Bradford-White Corp PDX75S70F(B, CX) Blower Testing, Volt potential exposure. Use caution when

PDX Series

PDX SERVICE PROCEDURE IV

Blower Testing and Replacement

Blower Testing	WARNING
	115 volt potential exposure. Use caution when
Step 1. Position gas control power switch	making voltage checks to avoid personal injury.
to “ON” position and adjust control to call for heat.

Step 2. Remove the three screws (Phillips Screw driver) from control access cover on blower assembly and remove cover (see photo 12).

12

Connect

Disconnect vent

Disconnect

system from top of

manometer to

Does blower energize

Y

pressure switch

blower and remove

pressure tap of

Within 2 minutes?

tubing from blower.

exhaust vent

blower.

(see photo 13)

adapter.

(see photo 13)

15

N

(see photo 15)

14

Remove exhaust

adapter

13

Pressure tap

With blower running, and exhaust

adapter removed from top of

Y

Blower OK

blower, is there a negative

pressure of -2.30" to -2.60" W.C.?

Pressure

N

switch tubing

Determine voltage

N

Is there 115vac across

Y

blue and green wires

Replace blower

problem and correct.

(see photo 18)

Does blower energize after

Y

See pressure

2 minutes, run for 30

switch testing

16

17

seconds and shut down?

Page 17 & 19

N

Disconnect cord set

Is there 115VAC

shown in photo 9. Is

Y

Y

there 115VAC across

across terminals

terminals shown in

shown in photo 17 ?

Reconnect cord set

photo 16

N

shown in photo 9, is

Y

there 115VAC between

N

Replace blower

Incorrect supply

blue wire and green

ground wire

voltage polarity

(see photo 18)

N

Green ground

Determine

Replace

N

Does cord set

wire

18

Is there 115 VAC

N

power source

have electrical

cord set

continuity?

at wall outlet?

problem and

Y

correct.

Y

Blue wire

Check power cord

Y

Repair or replace

Replace

for damage.

power cord

gas control

N

Replace blower	Shown with pressure
	switch removed.
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