Blower Prover Switch - Settings - A.O. Smith SERIES 120 Service Handbook

OPERATION AND SERVICE

BLOWER PROVER SWITCH - SETTINGS

Vent Connection
Blower Prover Switch Exhaust/Outlet
Optional Hot Water Outlet Blower (Draft Inducer)
Figure 15
Table 4
BLOWER PROVER SWITCH TABLE
BTR Model Pressure Setting to Close Switch (Inches W.C.)
500/A -2.85" ± 0.13"
NOTE: The Blower Prover Switch contacts are normally open and will close on a fall in
pressure. This will be a negative pressure (i.e., a vacuum).
Servicing should only be performed by a Qualifi ed Service Agent
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