WF-9855 55 Amp RV Power Converter for Lithium Battery - Quiet 3-Stage

In this review of the WF-9855 55 Amp RV power converter, the bottom line is simple: this unit is for RV owners who run a lithium battery bank and need a reliable, direct replacement for WF-9800 series converters. The reviewer found the standout reason to buy is its tailored design for lithium battery charging that delivers a 14.6VDC three-stage charge and matches expected lithium charge profiles, making it a straightforward swap-in for WF-9855, WF-9855-AD and related models.

Key Features

• 55 Amp output: Delivers up to 55 A of charging current, suitable for medium-sized RV lithium battery banks and consistent charging under load.
• Three-stage charging: The converter uses a three-stage charge algorithm to bring lithium batteries to full capacity efficiently while avoiding overcharge.
• Silent fan: An upgraded pure copper silent fan reduces audible noise by about 30% while providing improved cooling for sustained operation.
• Protective functions: Built-in overcharge, overvoltage, overcurrent, high temperature and short circuit protections increase safety and protect the battery and RV wiring.
• 5-year warranty: Backed by a five-year manufacturer warranty and responsive support, which provides extra confidence for long-term installations.
• Direct compatibility: Designed as a replacement for WF-9855, WF-9855-AD, WF-9855-LIS and other WF-9800 series units, simplifying upgrades and repairs.

Who It's For

The WF-9855 is best for RV owners and technicians who need a reliable, plug-and-play replacement for WF-9800 series power converters or want a converter that is specifically tuned for lithium battery charging. It fits owners running moderate lithium capacity systems where a 55 A charger provides a good balance between charging speed and heat management.

Those who should look elsewhere include owners with very large battery banks who need higher than 55 A charging, or users who prioritize the absolute quietest electronics available, since some customers still report fan noise even with the reduced-noise design.

Pros & Cons

Pros

• Provides a correct 14.6V three-stage charge that matches lithium battery requirements and completes charging reliably.
• Multiple built-in protections reduce the risk of damage to battery or electrical system during faults.
• Quality construction and a 5-year warranty give confidence in long-term use and value for money.

Cons

• Although the fan is quieter than older units, some users still note audible noise under certain conditions.
• Limited to 55 A output, so it may be undersized for very large lithium banks that need faster recharge rates.

Specifications

Power	950 Watts
Output Current	55 Amps
Output Voltage	14.6 VDC
Input Voltage / Frequency	105-130 VAC, 60 Hz
Charging Method	Three-Stage Charging
Protections	Overcharge, Overvoltage, Overcurrent, High temp, Short circuit
Warranty	5-year manufacturer warranty

Our Verdict

The WF-9855 is a practical, value-oriented converter for RV owners who need a compatible, purpose-built lithium battery charger to replace WF-9800 series units. Its three-stage charging, safety protections and long warranty make it a sensible buy for typical RV systems, though buyers with very large battery banks should seek higher current options.

Frequently Asked Questions

Is this a direct replacement for older WF-9800 series converters?
Yes, it is designed to be compatible with WF-9855, WF-9855-AD, WF-9855-LIS and other WF-9800 series converters for straightforward replacement.

What voltage does it charge to?
The converter charges to 14.6 VDC using a three-stage charging profile suitable for lithium batteries.

How noisy is the unit in operation?
The unit uses a pure copper silent fan that reduces noise by about 30% compared with older designs, but some users may still hear fan noise under higher load or in quiet surroundings.