P/N 42002-0024S
Stack Flue
Sensor (SFS)
3700 0600
Risk of fire, explosion, and electrical shock.
Heater service and repair must be performed by a qualified
installer, service agency, or the gas supplier.
Location
The Indoor Stack Flue Switch (ES2) / Stack Flue Sensor
(SFS) is located on the Exhaust Elbow.
Function
The Stack Flue Sensor prevents the flue gas output from
exceeding 500°F ±18°F (260°C ±8°C).
Servicing Procedure
To replace the Indoor Stack Flue Switch or Stack Flue
Sensor (See Figure 2, Page 2):
1. Turn off the filter pump and all electrical power to the
heater.
2. Allow the heater to cool for at least half an hour before
proceeding.
3. Unbolt and remove the Upper Left and Upper Right
Jackets from the heater.
4. Disconnect the wires from the old Indoor Stack Flue
Switch or Sensor.
5. Remove the old Switch or Sensor by turning it counter-
clockwise with a 1/2” open end wrench.
6. Reverse Steps 1 through 5 above.
Risk of carbon monoxide poisoning. BE SURE
to seal the Stack Flue Sensor with a bead of RTV sealant
before threading it into the exhaust elbow.
Stack Flue Sensor
Sta-Rite Pool/Spa Group
293 Wright Street, Delavan, WI 53115
International:
262-728-5551, FAX: 262-728-7550
www.starite.com
Union City, TN • Delavan, WI • Mississauga, Ont. • Murrieta, CA
© 2004, Sta-Rite Industries
Printed in U.S.A.
S381
(Rev. 11/16/04)
FIGURE 1
