1. ST9120U1003 Universal Electronic Fan Timer Training Module
A new addition to the Honeywell line of Universal controls
Designed specifically for the service technician In
Service situations

2. ST9120U - What You Will Learn:
Product Overview
Set Up
Installation
Troubleshooting
Product Cross Reference
ST9120 Advantage

3. What is the ST9120U Electronic Fan Timer?
A universal electronic fan timer that integrates control of all combustion blower and circulating fan operations in a gas warm air appliance
Monitors the thermostat for heat, cool and fan demands.
Runs the induced draft blower motor and runs the circulating fan (up to two speeds) as needed.
Monitors limit switch strings and energizes ignition control.
Central wiring point for the electrical components of the furnace. Saves time!
One part number:
ST9120U1003

4. ST9120U Electronic Fan Timer Features
Why choose the Honeywell ST9120U?
Universal application
Replaces over 25 existing Honeywell controls
Easy installation
DIP switch selectable circulating fan delays
Heat on/off delay
Cool on/off delay (cool off fixed at 30 seconds)
Single model services multiple furnace applications
Included with the ST9120U:
Wiring information and adapter for the ST9101
Original appliance application
Delay timing recommendation
Quality construction for a long service life

5. Installation
(If you are talking to technicians hand out copies of the installation instruction sheet as you go through the Installation, setup and troubleshooting sections of this presentation)

6. Installation of the ST9120U
Location and Mounting
Mount the ST9120U Electronic Fan Timer in the appliance wiring compartment or furnace vestibule
Mounting screws provided
Wiring
Make sure that all wiring complies with local codes and ordinances.
Disconnect power before making wiring connections.

7. Set-Up

8. Set up of the ST9120U Setting DIP switches Heat fan-on delay
On: 30/60 Seconds
Starts timing when main valve energized
Heat fan-off delay
Off: 60/100/140/180 Seconds
Starts timing when main valve is de-energized
Cool fan-on delay
On: 4/30 Seconds
Starts with call for cooling
Cool fan-off delay fixed at 30 seconds
Post Purge: 5 seconds

9. Set up of the ST9120U
Recommended dip switch settings are included in the installation instructions as well as the Honeywell Residential Combustion Application and Selection Guide.

10. Troubleshooting

11. Troubleshooting of the ST9120U
Look for appropriate voltages at the ST9120U terminals
Check operation and timing of:
Combustion blower
Fan at heating speed
Fan at cooling speed
Check limit operation and system response
Note: The ST9120U schematics show internal switching to clarify operation and assist in troubleshooting.

12. Product Cross Reference

13. Product Cross Reference
The ST9120U replaces over 25 existing Honeywell controls:
ST9101A1006
ST9120C1020
ST9120C4016
ST9120G2016
ST9101A1014
ST9120C2002
ST9120C4040
ST9120G2024
ST9101A1022
ST9120C2010
ST9120C4057
ST9120G2032
ST9120A1006
ST9120C2028
ST9120C5005
ST9120G4004
ST9120A2004
ST9120C3000
ST9120C5013
ST9120G4012
ST9120B1005
ST9120C3018
ST9120D3009
ST9120G4038
ST9120C1012
ST9120C4008
ST9120G2008

14. Product Cross Reference
Where do I find Honeywell universal fan timer cross reference information?
Honeywell Application Selection and Cross
Reference Guide – Form
Honeywell Laminated Truck Visor – Form
Honeywell Residential Technical Support:

15.
See Cross Reference Search box in right column.

16. ST9120U Advantage
When promoting the ST9120U keep these advantages in mind:
The ST9120U universal control replaces over 25 existing Honeywell controls. This in turn, reduces inventory and saves time looking for the right part.
A central wiring point for most of the electrical components of the furnace makes installation easy and gets the installer on to the next job faster.
Easy to set selectable heat and cool on/off settings adapt to the application.
The ST9120U makes the choice simple; one control saves time and money, improving your bottom line.

17. ST9120U1003 Universal Electronic Fan Timer Knowledge Test

18. ST9120U Knowledge Test
Now that you completed this training module, take the short quiz to test your knowledge.

19. Test
The ST9120U Universal Electronic Fan Timer controls the blower and circulating fan in gas warm air appliances? T or F
The ST9120U is a central wiring point for most of the electrical components in the furnace? T or F
The ST9120U replaces over 25 Honeywell and competitor controls? T or F
The universal electronic fan timer monitors the thermostat for heat, cool and fan demands? T or F
The heat and cool on/off delays are set through dip switches? T or F
Honeywell only has one resource for cross reference information? T or F

20. Answer Key T F