3
Bracket -
Left
Relay Box
Bracket -Right
Relay Box
Bracket
- Right
Bracket
- Left
Figure 3. Relay Box Installation
MGHA & MMHA Only
p/n 903092A, 2-wire relay
p/n 902898A, A/C Heat Pump
(4-7 wire) relay box
Relay Box
Bracket
Table 2. Three and Four Speed Blower Speed Selec-
tion for MG & MM - 05 Models
Table 2A. Blower Speed Selection M1 Models
Blower Speed Selection Chart
For use with Blower Kit No. 902809
Furnace Input
Heating
Speed
Setting
Cooling Speed/ Evap Coil
024, 030
036
042, 046 &
048
086
M*
M*
H
H
070, 075, 077
L**
M*
H
H
056, 066, 070
L**
M*
H
H
*MH on Relay Box circuit board.
**ML on Relay Box circuit board.
Blower Speed Selection Chart
For use with Blower Kit No. 902809
Furnace Input
Heating
Speed
Setting
Cooling Speed/ Evap Coil
024, 030
036
042, 046 &
048
086
M*
M*
H
H
070, 075, 077
L**
M*
H
H
056, 066, 070
L**
M*
H
H
Blower Speed Selection Chart
For use with Blower Kit No. 903412 1/3 HP 2 Speed
Furnace Input
Heating
Speed
Setting
Cooling Speed/ Evap Coil
024
036 & 030
077, 086, 090
H
ML*
H
056, 066, 070
ML*
ML*
H
*ML on Relay Box circuit board is low speed.
Blower Speed Selection Chart
For use with Blower Kit No. 903413 1/2 HP 4 Speed
Furnace
Input
Heating
Speed
Setting
Cooling Speed/ Evap Coil
024
030 &
036
042
048
077, 086, 090
ML
ML
ML
MH
H
056, 066, 070
L
ML
ML
MH
H
Blower Speed Selection Chart
For use with Blower Kit No. 903414 3/4 HP 4 Speed
Furnace
Input
Heating
Speed
Setting
Cooling Speed/ Evap Coil
024
030 &
036
042
048
077, 086, 090
ML
ML
ML
MH
H
056, 066, 070
L
ML
ML
MH
H
Blower Speed Selection Chart
For use with 3 Ton 3 Speed Blowers
Furnace Input
Heating
Speed
Setting
Cooling Speed/ Evap Coil
024
030
036
056
L**
L**
M*
H
066, 070, 077
M*
L**
M*
H
086, 090
H
L**
M*
H
**L is ML on circuit board.
*M is MH on circuit board.
