5.Set the
6.If the outdoor temperature is below 75 F, the econo- mizer will control the mixed air with the
7.Jumper terminal T to terminal T1 on the module (see Fig. 18). The economizer will go to the full open position. The
8.Adjust mechanical linkage, if necessary, for correct po- sitioning. If may be necessary to remove the ®lters to adjust the linkage.
9.Remove the jumper from around the contacts of the OAT if installed in Step 6. Remove the jumper from termi- nals T and T1 installed in Step 7.
10.If the Cooling mode was simulated to operate the unit in Step 4, remove the jumper and reconnect the ther- mostat wires to terminals Y1 and Y2.
Table 8 Ð Economizer Checkout Procedures
TEST PROCEDURE | RESULTS |
A.Disconnect power at TR and TR1. Disconnect jumper be- tween P and P1. See Fig. 18.
B.Jumper TR to 1.
C.Jumper T1 to T.
D.Disconnect
mostat connections from SO and +.
800 ohm resistor should re- main connected to SR and +.
E.Reconnect power to terminals TR and TR1.
1. LED
2. Motor is in closed position.
TEST PROCEDURE |
| RESULTS |
Disconnect |
|
|
sistor from terminals SR |
|
|
and +. | 1. | LED |
| ||
|
| should be on. |
| 2. | Motor drives toward open. |
Table 9 Ð High and Low Outdoor-Air Temperature
TEST PROCEDURE | RESULTS |
A.Reconnect
B.Connect 1200 ohm checkout
resistor between terminals SO and +.
C.Turn set point potentiometer to position A.
Low
1. LED
2. Motor drives toward open.
D.Turn set point potentiometer to position D.
E.Disconnect 1200 ohm check- out resistor.
High
1. LED should be off.
2. Motor drives toward closed.
Power Failure Ð Dampers have a spring return. In event of power failure, dampers will return to fully closed position until power is restored. Do not manually operate damper motor.
Refrigerant Charge Ð Amount of refrigerant charge is listed on unit nameplate and in Table 1. Refer to Carrier GTAC II; Module 5; Charging, Recovery, Recycling, and Rec- lamation section for charging methods and procedures.
Unit panels must be in place when unit is operating dur- ing charging procedure.
NO CHARGE Ð Use standard evacuating techniques. After evacuating system, weigh in the speci®ed amount of refrigerant (refer to Table 1).
LOW CHARGE COOLING Ð Using appropriate cooling charging chart (see Fig.
TO USE COOLING CHARGING CHART Ð Take outdoor ambient temperature and read the suction pressure gage. Re- fer to appropriate chart to determine correct suction tem- perature. If suction temperature is high, add refrigerant. If suction temperature is low, carefully reclaim some of the charge. Recheck suction pressure as charge is adjusted.
Pilot Light Ð If pilots do not light as described in Gas Heat section on page 17, be sure that pilot ori®ce is not ob- structed, then check for spark ignitor malfunctions as fol- lows:
1.Shut off control supply power to ignitor control pack (ICP).
2.Check that spark gap is 1¤8 in. 6 1¤32 inch.
3.Check that ICP is securely grounded.
4.Check that
5.Restore power to ICP. Check that 24 v is supplied to terminal TH of ICP.
6.Check unit label diagram for correct terminal usage if any wires are removed.
Fig. 33 Ð Cooling Charging Chart, 48HJ015
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