3.14.1 GENERAL AIRFLOW OPERATING LIMITS
32
3.14.2 SELECTING INDOOR BLOWER MOTOR SPEED
The (-)H1P and (-)H1T air-handlers must be configured in the field to assure proper air-
flow is delivered for the particular application it is being used in. Refer to the AIR-FLOW
PERFORMANCE DATA in Section 3.14.3 to determine which speed tap is appropriate
for the application.
Important: The pressure drop through the required external filter is not included
in the external static pressure shown in the Air-Flow Performance Tables in
Section 3.14.3. The filter pressure drop must be added to the duct system pres-
sure drop to determine total external static pressure. Filter pressure drop increas-
es as the filter becomes dirty and must be considered when calculating worst
case external static pressure.
3.14.2.1 (-)H1P MODELS (PSC MOTOR)
(-)H1P models are designed to be matched to a specific capacity outdoor unit, 1.5, 2.0,
2.5, 3.0, 3.5, 4.0, or 5.0 tons. They have PSC motors with 2 blower motor speed taps,
low speed for applications with an external static pressure of up to 0.5” W.C. and high
speed for applications with an external static pressure above 0.5” W.C. All models are
shipped from the factory wired for high speed operation.
Note:
The external filter pres-
sure drop must be included in the external static pressure when selecting a blower
motor speed.
115V & 208/240V Models:
The speed selection is made on the Blower Control Board.
To change from high speed to low speed, remove the BLACK motor lead from the COM
terminal, remove insulated cap from the end of the RED motor lead located in the control
box and plug it into the terminal on the end of the BLACK motor lead to prevent it from
shorting to ground. Attach RED wire to the COM terminal on the Blower Control Board.
480V Models:
The speed selection is made on the Blower Relay. To change from high
speed to low speed, remove the BLACK motor lead from terminal 3 on the Blower Relay
and remove the cap from the terminal on the end of the RED motor lead. Connect the
RED motor lead to terminal 3 on the Blower Relay.
For 3-4 ton models only,
connect
the BLACK and YELLOW motor leads together.
Note:
There is no YELLOW motor lead
on 5 ton models, so plug the cap that was removed from the RED motor lead into the
terminal on the end of the BLACK motor lead to prevent it from shorting to ground.
3.14.2.2 (-)H1T MODELS (CONSTANT TORQUE ECM MOTOR)
Each (-)H1T model can be matched with 2 different outdoor unit capacities, 1.5 - 2.0
tons, 2.5 - 3.0 tons, 3.5 - 4.0 tons, & 4.0 - 5.0 tons depending on the model. (-)H1T
models have constant torque ECM motors with 5 blower motor speed taps, labeled T1
through T5. Speed selections are made on a terminal block located on the motor hous-
ing. Speed tap T1 is always dedicated to continuous fan operation and delivers approxi-
mately 50% of the speed tap T4 air-flow. Speed taps T2 & T4 are for applications with
an external static pressure up to 0.5” W.C. (speed tap T2 for lower tonnage & speed tap
T4 for higher tonnage). Speed taps T3 & T5 are for applications with an external static
pressure above 0.5” W.C. (speed tap T3 for lower tonnage & speed tap T5 for higher
tonnage). All models are shipped from the factory with speed tap T5 selected except for
the (-)H1T4824S which is shipped with speed tap T3 selected. For optimum perfor-
mance, efficiency, dehumidification, and the lowest possible noise level, select the
appropriate speed tap for the specific application at the time of installation.
Note:
The
external filter pressure drop must be included in the external static pressure when
selecting a blower motor speed.
To change the indoor blower speed on (-)H1T air-handlers, move the BLUE wire con-
nected to terminal T5 (or T3 on (-)H1T4824S) located on the motor housing to the
appropriate terminal (T2 – T5) on the same terminal block.
Cabinet Width 17 17/21 21
24
Cooling BTUH x 1,000 18 24 30 36 42 48 60
0
Cooling Tons Nominal 1.5 2 2.5 3 3.5 4 5 4
Heat Pump or Air Conditioning
Maximum Heat/Cool CFM [L/s] 675 900 1125 1350 1575 1800 1925 1800
(37.5 CFM [18 L/s]/1,000 BTUH) [319] [425] [531] [637] [743] [850] [907]
1]
(450 CFM [212 L/s]/Ton Nominal)
Heat Pump or Air Conditioning
Nominal Heat/Cool CFM [L/s] 600 800 1000 1200 1400 1600 1750 1600
(33.3 CFM [16 L/s]/1,000 BTUH) [283] [378] [472] [566] [661] [755] [826] [755]
(400 CFM [189 L/s]/Ton Nominal)
Heat Pump or Air Conditioning
Minimum Heat/Cool CFM [L/s] 540 720 900 1080 1260 1440 1575 1440
(30.0 CFM [14 L/s]/1,000 BTUH) [255] [340] [425] [510] [595] [680] [743] [680]
(360 CFM [170 L/s]/Ton Nominal)
Maximum kW Electric Heating 13 13 18 18 20 25 25 25
& Minimum Electric Heat CFM [L/s] 487 [230] 617 [291] 814 [384] 1054 [497] 1171 [553] 1502 [709] 1502 [709] 1502 [709]
]
Maximum Electric Heat Rise °F [°C] 80 [26.7] 63 [17.2] 66 [18.9] 51 [10.6] 49 [9.4] 50 [10] 50 [10]
6
5
1930*
[91
1800*
[850]
1620*
[765]
1666 [786
54 [12.2]
[850]
50 [10]
48
*CFM [L/s] per ton requirements are
reduced for 5 ton systems.
