10
INSTALLER’S GUIDE
Operate the motor through its complete open-close
stroke. If necessary, release one of the previously tight-
ened 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.
5A. Checkout - For Units with a Honeywell W7459 Control, Only. See 5B for W7212
This motor checkout ensures that:
1. The motor operates the load.
2. The motor responds properly to the controller.
3 . T h e r e i s n o b i n d i n g o f t h e l i n k a g e o r m o t o r
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.
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
Table 1. Motor Operation Checkout - W7459 Control Only
Figure 10. Single Enthalpy Changeover Set Point
Single enthalpy: The enthalpy change-
over 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 terminals + and SR.
12 14 16 18 20 22 24 26 28 30 32 34 36 38 40 42
44 46
90
100
80
70
60
50
40
30
20
10
ENTHALPY—BTU PER POUND DRY AIR
85
(29)
90
(32)
95
(35)
100
(38)
105
(41)
110
(43)
35
(2)
35
(2)
40
(4)
40
(4)
105
(41)
110
(43
45
(7)
45
(7)
50
(10)
50
(10)
55
(13)
55
(13)
60
(16)
60
(16)
65
(18)
65
(18)
70
(21)
70
(21)
75
(24)
75
(24)
80
(27)
80
(27)
85
(29)
90
(32)
95
(35)
100
(38)
APPROXIMATE DRY BULB TEMPERATURE— F ( C)
A
A
B
B
C
C
D
D
M11681
RELATIVE HUMIDITY (%)
1
1
HIGH LIMIT CURVE FOR W7459D.
CONTROL
CURVE
CONTROL POINT
APPROX. F (C)
AT 50% RH
A73 (23)
B70 (21)
C67 (19)
D63 (17)