Danfoss VLT HVAC Drive FC 102
Danfoss VLT HVAC Drive FC 102 code 25: Brake resistor short-circuit
The brake function is disabled and a warning appears because a short circuit has occurred in the brake resistor.
- Code
- 25
- Name
- Brake resistor short-circuit
- Controller
- Danfoss VLT HVAC Drive FC 102
- Type
- Overcurrent
- What it does
- Warning: the equipment keeps running and flags a problem
- Risk
- GREEN In your wheelhouse
- Source
- The manufacturer's manual (subscribers see which manual and page)
Updated November 4, 2026
How to fix it
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- What to do next, in plain words
- What the manual says to do, and the page it is on
- The 1 common cause listed for this code
- The step by step check for this problem, one check at a time
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Questions about this code
What does Danfoss VLT HVAC Drive FC 102 code 25 mean?
The brake function is disabled and a warning appears because a short circuit has occurred in the brake resistor.
Is Danfoss VLT HVAC Drive FC 102 code 25 dangerous?
It is graded green: in a working tech's wheelhouse with standard tools and low risk.
How do I fix Danfoss VLT HVAC Drive FC 102 code 25?
The manual's fix and the step by step check for this code are in WERCS Diagnose, plans from $49 a month. For help right now, WERCS answers 24/7 at (877) 489-3727.
Other Danfoss VLT HVAC Drive FC 102 codes
17 · Control word timeout18 · Start failed23 · Internal fan fault24 · External fan fault26 · Brake resistor power limit27 · Brake chopper fault28 · Brake check failed29 · Heatsink temp30 · Motor phase U missing31 · Motor phase V missing
All 73 Danfoss VLT HVAC Drive FC 102 codes · Every fault code