater than 20 ft
(6.10 m) vertical separation, See Long Line Guideline for special
charging requirements.
A95425
36
& Table 13)