Bradford White U2TW75T*RN, Руководство по обслуживанию

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U TT W SERVI C E PRO C EDURE
V
Blower Testing and R eplacement
W AR N I N G
11 5 volt potential e x posure. Use caution when
m akin g volta g e checks to avoi d personal injur y .
Blower Testing
Is there 11 5 VAC across
terminals shown in
photo 1 5?
Incorrect supply
volta g e polarity
Determine
power source
problem and
correct.
Does blower ener g ize Within 2
minutes ?
Y
Disconnect cord set
shown in photo 1 2 . Is
there 11 5 VAC across
terminals shown in photo
1 4?
N
See pressure switch
testin g
P a g e 2 0.
Is there 11 5 VAC at
wall outlet ?
Check power cord
for dama g e.
Y
N
Disconnect
pressure switch
tubin g from blower
(see photo 11).
Connect
manometer to
pressure tap of
blower
(see photo 11).
With blower runnin g , and exhaust
adapter removed from top of blower,
is there a ne g ative pressure of - 2 .1 5 "
to - 2 . 3 0" W.C. ?
S t e p 1. Po s i t ion g a s con tr ol pow e r s wi t ch
to “ON” position and adjust control to call for heat .
S t e p 2 . R e mov e t h e t h r ee s c r e w s (Phillip s Sc r e w d r iv e r )
f r om con tr ol a cc e ss cov e r on blow e r a ss e mbly a nd
r e mov e cov e r ( s ee pho t o s 9 a nd 10).
Reconnect cord set shown
in photo 1 2 , is there
11 5 VAC between blue wire
and g reen g round wire
(see photo 16).
Replace blower
Does cord set
have electrical
continuity ?
Disconnect vent
system from top of
blower and remove
vent adapter
(see photo 1 3 ).
Does blower ener g ize after 2
minutes, run for 3 0 seconds
and shut down ?
N
Is there 11 5 vac across blue
and g reen wires
(see photo 16) ?
Blower O K
Y
Repair or replace
power cord
Replace blower
Y
N
N
N
N
Y
Y
Y
Y
N
P ressure switch
tubin g
P ressure tap
Remove exhaust
adapter
Shown with pressure
switch removed.
Green g round
wire
Blue wire
Replace blower
Y
Determine volta g e
problem and correct.
N
P a g e 22
10
11 1 2
1 4 1 5
16
1 3
Replace g as
control
Y
Replace
cord set
N
Control
Access
Cover
Screws
9
R
22