Carrier 50PG20-28 Controls, Start-Up, Operation, Service And Troubleshooting Instructions page 90

CHARGING CHART (ALL CIRCUITS)
ALL OUTDOOR FANS MUST BE OPERATING
IIIIIII IIIIIIIIIIIIB,I, IIIII
IIIIIII IIIIIIUb lllllllllll
IIIIIII 134,t1111111111111111111
IIIIIII. 71111111111 ...........................
III,b IIIIIIIIIIIIIIIIIIIIIIII
Illllll IIIIIIIIIIIIIIIIIIIIIIII
II................ IIIIIIIIIIIIIIIIIIIIIIII
lse 2oo _5o 3oo }so _oo _se soo
Liquid PressuI_ oi Liquid VoEv¢, [psig]
PG2s
55o 6_o
Fig. 45 -- Charging Chart-- 48/50PG28-- Standard
Unit and Unit with Humidi-MiZer
TM
System
The TXV (thermostatic expansion valve) is set to maintain
between 10 and 15 degrees of superheat at tile compressors.
The valves are thctory set and cannot be adjusted. Do not use
an R-22 TX_
NOTE: All circuits must be running in normal cooling mode.
Indoor airflow must be within specified air quantity limits for
cooling (see Tables 27 and 28). All outdoor i_mls must be on
and running at high speed. If outdoor temperature is b,a; this
may require a temporary change in unit wiring.
TO USE THE COOLING CHARGING CHARTS, UNITS
WITH HUMIDI-MIZER ADAPTIVE DEHUMIDIFICA-
TION SYSTEM
NOTE: All circuits must be running in normal cooling mode.
Indoor airflow must be within specified air quantity limits for
cooling (see Tables 27 and 28). All outdoor l_mls must be on
and running at high speed. Use the Cooling Service Test Out-
door Fan function (Setwice Test_COOL _OEO! 0 to start all
outdoor tiros. If the outdoor temperature is lo,a; the Motonnas-
ter,¢_) o utdoor tan control device may need to be telnporarity
bypassed by rewiring the power leads to obtain full speed.
Be sure unit is in normal cooling mode by checking that the
RH2 solenoid coil(s) and the CRC relay are deeneigized
(control outputs ofl). Adjust chaise per the chaNing charts as
described in the To Use The Cooling Charging Charts,
Standard Unit section on page 89. Switch system to run in the
dehumidification mode for 5 minutes. Dehumidification 1node
is when the RH2 solenoid coil(s) and the CRC relay are
energized. Switch back to cooling 1node to recheck pressures
and temperatures on the charging chart and adjust charge if
necessary. If chaise adjustment is necessary, then repeat the
steps in this para_aph until no chaNe adjustment is necessary.
When no more charge adjustment is necessary after switching
tioln Dehumidification 1node back to Cooling mode, then
charge adjustment procedure is complete. Remove jumper
tiom the outdoor motor speed controller.
PURON@ REFRIGERANT Puron refi-igerant operates at
50 to 70 percent higher pressures than R-22. Be sure that
servicing equiplnent and replacelnent components are desiNled
to operate with Puron refrigerant. Do not mix with colnponents
that have been used with other reliigerants. Puron reiiigerant,
as with other HFCs, is only colnpatible with POE oils.
Recovery cylinder service pressure rating must be 400 psig.
Puron systems should be charged with liquid refiigerant. Use a
comlnercial-type metering device in the manifold hose. Mani-
fold sets should be 750 psig high-side and 200 psig low-side
with 520 psig tow-side retard. Use hoses with 750 psig selwice
pressure rating. Leak detectors should be designed to detect
HFC refiigerant.
Gas Valve Adjustment (48PG Only)
NATURAL GAS The gas valve opens and closes in re-
sponse to the therlnostat or limit control.
When power is supplied to vane terminals W2 (High Fire)
and C 1, the main valve opens to its preset position.
The regular factory setting is stamped on the valve body.
The setting is 3.00 in. wg for vertical supply/discharge units.
The setting is 2.95 in. wg for horizontal supply/discharge units.
To adjust regulator:
1. Set unit at setting forno call forheat.
2. Turn main gas valve to OFF position.
3. Relnove l/s-in, pipe plug tiom manifold or gas valve
pressure tap connection. Install a suitable pressure-
measuring device.
4. Set main gas valve to ON position.
5. Set thermostat at setting to call for heat.
6. Remove screw cap covering regulator adjustment screw
(See Fig. 46).
7. Turn adjustment screw cloclcwise to increase pressure or
countercloclcwise to decrease pressure.
8. Once desired pressure is established, set unit setting
for no call t\_r heat, turn off main gas valve, remove
pressure-measuring device, and replace t/8-in, pipe
plug and screw cap.
High Altitude (48PG Only) -- For high altitude appli-
cations _eater than 2000 ft the heat input rate should be
reduced. The higher the altitude is above sea level, the less
oxygen is in the air. See Table 58 for orifice sizing. A high alti-
tude kit is available to convert unit for attitudes up to 7,000 ft.
2 LEADS, #18 WIRE 1/32 INSULATION,
6OOV. MAX., 105°C
INLET PRESSURE TAP
(PLUGGED)
1/8 - 27 N.P.T. THDS.
REGULATOR
ADJUSTMENTSCREW
REMOVE COVER)
OUTLET PRESSURE
TAP (PLUGGED)
1/8-27 N.P.T. THDS.
RT O Po OL A ,NA
_ TERMINAL
"@_) '%-PILOT CONNECTION
FOR 1/4" O.D TUBING
(PLUGGED)
RECEPTACLE TERMINAL
Fig. 46 -- Gas Valve (48PG Only)
90