This project utilizes a Furman CN-15MP (15-Amp) or Furman CN-20MP (20-Amp) to power off an appliance when water is detected by the Floodstop system. This project can be very useful to power off a washing machine, water recirculator, or tankless hot water heater if a leak is detected. In particular, appliances that can pump water such as a washing machine have an extra vulnerability for flooding and could potentially continue pumping water even if the water supply has been shut off by the Floodstop valve. For these type of devices, you may want to automatically power them off to ensure any motors or pumps are not contributing to the flooding condition.

Project Objective

The following diagram illustrates this project's goals.

Shopping List

• Floodstop Protection System (See a complete listing of available Floodstop products)
• Furman Power Controller (See a listing of other Furman Power Controllers)
• A length of 2-conductor low-voltage wire (bell wire, alarm wire, speaker wire, etc.) (* length is based on your installation requirements)

All Floodstop Models Other Furman Power Controllers Projects

Furman CN-15MP / CN-20MP Power Controller

The Furman power controller product line is a heavy-duty inustrial power controller that can easily be controlled externally with either a dry contact closure or a low-voltage DC signal depending the the model. This makes the Furman power controller prefectly suited to work with the Floodstop contoller to add the capability of powering off an appliance when a leak is detected.

The Furman CN-15MP (15-amp) / CN-20MP (20-amp) is the latest generation and the sucessor of the original Furman MP-15/MP-20 power controller Furman power controller. The CN-15MP is adequate for most installations as most modern appliances draw (require) less than 15 amps and most homes are only wired for a 15-amp circuits. The CN-20MP is designed for 20-amp circuits and typically requires a special 20-amp outlet. If you have a CN-20MP but only have 15-amp outlets, you can cut off and replace the plug on the CN-20MP with a standard 15-amp plug but you must take care to never overload the circuit with an appliance that draws more than 15-amps.

The Furman CN-15MP / CN-20MP is powered on by default and can be powered off simply by closing the circuit between the two FORCE OFF terminal pins. (Please see the DIP switch settings section of this article to make sure the Furman is configured properly for this operation.)

Floodstop + Furman CN-15MP / CN-20MP

The CN-15MP / CN-20MP is extremely simple to integrate with the Floodstop's N.O. (normally-open) dry contacts. The Furman CN-15MP / CN-20MP is powered on while the Floodstop's output circuit is OPEN and will be powered off when the Floodstop's output is closed providing a closed circuit between the two FORCE OFF terminal pins on the Furman. The logic diagram below depicts how we will use the Floodstop's dry contact output connection to control the Furman MP-15/20 power controller.

Connect Floodstop to the Furman CN-15MP / CN-20MP

First located the N.O. (normally-open) output on the bottom of the Floodstop controller. This is the port we will be using to interface to the Floodstop.

To control the Furman CN-15MP / CN-20MP with the Floodstop you need only to connect each of the Floodstop's N.O. output conductors to the two FORCE OFF terminal pins on the Furman power controller. In this project, it does not matter which conductor on the Floodstop is connected to which of the 12VDC or REM terminals. Polarity does not matter in this circuit.

A short connection wire should have been included in the Floodstop package that includes the necessary plug to connect to the Floodstop's output port. Most likely this connection "pigtail" will be too short for your final installation, so you can extend this connection wire by splicing on the end of a 2-conductor low-voltage wire that meets your project's length requirements.

That's it, you are ready to test and install this project! The Furman CN-15MP / CN-20MP should now power off the high-voltage circuit the appliance is plugged into anytime the Floodstop senses a water leak! Please note that once the sensor is tripped, it does not automatically restore power when the Floodstop stops sensing moisture. To restore power to the appliance, the Floodstop sensor must be completely dry and you must press the OPEN button on the Floodstop controller. This will both open the water valves and signal the Furman CN-15MP / CN-20MP to restore power to the appliance.

Floodstop + Furman CN-15MP / CN-20MP DIP Switch Settings

In order for the Floodstop's N.O. output logic to work properly with the Furman CN-15MP / CN-20MP's FORCE OFF pins, the force off feature must be configured as N.O. (normally-open) via DIP SWITCH #4 in the UP position. This is the default/factory setting.

My Installations

Washing Machine

The photo below illustrates my washing machine installation. I am using this project to protect my washing machine from an accidental flood. I am using the older Furman MP-20 model as well as the older Floodstop controller. Shutting off the water supply alone via the Floodstop valve is not enough to protect against a washing machine flooding disaster. There are two significant risk factors, A leak could be detected when the washing machine is trying to empty it's contents, for example if the drain line were blocked. Without powering off the washing machine, it would continue to pump all its contents out and potentially cause a flood. So this project will ensure that both the supply water and power are cut off to the washing machine to prevent it from flooding.

Hot Water Heater

The next photo is of my tankless hot water heater installation. I am using this project to protect my basement from accidentally flooding if the water heater were to leak. I am using the older Furman MP-20 model and the newer (V4) Floodstop controller. The tankless hot water heater contains an internal recirculation pump and the installation also has an external condensate pump. The Floodstop + Furman will shut off these devices if a leak is detected. I wanted to power down both the internal recirculation pump and the condensate pump if any water leak is detected because shutting off the water supply may not be enough to stop a flodding condition.