Issue:
Trane Creative Solutions (TCS) may change out the condenser fan blades on modified equipment to account for additional static pressure drop or due to an increased CFM requirement. If a condenser fan or condenser fan motor fails, it is critical that the blade is properly installed to prevent failure and related damage in the field.
Resolution:
Follow the steps below when replacing Multi-Wing condenser fan blades.
1. Confirm the blade doesn’t interfere with the venturi. The center line of the blade should align with the narrowest dimension of the outlet cone.
2. If applied to a different style fan motor (non-Trane OEM) and the motor is being replaced, the motor shaft may have to be trimmed for proper clearance. Be sure to clean off any burr from the cut edge of the shaft so the fan can still fit over the shaft.
3. Some fan motors will be keyed and will have one or more flat spots for the set screw to press down on.
On two set screw fan applications, line the fan up on the motor shaft so that the set screw presses down on the flat spot(s) and the key wherever possible.
If the set screws don't line up with both areas on the shaft and the shaft has a flat spot and a key, align the fan so one of the screws is pressing down on the key.
If one set screw is available with the selected fan, align the fan so the set screw presses down on the key. If the shaft has one or more flat spots, align the fan so the key presses down on one of the flat spots.
4. The key should fit entirely within the key-way of the fan hub. If the key is longer than the hub, then the key should go completely through the hub and stick out the bottom.
5. The setscrew supplied with the Multi-Wing fan will have a nylon patch applied that works as thread locking compound. Apply WD-40 on the screw patch to temporarily relieve the torque absorption. The WD-40 will later evaporate, allowing the threads to become more permanently locked.
6. For better torque and directional control, use a full hex to drive the setscrews.
7. Use the information below for torquing the set screw. Consult Trane Creative Solutions Support if other size setscrew is applied.
1/4" setscrews: 50-60 inch pounds
5/16” setscrews: 85-95 inch pounds
8. Using an orange paint marker, place line across the fan set screw(s).
Notes:
Please contact Trane Creative Solutions for part numbers / ordering assistance of replacement Multi-Wing blades.
An extended as well as stubby 5/32 in. Hex socket bit will be required for torquing the set screws.
WARNING:
Information in this article is intended for use by individuals possessing adequate backgrounds of electrical and mechanical experience and who comply with all federal, state, and local laws, rules, orders, or regulations related to the installation, service, or repair of a heating or central air conditioning product. Any attempt to install, service, or repair a heating or central air conditioning product may result in personal injury and/or property damage. The manufacturer or seller cannot be responsible for the interpretation of the information contained herein, nor can it assume any liability in connection with its use.