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ULTRAFORCE COMMERCIAL GAS WATER HEATER
SUF 120 thru 400 SERVICE HANDBOOK
State Water Heaters – Technical Training Department 32
Ashland City, Tennessee © 2009
Servicing should only be performed by a Qualified Service Agent 198152-002
BLOWER SPEED CONTROL SUF 199 AND 250
The i nput of the SUF 199 and SUF 250 is
determined by the blower. The input of the
water heater may be determined by clocking
the meter as shown on page 5 or by making
sure the blower i s receiving the proper Hz
signal. The blower rpm is controlled by the
Central Control Board (CCB). The signal to
the blower may be measured by attaching a
MULTIMETER that has a Hertz (Hz) setting
as shown in the illustration to the right. If the
Hz signal is /
Model
Hz
Hz
199 N
133
87
250 N
133
87
199 LP 200
156
250 LP 266
96
Note: R emoving the plug show n in the
illustration will cause the blower to accelerate
and the input of the water heater to increase
to a much higher rate.
Meter black lead is connected to ground (not
shown) and the red lead is connected to an
open te rminal o n bl ower spee d con trol
connection.
Meter red probe
connected to
open terminal on
plug