WFCO WF-9855
WFCO WF-9855 55 Amp Deck Mount Converter User Manual
Model: WF-9855 | Brand: WFCO
Introduction
This manual provides comprehensive instructions for the installation, operation, and maintenance of the WFCO WF-9855 55 Amp Deck Mount Converter. This versatile power source solution is designed for convenient deck-mount installation and features a 3-stage battery charging system with LED fuse boards. Please read this manual thoroughly before installation and operation to ensure safe and efficient use.
Safety Information
Always observe the following safety precautions to prevent injury or damage to the converter or connected equipment:
- Ensure the power source is disconnected before installation or maintenance.
- Installation should be performed by a qualified technician if you are unsure of the process.
- Do not expose the converter to water or excessive moisture.
- Ensure proper ventilation around the unit to prevent overheating.
- Use appropriate wire gauges for all connections as specified in the installation section.
- Verify correct polarity for all DC connections.
What's in the Box
- WFCO WF-9855 55 Amp Deck Mount Converter
Please inspect all components for any signs of damage upon unpacking. If any items are missing or damaged, contact WFCO customer support immediately.
Features
- Quiet operation: The cooling fan activates only when required by the electrical load, ensuring minimal noise.
- Easy Installation: Features fully insulated DC connections and an open-top design for fast and nearly effortless setup.
- Model WF-9855: Designed for optimal performance.
- Output: Provides 55 Amps DC.
- Input: Operates on 105-130 VAC, 60 Hz, with a power consumption of 940W.
- Bulk Mode (Quick Charging Voltage): 14.4V DC for rapid battery charging.
Specifications
| Attribute | Value |
|---|---|
| Manufacturer | WFCO |
| Brand | WFCO |
| Model | WF9855 |
| Item Weight | 4.3 pounds |
| Product Dimensions | 8.6 x 5.9 x 3.9 inches |
| Item Model Number | WF-9855 |
| Manufacturer Part Number | WF-9855 |
| Wattage | 940 watts |
| ASIN | B004A30UHG |
| Date First Available | October 30, 2010 |
Installation
The WFCO WF-9855 converter is designed for deck-mount installation. Follow these steps for proper setup:
- Choose a Location: Select a dry, well-ventilated area for mounting the converter. Ensure there is sufficient space around the unit for airflow and access to connections.
- Mount the Converter: Secure the converter to a stable surface using appropriate fasteners through the mounting tabs.
- AC Input Connection: Connect the 105-130 VAC, 60 Hz input power to the designated AC input terminals on the converter. Ensure the power source is disconnected before making this connection.
- DC Output Connections: Connect the DC output wires to your RV's 12V distribution panel. The WF-9855 features fully insulated DC connections and an open-top design for ease of wiring. Ensure correct polarity: positive (+) to positive and negative (-) to negative.
- Grounding: Connect the ground wire from the converter to a suitable chassis ground point.
- Battery Connection: Connect the converter to your RV's battery bank. The 3-stage charging system will automatically manage battery charging.
- Verify Connections: Double-check all wiring connections for tightness and correct polarity before restoring AC power.

Image: WFCO WF-9855 55 Amp Deck Mount Converter. This image shows the overall view of the converter unit, highlighting its compact design and connection points.
Operation
Once properly installed, the WFCO WF-9855 converter operates automatically:
- Power On: After connecting to an AC power source, the converter will automatically begin supplying 12V DC power to your RV's systems and charging the battery.
- 3-Stage Battery Charging: The converter features a smart 3-stage charging system:
- Bulk Mode (14.4V DC): Rapidly charges deeply discharged batteries.
- Absorption Mode (13.6V DC): Maintains a steady voltage to fully charge the battery.
- Float Mode (13.2V DC): Reduces voltage to a trickle charge to maintain battery health and prevent overcharging.
- Quiet Fan Operation: The cooling fan will only activate when the internal temperature rises due to electrical load, ensuring quiet operation during low-demand periods.
- LED Fuse Boards: The integrated LED fuse boards provide visual indication of blown fuses, simplifying troubleshooting.
Maintenance
The WFCO WF-9855 converter requires minimal maintenance. Follow these guidelines to ensure optimal performance and longevity:
- Keep Clean: Periodically clean the exterior of the converter with a dry, soft cloth. Ensure ventilation openings are free from dust and debris.
- Check Connections: Annually inspect all electrical connections for tightness and corrosion. Tighten any loose connections.
- Ventilation: Ensure the area around the converter remains clear to allow for proper airflow and cooling.
- Fuse Inspection: If a 12V appliance or light stops working, check the corresponding fuse on the LED fuse board. A lit LED indicates a blown fuse. Replace blown fuses with the correct amperage rating.
Troubleshooting
Refer to the table below for common issues and their solutions:
| Problem | Possible Cause | Solution |
|---|---|---|
| No 12V DC power output | No AC input power; Blown fuses; Loose connections; Converter fault | Check AC breaker/shore power; Inspect and replace blown fuses; Tighten all connections; If problem persists, contact support. |
| Battery not charging | Blown fuses; Loose battery connections; Battery fault; Converter not receiving AC power | Check fuses; Verify battery connections; Test battery condition; Ensure AC power is supplied to converter. |
| Converter fan runs constantly or loudly | High electrical load; Restricted airflow; Fan malfunction | Reduce 12V load if possible; Clear any obstructions around the converter; If fan noise is excessive without load, contact support. |
| LED on fuse board is lit | Blown fuse on that circuit | Replace the blown fuse with a new fuse of the same amperage rating. |
For issues not covered here, or if troubleshooting steps do not resolve the problem, please refer to the official user manual PDF or contact WFCO customer support.
Additional Resources
For more detailed information, you can refer to the official PDF documents:
Warranty and Support
WFCO products are backed by a manufacturer's warranty. For specific warranty terms and conditions, please refer to the documentation included with your product or visit the official WFCO website. For technical support, parts, or service, please contact WFCO customer service directly. Contact information can typically be found on the product packaging or the official WFCO website.
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