Carrier WEATHERMAKER 50TFQ008, Инструкция по установке, запуску и обслуживанию

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Manufacturer reserves the right to discontinue, or change at any time, specifications or designs without notice and without incurring obligations.
Catalog No. 005-052 Printed in U.S.A. Form 50TFQ-C2SI Pg 26 11-00 Replaces: New Book 1 4
Tab 5a 5a
Copyright 2000 Carrier Corporation
Table 17 — Durablade Economizer Troubleshooting
LEGEND
PROBLEM CAUSE REMEDY
Damper does not
open.
Indoor fan is off. 1. Check to ensure that 24 vac is present at terminal C1 on the IFC or that 24 vac is
present at the IFO terminal. Check whether 24 vac is present at PL6-1 (red wire)
and/or PL6-3 (black wire). If 24 vac is not present, check wiring (see unit label
diagram).
2. Check proper thermostat connection to G on the connection board.
No power to economizer
motor. 1. Check that SW3 is properly making contact with the damper blade. Check that
SW1 is in the NC (normally closed) position.
2. Check diode D18. If diode is not functioning properly, replace economizer control board.
3. Confirm that the economizer control board is grounded properly at PL6-4 (brown
wire) and at brown terminal of the economizer control board (brown wire). The
economizer motor must also be grounded properly at the negative motor terminal
(brown wire).
4. Verify SW1 and SW3 are working and wired properly (see unit label diagram).
5. Check for 24 vac input at both PL6-1 (red wire) and PL6-3 (black wire). If 24 vac
not present, check unit wiring (see unit label diagram). If 24 vac is found in both
places, check for 24 vac at the yellow terminal of the economizer control board
(yellow wire). If 24 vac power is not present, replace the economizer control board.
Economizer motor failure. If the indoor fan and economizer motor are energized, verify that there is a minimum
of 18 vdc at the positive motor terminal. If the motor is not operating, replace the
motor.
Economizer
operation
limited to minimum
position. OAT or EC set too high. 1. Set at correct temperature (3 F [–16.1 C]) below indoor space temperature).
2. Check OAT or EC by setting above outdoor temperature or humidity level. If the
OAT or EC switches do not close, replace OAT or EC.
Economizer control board
incorrectly wired or not
functioning. 1. Perform the following tests when OAT or EC is closed. Y1 is called for, and damper
is at minimum position. Confirm 24 vac on gray terminal of the economizer control
board (gray wire). If 24 vac is not present, check wiring (see unit label diagram).
2. Verify that SW1 and SW3 are wired correctly and working properly (see unit label
diagram).
3. Check to ensure that 24 vac exists at PL6-2 (blue wire). If 24 vac is not present,
check wiring (see unit wiring label diagram).
4. Check 24 vac output at PL6-10 (white wire). If 24 vac is not present, replace
economizer control board.
Incorrect SAT wiring or
inoperative SAT. 1. After verifying that the OAT and EC settings and the economizer control board wir-
ing are correct, check to ensure that the 24 vac terminal of the SAT has 24 vac
(white wire). If OAT, EC, and control board are functioning and wired properly and
no 24 vac exists, check wiring (see unit label diagram).
2. If supply-air temperature is greater than 57 F, 24 vac should be found at terminal
T2 on the SAT (pink wire). If 24 vac is not present, replace SAT.
Damper does not
close. Incorrect economizer
wiring. 1. Verify that SW2 and SW4 are wired and working properly (see unit label diagram).
2. Check diode D19. If diode is not functioning properly, replace economizer control board.
Incorrect damper actuator
wiring or inoperative
economizer circuit board. 1. After verifying that the wiring is correct, modulate the damper to the minimum posi-
tion. Remove the calls for G.
2. If the damper does not move, check for 24 vac at PL6-1 (red wire). If 24 vac is not
present, check wiring (see unit label diagram).
3. If damper still does not move, check for 24 vac at blue terminal of economizer con-
trol board (blue wire). If 24 vac is not present, replace the economizer control board.
Incorrect SAT wiring or
inoperative SAT. 1. After verifying that the wiring is correct and the economizer control board is func-
tioning properly, place the OAT or EC switch in the closed position. Place a call for
Y1 and open the damper to the fully open position. Confirm that the 24 vac terminal
of the SAT has 24 vac (white wire). If 24 vac is not present, check wiring (see unit
label diagram).
2. If supply-air temperature is less than 52 F, 24 vac should be found at terminal T1
on the SAT (violet wire). If 24 vac not found, replace SAT.
Economizer motor failure. If economizer control board and SAT are functioning properly, verify that there is a
minimum of 18 vdc at the positive motor terminal. If a minimum of 18 vdc is present
and the motor is still not operating, replace the motor.
Economizer damper
does not close on
power loss. Insufficient battery power,
inoperative economizer
control board. 1. Check voltage potential across batteries. If lower than 14 vdc, replace close-on-
power-loss power supply (9-v alkaline batteries). Check this emergency power sup-
ply on a regular basis or whenever the filters are changed.
2. If the close-on-power-loss and economizer control board are functioning properly,
check for 14 vdc or higher at the blue terminal of the economizer control board
(blue wire) when power is disconnected from unit. If 14 vdc is not present, replace
the control board.
C1 — Common Power
EC — Enthalpy Control
IFC — Indoor Fan Contactor
IFO — Indoor Fan On
OAT — Outdoor-Air Thermostat
PL — Plug
SAT — Supply-Air Thermostat
SW — Economizer Position Switch