10

Table 1 — Physical Data (cont)

LEGEND
*The ZRU140KC compressor is a tandem compressor, consisting of a ZR72KC (25% total
capacity) and a ZR68KC (24% total capacity).
†Circuit 1 uses the lower portion of the condenser coil and lower portion of the evaporator
coils; and Circuit 2 uses the upper portion of both coils.
**Pulley has 6 turns. Due to belt and pulley size, movable pulley cannot be set to 0 to 11/2
turns open.
††Pulley has 6 turns. Due to belt and pulley size, movable pulley cannot be set to 0 to 1/2turns
open.
***Rollout switch is manual reset.
†††A Liquid Propane kit is available as an accessory.
¶The 48TM028 unit requires 2-in. industrial-grade filters capable of handling face velocities up
to 625 ft/min (such as American Air Filter no. 5700 or equivalent).
NOTE: The 48TM016-028 units have a low-pressure switch (standard) located on the suction
side.
UNIT 48TM 016D/F 020D/F 025D/F 028D/F
FURNACE SECTION
Rollout Switch Cutout Temp (F)*** 190 190 190 190
Burner Orifice Diameter (in. ...drill size)
Natural Gas Std 0.1285...30/0.136...29 0.1285...30/0.136...29 0.1285...30/0.136...29 0.1285...30/0.136...29
Thermostat Heat Anticipator Setting (amps)
208/230, 575 v Stage 1 0.98 0.98 0.98 0.98
Stage 2 0.44 0.44 0.44 0.44
460 v Stage 1 0.80 0.80 0.80 0.80
Stage 2 0.44 0.44 0.44 0.44
Gas Input Stage 1 172,000/225,000 206,000/270,000 206,000/270,000 206,000/270,000
Stage 2 230,000/300,000 275,000/360,000 275,000/360,000 275,000/360,000
Efficiency (Steady-State) (%) 81 81 81 81
Temperature Rise Range 15-45/20-50 15-45/20-50 15-45/20-50 15-45/20-50
Manifold Pressure (in. wg)
Natural Gas Std 3.3 3.3 3.3 3.3
Liquid Propane††† Alt 3.3 3.3 3.3 3.3
Gas Valve Quantity 1111
Gas Valve Pressure Range
in. wg 5.5-13.5 5.5-13.5 5.5-13.5 5.5-13.5
psig 0.235-0.487 0.235-0.487 0.235-0.487 0.235-0.487
Field Gas Connection Size (in.-FPT) 3/43/43/43/4
HIGH-PRESSURE SWITCH (psig)
Cutout 426
Reset (Auto) 320
LOW-PRESSURE SWITCH (psig)
Cutout 27
Reset (Auto) 44
FREEZE PROTECTION THERMOSTAT (F)
Opens 30 ± 5
Closes 45 ± 5
OUTDOOR-AIR INLET SCREENS Cleanable
Quantity...Size (in.) 2...20 x 25 x 1
1...20 x 20 x 1
RETURN-AIR FILTERS Throwaway
Quantity...Size (in.) 4...20 x 20 x 2
4...16 x20 x 2
POWER EXHAUST 1/2Hp, 208/230-460 v Motor Direct Drive, Propeller-Fan (Factory-Wired for 460 v)
Bhp — Brake Horsepower
TXV — Thermostatic Expansion Valve