13
INSTALLER’S GUIDE
18-HE39D8-13A-EN
5A. Checkout - For Units with a Honeywell W7459 Control, Only.
See 5B for W7212
SINGLE ENTHALPY CHANGEOVER SET POINT
Single enthalpy:
The enthalpy changeover set
point is set to return the outdoor air damper to
minimum position when the
enthalpy rises above its set point. The enthalpy
set point scale markings, located on W7459,
are A,B,C,D; see table for the corresponding
control point. The factory-installed R4 WHITE
620-ohm jumper must be in place across ter-
and SR.
Operate the motor through its complete open-close stroke.
If necessary, release one of the previously tightened linkage
connections to prevent damage. Check for proper operation,
making sure that the linkage does not bind and that the motor
travels smoothly throughout its fully open and closed position.
Table 1 describes how to drive the motor to the full open and full
closed positions (power connected). If there is excess length of
linkage rod, cut it to size. Make necessary minor adjustments until
desired operation is obtained, and tighten all nuts and set screws.
This motor checkout ensures that:
1. The motor operates the load.
2. The motor responds properly to the controller.
3. There is no binding of the linkage or motor stalling at any point
of travel.
If motor does not operate properly, check for proper voltage or
mechanical binding in linkage or damper.
If questions arise regarding this product, contact your distributor
or representative.
12
14
16
18
20
22
90
10
0
80
70
4
4
46
60
50
40
30
3
6
Y AI
3
R
8
4
0
4
2
20
10
85
(29)
90
(32)
95
(35)
100
(38)
105
(41) (43)
110
35
(2)
35
(2)
40
(4)
40
(4)
(41)
105 110
(43)
45
24
26
ENTHALPY—BTU
28
30
32
PER POUND
34
DR
(7)
45
(7)
50
50
(10)
(10)
55
55
(13)
(13)
60
(16)
60
(16)
65
65
(18)
(18)
70
70
(21)
(21)
75
(24)
75
(24)
80
80
(27)
(27)
85
90
(29) (32)
95
(35)
100
APPROXIMATE DRY BULB TEMPERATURE— F ( C)
(38)
A
A
B
B
C
C
D
D
M11681
RELATIVE HUMIDITY (%
)
1
1
HIGH LIMIT CURVE FOR W7459D.
CONTROL
CURVE
A
CONTROL POINT
APPROX. F (C)
AT 50% RH
73 (23)
B
70 (21)
C
67 (19)
D
63 (17)
Table 1. Motor Operation Checkout
MODEL
DRIVE MOTOR OPEN
DRIVE MOTOR CLOSED
SPRING RETURN
M7415
Power to TR and TR1, jumper
T and T1
Disconnect jumper at T or T1 and disconnect
P or P1, if connected
Disconnect power at TR and TR1
