Overview
This procedure provides the required service menu access password and outlines two critical operational settings — Carter Oil Timer and Blackout Setting — which are used to bypass or shorten compressor start-up delays during service or commissioning.
The Danfoss controller is fitted to Fujitsu Airstage RTPU (Rooftop Package Units) to manage compressor protection sequences, oil management, and restart logic after power interruptions.
1. Accessing the Service Menu
Service Menu Password
To access advanced configuration parameters on the Danfoss controller:
Password:
5653Navigate via:
Enter the above password when prompted to unlock technician-level adjustments.
2. Compressor Delay Functions
A. Carter Oil Timer Setting
This function protects the compressor by allowing oil migration and equalization before start-up following power application or long shutdowns.
Usage (Service Mode):
If power has just been energised, and immediate compressor operation is required:
Enter the Service Menu (Password 5653).
Locate the Carter Oil Timer parameter.
Bypass or reduce the time delay as needed (e.g., from standard 300 seconds to 0–30 seconds).
Purpose: Enables prompt compressor engagement during testing or post-maintenance restart, without waiting for the full oil delay cycle.
B. Blackout Setting
The Blackout Setting determines compressor restart delay following a power outage or supply interruption.
Usage (Service Mode):
If sump heaters have been ON and oil temperature is adequate:
Enter Service Menu → Blackout Setting.
Reduce or bypass the restart delay time to allow the compressor to start sooner.
Purpose: Minimizes downtime when power restoration occurs, avoiding unnecessary delay once oil conditions are already stable.
3. Operational Notes
Always ensure oil sump temperature exceeds 15°C before bypassing any protective delay to prevent compressor damage.
Do not permanently disable timing protections; these are intended only for commissioning, diagnostics, or supervised service.
After testing, restore factory delay parameters to ensure long-term compressor protection.
Record any temporary bypass actions in service documentation for traceability.
4. Reference Quick Guide
| Function | Menu Access Path | Default Purpose | Service Adjustment |
|---|---|---|---|
| Service Menu Access | Main → Settings → Password | Unlocks advanced control | Password: 5653 |
| Carter Oil Timer | Service → Compressor Control | Oil equalization delay | Reduce or bypass for testing |
| Blackout Setting | Service → Power Recovery | Restart delay after outage | Reduce if sump heaters active |