Rheem P16 Series Installation Instructions Manual page 36

EVACUATION AND LEAK TESTING
CHECKING REFRIGERANT CHARGE
actual charge required with installed liquid line size and
length using:
1/4" [6.4 mm] O.D. = .3 oz./ft. [8.5 g/.30 m]
5/16" [7.9 mm] O.D. = .4 oz./ft. [11.3 g/.30 m]
3/8" [9.5 mm] O.D. = .6 oz./ft. [17.0 g/.30 m]
1/2" [12.7 mm] O.D. = 1.2 oz./ft. [34.0 g/.30 m]
Add 6 oz. for fi eld-installed fi lter drier.
With an accurate scale (+/– 1 oz. [28.3 g]) or volumetric
charging device, adjust charge difference between that
shown on the unit data plate and that calculated for the
new system installation. If the entire system has been
evacuated, add the total calculated charge.
IMPORTANT:
always accurate since the application can affect the
optimum refrigerant charge. Charging by weight is con-
sidered a starting point ONLY. Always check the charge
by using the charging chart and adjust as necessary.
CHARGING BY LIQUID SUB-COOLING MUST BE
USED FOR FINAL CHARGE ADJUSTMENT.
With thermostat in the "Off" position, turn the power on
to the furnace or air handler and the heat pump. Start
the heat pump and the furnace or air handler with the
thermostat. Verify that the outdoor unit is operating in
second stage and the indoor air mover is delivering the
second-stage airfl ow for the system size.
GROSS CHARGING BY
PRESSURES
Step 1. Following air fl ow verifi cation and charge weigh
in, run the unit for a minimum of 15 minutes prior to not-
ing pressures and temperature.
IMPORTANT:
sured at the indoor coil must be within 2°F of the follow-
ing during gross charge (pressure) evaluation:
36
Charging by weight is not
Indoor conditions as mea-
Cooling Mode: 80°F Dry Bulb
Heating Mode: 70°F Dry Bulb
NOTICE:
If the Indoor temperature is above or
below this range, run the system to bring the tempera-
ture down or run the electric heat/furnace to bring the
temperature within this range. System pressure values
provided in the Charge Chart for outdoor dry bulbs cor-
responding to conditions outside of ranges listed below,
are provided as reference ONLY.
Step 2. Note the Outdoor Dry Bulb Temperature,
ODDB°F = _______°F. Unit charging is recom-
mended under the following outdoor conditions
ONLY:
Cooling Mode ONLY: 55°F outdoor dry bulb and
above
Heating Mode ONLY: Between 40°F and 60°F
outdoor dry bulb
Step 3. Locate and note the design pressures. The
correct liquid and vapor pressures are found at
the intersection of the Installed system and the
outdoor ambient temperature on the Charging
Chart located on the inside of the control box
cover of the outdoor unit.
Liquid Pressure: = ______psig; Vapor Pressure
= ______psig
NOTICE:
The refrigerant pressures provided
are for gross charge check ONLY. These pressure
values are typical, but may vary due to application.
Evaporator (indoor coil in cooling mode / outdoor coil in
heating mode) load will cause pressures to deviate. No-
tice that all systems have unique pressure curves. The
variation in the slope and value is determined by the
component selection for that indoor/outdoor matched
system. The variation from system to system seen in the
table is normal. The values listed are for the applicable
indoor coil match ONLY!
Step 4. If the measured liquid pressure is below the
listed requirement for the given outdoor and
indoor conditions, add charge. If the measured
liquid pressure is above the listed requirement
for the given Outdoor and Indoor conditions
remove charge.