Check Exhaust Tube Pressure - Bradford White EF100T150(E)*(N Service Manual

Check Exhaust Tube Pressure

With monometer, take a
reading at the exhaust
tube pressure tap location.
Is value negative (-) or
slightly postitive
(see illustration below).
With ohmmeter check
pressure switch for
continuity. Contacts should
Pressure switch O.K.
58
Blocked Vent Pressure Switch Testing and
Replacement for serial number "CF" and later
Is exhaust venting
system blocked or
N
obstructed? Also
check condensate
elbow and drain.
Y
Is vent system total
length compliant with
vent tables in the
instruction manual?
blocked vent switch.
(see "Blocked Vent
Switch Testing and
Replacement")
N
be closed.
Y
Clear obstruction.
Y
Determine cause
and correct.
N
Reconfigure vent
system to be
N
compliant with
vent tables (see
"Specifications").
Y
Replace
Is pressure in exhaust tube near 2.7" w.c. or more? If so, correct
blockage (above). If exhaust pressure is low (0.40" or less),
replace pressure switch.
Exhaust Tube
pressure tap location
Exhaust tube
at bottom of heater
58