Fan Selection

Standard Fan Models

F12 12 1140 1360 48.6
F12 12 1750 2250 61.1
F16 16 850 2200 52.1
F16 16 1140 2900 58.9
F16 16 1750 4500 68.2
F20 20 1140 6200 65.3
F24 24 850 3900 53.8
F24 24 1140 5200 61.0
F24 24 1750 7800 74.4
F25 25 1140 7000 62.9
F26 26 850 4030 47.5
F26 26 1140 5610 56.5
F26 26 1750 8500 70.0
F26D 26 850 5250 50.9
F26D 26 1140 7400 61.6
F26X 26 850 5250 50.9
F26X 26 1140 7400 60.1
F26X 26 1750 10,500 73.8

Stainless Steel Fan Models

FS16 16 850 2200 52.1
FS16 16 1140 2900 58.9
FS16 16 1750 4500 68.2
FS24 24 850 3900 53.8
FS24 24 1140 5200 61.0
FS24 24 1750 7800 74.4
FS26 26 850 4030 47.5
FS26 26 1140 5610 56.5
FS26 26 1750 8500 70.0
FS26X 26 850 5250 50.9
FS26X 26 1140 7400 60.1

Hazardous Duty Fan Models

F12H 12 1750 2250 61.1
F16H 16 1750 4300 68.2
F24H 24 1140 5200 61.0
F24H 24 1750 7800 74.4
F26H 26 1140 5610 56.5
F26H 26 1750 8500 70.0

Airflow and Sound data test parameters.

(1) Actual Airflow in CFM as measured with Horizontal Airflow on discharge side of one 15” deep transformer radiator.

(2) Nominal Sound Pressure values expressed are determined from Sound Power measurements performed in accordance with AMCA 300-08 and are based on a 2 meter measurement distance.

*Blade diameter measurements are approximate.


Airflow Requirement

  • Determine the total airflow requirement of the Transformer. The Transformer manufacturer should have the airflow requirement necessary for cooling the Transformer.
  • If unsure of the airflow requirement needed, feel free to contact Krenz & Company for assistance, we have decades of experience predicting cooling requirements for Transformers.
  • Each fan manufacture publishes its own airflow standard; ensure that the airflow requirement listed matches the Krenz & Company standard. If a different standard is listed please contact Krenz & Company for assistance in comparing different airflow standards. Krenz & Company owns a full testing facility and an understanding of the airflow standards utilized throughout the industry to help assist our customers.

Fan Size

  • Choose the appropriate sized fan model based on the radiator packaging considerations and total air-flow requirement determined from above.
  • Pay careful attention to the desired fan mounting style (Vertical or Horizontal Airflow) and total airflow requirement to ensure that enough fans can be properly packaged on the radiator.
  • In some instances it may be required to install fans for both Vertical and Horizontal Airflow.

Available Power Supply

  • Choose the appropriate fan part number based on the phase and voltage of the available fan operating power supply.
  • Ensure that enough amperage is available to properly energize and operate all the fans required for the total airflow requirement. Specific fan electrical performance is listed on each fan page.


  • Plug and Receptacle connections allow for a convenient disconnect of the fans and are available in several different standard lengths. Custom lengths are available, upon request, for our Male Plug and Cords, Female Plug and Cords, and Female Receptacles.
  • Each Plug and Cord set requires the opposite gender Receptacle. For instance a Male Plug and Cord would mate with the Female Receptacle, while the Male Receptacle would mate with the Female Plug and Cord. Each connection style is sold separately to allow for custom variations in length. The Male component is installed on the fan while the Female component is installed on the power side.
  • Choose the appropriate length cord based on the fan installed location and location of either the nearest junction box or control box.
  • For installations where a common disconnect point is not desirable we have available our SO Cord with flying leads. These are custom cut per order and are available in any length desired.
  • Optional styles of connections are available upon request; please contact Krenz & Company with your requirements or needs.

Environmental Considerations

  • Standard fan assemblies are built with our industry standard Hot Dipped Galvanized fan guards that are galvanized per ASTM A123.
  • For increased guard corrosion protection (ex. heavy marine environments) our standard FS line of fans are equipped with 304 Stainless Steel guards.
  • Please contact factory for optional upgrades for increased fan corrosion protection.
  • See our Hazardous Duty Fan line for use of fans in Hazardous locations requiring Explosion Proof motors.

Mounting Hardware

  • For Horizontal Airflow Mounting Orientations we have several different options to choose from.
    • Flush Mount Kits.
    • Zinc Plated Tee-Bolt Kits.
    • Stainless Steel Tee-Bolt Kits.
  • For Vertical Airflow Mounting Orientations we have our header mount kits available for all of our popular fan sizes.
  • For Optional Mounting Orientations we have mounting styles available for specific applications.
    • Fan Base Mount Adapter is utilized in applications when the fan is to be base mounted to a structure or one of our following optional mounts.
    • Tripod Mounts are available for either temporary cooling installations or installations that do not allow for mounting of the fan to the radiator. The Fan Base Mount Adapter is required for Tripod mounting.
    • Stand-off Mounts are available for angled mounting of the fan on the radiator to help direct the airflow of the fan away from an obstruction. The Fan Base Mount Adapter is required for Stand-off mounting.

Control Enclosure

  • Selection of the cooling fan control is determined based on the fan part number, desired number of fans to be energized at the same time, and how many operational stages (single or two stage).
  • Single stage controls energize all the fans at the same time based on one temperature switch setting of the Top Oil Thermometer. Once the Transformer Oil temperature reaches the temperature switch setting, the Top Oil Thermometer sends a signal to the control to energize all the fans.
  • Two stage controls work very similar except that they utilize two different temperature switch settings of the Top Oil Thermometer and thus only energize half of the fans at a time. After the first stage of fans have been energized if the Transformer Oil temperature continues to rise to the second temperature switch setting, the Top Oil Thermometer sends a signal to the control to energize the second stage of fans.
  • Each Krenz & Company control enclosure is sized based on the starting curves of Krenz & Company fans and thus includes the properly sized main and branch breakers. See the selection table to help determine the proper fan control size. Please feel free to contact Krenz & Company for help in Control Enclosure selection or customization.

We understand that the selection criteria coupled with the vast number of components Krenz & Company has to offer is extensive. Therefore please feel free to contact us at any time for assistance in selecting a fan, connection, mounting hardware, or complete cooling package and we would be happy to assist you.