High-Efficiency Commercial Gas Series - Service Manual
Technical Literature Department
27
Ashland City, Tennessee © 2008
Servicing should only be performed by a Qualified Service Agent
BLOWER SPEED CONTROL 199 AND 250 KBtu/hr MODELS
The input of the 199 and 250 KBtu/hr
models is determined by blower speed. The
input of the water heater may be determined
by clocking the meter as shown on page 5 or
by making sure the blower is 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: Removing the plug shown 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 terminal on blower speed control
connection.
Meter red probe
connected to
open terminal on
plug
