Comfort-Aire TGRG Series for R-410A User Manual
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1. All wiring should be made in accordance with the National Electrical Code.
Consult the local power company to determine the availability of sufficient power to
operate the unit. Check the voltage at power supply to make sure it corresponds to
the unit’s RATED VOLTAGE REQUIREMENT. Install a branch circuit disconnect
near the rooftop, in accordance with the N.E.C., C.E.C. or local codes.
2. It is important that proper electrical power is available at the unit. Voltage should not
vary more than 10% from that stamped on the unit nameplate. On three phase units,
phases must be balanced within 3%.
3. For branch circuit wiring (main power supply to unit disconnect), the minimum wire size
for the length of run can be determined from Table 4 using the circuit ampacity found on
the unit rating plate. Use the smallest wire size allowable in Table 4 from the unit dis-
connect to unit. The disconnect must be in sight and readily accessible of the unit.
NOTES:
1. Wire size based on 60°C rated wire insulation and 30°C Ambient Temp. (86°F).
2. For more than 3 conductors in a raceway or cable, see the N.E.C. for derating the
ampacity of each conductor.
When installed, the unit must be electrically grounded in accordance with local
codes or, in the absence of local codes, with the National Electrical Code,
ANSI/NFPA 70, if an external electrical source is utilized.
IMPORTANT: THIS UNIT IS APPROVED FOR USE WITH COPPER CONDUCTORS
ONLY CONNECTED TO UNIT CONTACTOR.
WARRANTY MAY BE JEOPARDIZED IF ALUMINUM WIRE IS CONNECTED TO
UNIT CONTACTOR.
Special instructions apply for power wiring with aluminum conductors: Warranty
is void if connections are not made per instructions.
Attach a length (6” or more) of recommended size copper wire to the unit contactor ter-
minals L1 and L3 for single phase, L1, L2 and L3 for three phase.
Select the equivalent aluminum wire size from the tabulation below:
Splice copper wire pigtails to aluminum wire with U.L. recognized connectors for copper-
aluminum splices. Please exercise the following instructions very carefully to obtain a
positive and lasting connection:
1. Strip insulation from aluminum conductor.
2. Coat the stripped end of the aluminum wire with the recommended inhibitor, and
wire brush the aluminum surface through inhibitor. INHIBITORS: Brundy-Pentex “A”;
Alcoa-No. 2EJC; T & B-KPOR Shield.
3. Clean and recoat aluminum conductor with inhibitor.
4. Make the splice using the above listed wire nuts or split bolt connectors.
5. Coat the entire connection with inhibitor and wrap with electrical insulating tape.
200
6
4
4
4
3
3
2
2
150
8
6
6
4
4
4
3
3
100
10
8
8
6
6
6
4
4
50
14
12
10
10
8
8
6
6
15
20
25
30
35
40
45
50
TABLE 4
BRANCH CIRCUIT COPPER WIRE SIZE
(BASED ON 1% VOLTAGE DROP)*
SUPPLY WIRE
LENGTH-FEET
*Taken from National Electric Code
BRANCH CIRCUIT AMPACITY
AWG Copper
AWG Aluminum
Connector Type and Size
Wire Size
Wire Size
(or equivalent)
#12
#10
T & B Wire Nut
PT2
#10
# 8
T & B Wire Nut
PT3
# 8
# 6
Sherman Split Bolt
TSP6
# 6
# 4
Sherman Split Bolt
TSP4
# 4
# 2
Sherman Split Bolt
TSP2
TABLE 5
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