Mitsubishi Preheat Control
July 12, 2024 Jeff Rosenblum
Mitsubishi units have a built-in “preheat” control. It acts like a crankcase heater by sending a small amount of voltage to the compressor windings, causing them to heat up. This control is not always activated from the factory. If you are in a cold climate, this control must be set to “on.” When starting up a Mitsubishi system for the first time, the power should be turned on for a minimum of 12 hours before running the system. This will allow the liquid refrigerant to “boil off” before the compressor runs.
Please see the charts below to determine if a dip switch needs to be turned on or a jumper needs to be adjusted to activate the preheat control. The process is different for different models. More information can be found at www.mylinkdrive.com.
| Jumper | Pre-Heat Control Setting | ||
| MUZ-FS06/09/1215/18NAH MUFZ-KJ09/12/15/18NAHZ SUZ-KA09/12/15/18NAHZ SUZ-KA09/12/15/18/24/30/36NA2 MUZ-FH06/09/12/12/18NA/NAH |
MUZ-GL09/12/15/18/24NA MUZ-GS09/12/15/18/24/30/36NA MUZ-GS09/12/15/18/24NAHZ MUZ-WR09/12/18/24 |
||
| JK | Soldered | Deactivated (initial Setting) | Deactivated (initial Setting) |
| Cut | Activated | Activated | |
| Pre-Heat Control Setting | |||
| Jumper | MUZ-FS06/09/1215/18NAH MUFZ-KJ09/12/15/18NAHZ SUZ-KA09/12/15/18NAHZ SUZ-KA09/12/15/18/24/30/36NA2 MUZ-FH06/09/12/12/18NA/NAH |
||
| MUZ-GL09/12/15/18/24NA MUZ-GS09/12/15/18/24/30/36NA MUZ-GS09/12/15/18/24NAHZ MUZ-WR09/12/18/24 |
|||
| JK | |||
| Soldered | Deactivated (initial Setting) | ||
| Cut | Activated | ||
PRE-HEAT CONTROL
- Pre-heat control is ON at initial setting.
- To turn off the Pre-heat control, consult the service manual.
MXZ-8C, Smart-Multi and SUZ-KA24/30/36NAHZ Pre-Heat is not field selectable.
| Pre-Heating Model No. | |||
| MXZ-3C24NA MXZ-2C20NA2 MXZ-2C20NA3 MXZ-2C20NA4 MXZ-2C20NAHZ MXZ-2C20NAHZ2 MXZ-2C20NAHZ3 MXZ-2C20NAHZ4 |
MXZ-3C30NA MXZ-3C24NA2 MXZ-3C24NA3 MXZ-3C24NA4 MXZ-3C24NAHZ MXZ-3C24NAHZ2 MXZ-3C24NAHZ3 MXZ-3C24NAHZ4 |
MXZ-4C36NA MXZ-3C30NA2 MXZ-3C30NA3 MXZ-3C30NA4 MXZ-3C30NAHZ MXZ-3C30NAHZ2 MXZ-3C30NAHZ3 MXZ-3C30NAHZ4 |
MXZ-5C42NA MXZ-4C36NA2 MXZ-4C36NA3 MXZ-4C36NA4 MXZ-5C42NA2 MXZ-5C42NA3 MXZ-5C42NA4 |
| Pre-Heating Model No. | |||
| MXZ-3C24NA MXZ-2C20NA2 MXZ-2C20NA3 MXZ-2C20NA4 MXZ-2C20NAHZ MXZ-2C20NAHZ2 MXZ-2C20NAHZ3 MXZ-2C20NAHZ4 |
|||
| MXZ-3C30NA MXZ-3C24NA2 MXZ-3C24NA3 MXZ-3C24NA4 MXZ-3C24NAHZ MXZ-3C24NAHZ2 MXZ-3C24NAHZ3 MXZ-3C24NAHZ4 |
|||
| MXZ-4C36NA MXZ-3C30NA2 MXZ-3C30NA3 MXZ-3C30NA4 MXZ-3C30NAHZ MXZ-3C30NAHZ2 MXZ-3C30NAHZ3 MXZ-3C30NAHZ4 |
|||
| MXZ-5C42NA MXZ-4C36NA2 MXZ-4C36NA3 MXZ-4C36NA4 MXZ-5C42NA2 MXZ-5C42NA3 MXZ-5C42NA4 |
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How to activate pre-heat control for the following models: MUZ-D30NA, MUZ-D36NA, MUY-D30NA, MUY-D36NA
- Turn OFF the power supply for the air conditioner before making the setting.
- Set the 2nd Dip Switch of SW1 on the outdoor electronic control P.C. board to ON to activate pre-heat control function.
