Dual Inlet Backward Curve Fan Installation

The models listed at the end of this newsletter are designed to meet federal Fan Energy Rating (FER) requirements and are scheduled to be released into production. These furnaces use a dual-inlet backward curve fan wheel. The installation of these wheels into the blower housing and onto the motor shaft during service or replacement varies slightly from current standard field installation practices. 

Technical Information:

Typical installation of traditional blower wheels requires you to slide the wheel on and center it into the housing. For the new wheel and motor design, the installer, after completing installation of the motor to the housing, will slide the blower wheel to the stop mechanism designed into the flat of the motor shaft per Carrier’s Specifications.

Carrier’s Installation instructions for the blower wheel are as follows as per TIC 2019-0012.

Installation of the DIBC wheel:

1. Lay blower housing on non-motor side
2. Insert DIBC wheel into blower housing
3. Place blower housing orifice onto blower housing, aligning motor mounting holes
4. Install motor shaft into hub of DIBC blower wheel
5. Align motor mounting arms and install 4 motor mounting screws. Tighten motor mounting screws to 40 in-lb.
6. Upright blower housing assembly
7. Align set-screw with flat on motor shaft
8. Push blower wheel toward motor until wheel hub bottoms out on the motor shaft and tighten set-screw to 160 in-lb.
9. Spin blower wheel and check for interference. Adjust as needed.
10. Install blower cutoff in housing
11. Install green ground wire from motor harness to sheet metal of housing
12. Reinstall blower housing mounting brackets to blower housing and install into furnace

Models Affected

Carrier

59SC5B040E141110
59SC5B060E141112
59TP6B040V141110

59TP6B060V141112

Bryant           

915SB30040E14A-A
915SB36060E14A-A
926TB30040E14A-A
926TB36060E14A-A 

Payne 

PG95ESAA30040AAA
PG95ESAA36060AAA
PG96VTAA30040AAA

PG96VTAA36060AAA