Bradford White EF120T4003N3, Руководство по обслуживанию

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Service Procedure VI:
Blocked Vent Pressure Switch Testing and Replacement
Check Exhaust Tube Pressure
Is exhaust venting
system blocked or
obstructed? Also
check condensate
elbow and drain.
Replace blocked exhaust vent switch
(see Blocked Exhaust Vent Switch
Testing and Replacement, pg 32).
Is pressure in exhaust tube near 2.7” W.C. or more? If so, correct
blockage (below). If exhaust pressure is low (0.40” or less), replace
pressure switch. Is pressure in intake tube near 2.3” W.C. or more? If
so, correct blockage (below). Replace blocked exhaust vent switch
(see Blocked Exhaust Vent Switch Testing and Replacement, pg 32).
With ohmmeter check
pressure switch for
continuity. Contacts
should be closed.
Pressure switch is O.K.
With manometer, take a
reading at the exhaust tube
pressure tap location. Is
value .4” or less? (see
image below).
N
Y
Clear obstruction.
Determine cause
and correct.
Is vent system total
length compliant with
vent tables in the
instruction manual?
Reconfigure vent
system to be
compliant with vent
tables (see
Specifications, pg 5).
Y Y
N
N
N
Y Y
Y
Exhaust tube pressure tap located behind
serivce panel access doors at bottom of heater
Exhaust tube pressure
tap location
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