Middleby Marshall PS220 Microwave Oven User Manual


 
68
V. BLOWERS
A. PS200-series ovens
All PS200 ovens are equipped with one 1/3hp blower mo-
tor. The motor indirectly drives a pulley on the shaft of the
blower fan with a fan belt.
Two main designs exist for the PS200 indirect fan drive
assembly:
Early design, used through 6/90. This design used
1/2 (12.7mm) bore flange mount bearings and a 1/2
(12.7mm) diameter blower fan shaft. See Figure 25.
Current design, used 7/90 and later. This design uses
5/8 (15.9mm) pillow block bearings and a 5/8 (15.9mm)
diameter blower fan shaft. See Figure 26.
Blower motors on both versions are rated for 208-240V,
single-phase, and are protected by:
A built-in thermal overload protection device.
Two 9A fuses on the inside of the machinery compart-
ment door. Fuse location is shown in Figure 27.
In addition, the blower fan is protected by an air pressure
saftety switch that prevents the burner/heating elements
from activating if the fan is not rotating. See Air Pressure
Safety Switch on Page 81.
Figure 25
Early-style PS200 indirect drive assembly
Figure 26
Current PS200 indirect drive assembly
Direction of rotation
(viewed from
rear of oven)
Direction of rotation
(viewed from
rear of oven)
Figure 27
Blower motor fuses
Early version components
NOTE: If an early-version PS200-series oven has a
failed fan shaft, upgrade the oven to the current drive
assembly using Kit P/N 49810-0121.
Part Number Description
22230-0072 Pulley, 1/2 / 12.7mm bore
22071-0019 Bearing, 1/2 / 12.7mm bore, flange
mount
37900-0094 Fan shaft alignment tool (early)
27381-0066 Motor, 1/3 hp, 200-240V, 50/60Hz ,1 Ph
22181-0034 Fan belt
Current version components
Part Number Description
35900-0232 Shaft, blower fan
22230-0073 Pulley, 5/8 / 15.9mm bore
22072-0025 Bearing, 5/8 / 15.9mm bore, pillow
block mount
27399-0003 Blower fan, 16 / 0.4m diameter
37900-0106 Fan shaft alignment tool (current)
49810-0121 Indirect drive upgrade kit (upgrades
early-style version to current version)
49810-0018 Fan shaft service kit (includes 2 bear-
ings, 1 shaft, and alignment tool )
27381-0066 Motor, 1/3 hp, 200-240V, 50/60Hz ,1 Ph
22181-0034 Fan belt
1. Part number reference
Control
fuse
Blower
motor
fuses
SECTION 3 - SERVICING COMPONENTS