Danfoss VLT HVAC Drive FC 102
Danfoss VLT HVAC Drive FC 102 code 45: Ground fault 2
The drive stops operating because it has detected a secondary ground fault in the system.
Safety first. This code involves a gas, flame or electrical hazard. Do not keep resetting it. Leave burner, gas train and high voltage work to a qualified technician. WERCS answers 24/7 at (877) 489-3727.
- Code
- 45
- Name
- Ground fault 2
- Controller
- Danfoss VLT HVAC Drive FC 102
- Type
- Ground fault
- What it does
- Fault: the equipment trips and stops
- Risk
- RED Specialist territory
- Source
- The manufacturer's manual (subscribers see which manual and page)
Updated November 4, 2026
How to fix it
Subscribers get:
- What to do next, in plain words
- What the manual says to do, and the page it is on
- The step by step check for this problem, one check at a time
- Booking a live video call with Ben, a master booth technician ($250/hr, paid per call)
Questions about this code
What does Danfoss VLT HVAC Drive FC 102 code 45 mean?
The drive stops operating because it has detected a secondary ground fault in the system.
Is Danfoss VLT HVAC Drive FC 102 code 45 dangerous?
It is graded red, specialist territory: it involves a burner, gas, flame or safety lockout, so leave the repair to a qualified technician.
How do I fix Danfoss VLT HVAC Drive FC 102 code 45?
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
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