Installation Manual

10
considered internal static pressure, so as long as ESP is
maintained, the unit will deliver the proper air up to the
maximum static pressure listed for the CFM required by the
application (i.e. home, building, etc.)
In general 400 CFM per ton of cooling capacity is a rule of
thumb. Some applications depending on the sensible and
latent capacity requirements may need only 350 CFM or up
to 425 CFM per ton. Check condition space load
requirements (from load calculations) and equipment
expanded ratings data to match CFM and capacity.
After unit is set and ducted, verify ESP with a 1" inclined
manometer with pitot tubes or a Magnahelic gauge and
confirm CFM to blower curves in the specification sheets.
All units have three speed blower motors. If low speed is not
utilized, the speed tap can be changed to medium or high
speed. Never run CFM below 350 CFM per ton, evaporator
freezing or poor unit performance is possible.
ADJUSTING SPEED TAP
FOR INDOOR BLOWER MOTOR
PSC Motor
Adjust the CFM for the unit by changing the speed tap of
the indoor blower motor at the EBTDR “com” connection
with one of the speed taps on “M1” or “M2”. (Black-High
Speed, Blue-Medium Speed, Red-Low Speed.)
X-13 Motor
The blower motor speed for the X-13 motor is controlled by
three 24V low voltage leads: green, yellow, and white. The
green lead sets the speed for fan-only mode. The yellow
lead sets the speed for cooling and heat pump heating
mode (if applicable). The white lead sets the speed for
electric heat mode (emergency heat and second stage
heat, if applicable).
The leads are factory connected as follows: Green to T1,
Yellow to T2, and White to T3. T1 is the low speed setting
and is dedicated to fan-only mode. T2 is medium speed
cooling and T3 is medium speed heating. T4 is high speed
cooling and T5 is high speed heating. To adjust the blower
speed, move the yellow and/or white wires to T4 and T5.
NOTE: If more than one lead is energized at the same
time, the motor will use the higher speed setting.
See CFM vs ESP tables in this manual.
SUPERHEAT CAN BE DETERMINED AS FOLLOWS:
1. Read suction pressure. Determine Saturated Suction
Temperature from tables or pressure gauge saturated
temperature scale (R-410A).
2. Read suction line temperature.
3. Use the following formula:
SUPERHEAT = SUCTION LINE TEMP - SAT. SUCTION TEMP.
Suction
Pressure
Saturated Suction
Tem
p
erature °F
PSIG R-410A
50 1
52 3
54 4
56 6
58 7
60 8
62 10
64 11
66 13
68 14
70 15
72 16
71 17
76 19
78 20
80 21
SATURATED SUCTION PRESSURE
TEMPERATURE CHART
TABLE 5
Suction Pressure Temperature (R-410A)
SUBCOOLING = SAT. LINE TEMP - LIQUID LINE TEMP.
Liquid
Pressure
Saturated Liquid
Tem
p
erature °F
PSIG R-410A
200 70
210 73
220 76
225 78
235 80
245 83
255 85
265 88
275 90
285 92
295 95
305 97
325 101
355 108
375 112
405 118
SATURATED LIQUID PRESSURE
TEMPERATURE CHART
TABLE 6
Liquid Pressure Temperature (R-410A)