![background image](http://html1.mh-extra.com/html/carrier/weather-master-48p2/weather-master-48p2_installation-instructions-manual_2562586066.webp)
66
Table 27 — SGC Thermistor Designations
SGC
— Staged Gas Controller
Step 20 — Install Optional Motormaster
®
V
Control —
The Motormaster V control is a motor speed
control device which adjusts condenser fan motor speed in re-
sponse to varying liquid refrigerant pressure. A properly applied
Motormaster V control extends the operating range of air-condi-
tioning systems and permits operation at lower outdoor ambient
temperatures.
The optional Motormaster V controls are factory-installed.
Field-fabricated and installed wind baffles are also required for
units in areas with prevailing winds of more than 5 mph and
where temperatures drop below 32 F. The Motormaster V con-
trol permits operation of the unit to an ambient temperature of
–20 F. The control regulates the speed of one or two 3-phase fan
motors depending on unit size. Replacement of the fan motor on
most units is not necessary.
INSTALL FIELD-FABRICATED WIND BAFFLES
On size 040-060 units, in areas with prevailing winds of
more than 5 mph and where temperatures drop below 32 F,
wind baffles must be field fabricated to ensure proper cooling
cycle operation at low-ambient temperatures with Motormaster
V controls. Wind baffles are not needed on size 030, 035, and
070-100 units. See Fig. 70 for baffle details. Use 20-gage galva-
nized sheet metal, or similar corrosion-resistant material for the
baffles. Use field-supplied screws to attach baffles to unit.
Screws should be
1
/
4
-in. diameter or larger. Screws should not
be more than
1
/
2
-inch in length. Drill required screw holes for
mounting baffles.
THERMISTOR
PIN
CONNECTION
POINT
FUNCTION AND LOCATION
PART NO.
Thermistors
SAT1
J8 – 1,2 (SGC)
Supply-Air Thermistor (SAT) — Inserted into supply section
underneath the gas heat section (factory-provided,
field-installed)
HH79NZ033
SAT2
J8 – 3,4 (SGC)
Supply-Air Thermistor (SAT) — Inserted into supply section
underneath the gas heat section (factory-provided,
field-installed)
SAT3
J8 – 5,6 (SGC)
Supply-Air Thermistor (SAT) — Inserted into supply section
underneath the gas heat section (factory-provided,
field-installed)
LIMTTEMP
J8 – 15,16 (SGC)
Limit Switch Thermistor (LIMTTEMP) — Inserted next the
lower limit switch (factory-installed)
INLET
HOOD
INLET HOOD
S
IDE
INLET HOOD
S
IDE
S
CREEN
(WITH
S
PEED CLIP
S
)
a48-8473
Fig. 67 — Inlet Hood Assembly (30-in.)
Fig. 68 — Air Baffle (14-in.)
Fig. 69 — Air Baffle (30-in.)
a48-8591
a48-8590
WARNING
To avoid the possibility of electrical shock, open all discon-
nects before installing or servicing this accessory.
CAUTION
To avoid damage to refrigerant coils, electrical compo-
nents, and wiring use extreme care when drilling screw
holes and screwing in fasteners.
Summary of Contents for WEATHER MASTER 48P2
Page 10: ...10 Fig 1 Roof Curb Sizes 030 050...
Page 11: ...11 Fig 2 Roof Curb Sizes 055 060...
Page 12: ...12 Fig 3 Roof Curb Sizes 070 100...
Page 13: ...13 Fig 4 Condenser Section Roof Curb Sizes 070 and 075...
Page 14: ...14 Fig 5 Condenser Section Roof Curb Sizes 090 and 100...
Page 21: ...21 Fig 12 Base Unit Dimensional Drawing 48P2 P3030 035 Standard Chassis Unit Shown a48 8613...
Page 22: ...22 Fig 13 Base Unit Dimensional Drawing 48P4 P5030 035 Standard Chassis Unit Shown a48 8614...
Page 23: ...23 Fig 14 Base Unit Dimensional Drawing 48P2 P3040 050 Standard Chassis Unit Shown a48 8615...
Page 24: ...24 Fig 15 Base Unit Dimensional Drawing 48P4 P5040 050 Standard Chassis Unit Shown a48 8616...
Page 25: ...25 Fig 16 Base Unit Dimensional Drawing 48P2 P3055 060 Standard Chassis Unit Shown a48 8617...
Page 26: ...26 Fig 17 Base Unit Dimensional Drawing 48P4 P5055 060 Standard Chassis Unit Shown a48 8618...
Page 27: ...27 Fig 18 Base Unit Dimensional Drawing 48P2 P3070 Standard Chassis Unit Shown a48 8619...
Page 28: ...28 Fig 19 Base Unit Dimensional Drawing 48P4 P5070 Standard Chassis Unit Shown a48 8620...