The Tank Blanket RV Holding Tank Heater - 40 Gallon - DC - 12" x 30" is an auxiliary heating device designed to be applied to the exterior of a holding tank in your RV, trailer or camper. This RV accessory acts as an electric heating blanket for various types of water tanks.

Made of a laminated heating element, thermostat switch and rubberized backing material with an outer aluminum layer
Inner layer made of Pressure Sensitive Adhesive that allows it to stick to the tank
Helps prevent freeze ups
Easy peel and stick mounting
Adhesive is strong enough to withstand heavy use and weather
Thermostatically controlled
Energy efficient
Temperature Rating: 40 degrees ON/58 Degrees OFF
In higher temperatures it is recommended to remove power from heater
Never use when tank is empty
Functions on DC/13.6 power
Watts: DC/165
Ampere rating: 12.0 DC
Dimensions: 30" L x 12" W
Limited 90-day manufacturer warranty
Made in USA

Tank Blanket RV Holding Tank Heater - 40 Gallon - DC - 12" x 30"

How Tank Blanket works: Once installed on your RV water tank, the thermostat switch controls the flow of electrical current to the heating element. The thermostat switch will turn on the heater at approximately 40 degrees F and will turn off the heater at approximately 58 degrees F. Because aluminum is a good insulator, the backing of this heater will hold the heat in. This process will keep the liquid in the tank from freezing during harsh weather.

How to install the Tank Blanket:

STEP 1: Determine best location on your tank.
- Pick a placement such that the tank blanket will be in maximum thermal conductivity with the tank contents. Because tanks differ in shape and size, find the location on the bottom of the tank where the internal liquid is most likely to be present.The goal is to transfer the heat from the tank blanket, through the wall of the tank, to the liquid inside the tank. Since the heat is transferred by conduction "all elements in contact" the ideal position is to install the tank blanket flat against the bottom of the holding tank.
STEP 2: Clean location
- Using a rag soaked with alcohol or mineral spirits and clean an area slightly larger than the heater at this location of the tank.
STEP 3: The RED DOT
- Find the RED DOT on the heater. The BUMP under the RED DOT is the control thermostat. The thermostat must be in a location near the lowest point of the tank area where the liquid is present.
STEP 4: Test the position – DO NOT REMOVE THE ADHESIVE BACKING
- Hold the heater in place on the tank. Orient the RED DOT to an area near the lowest point of the tank. Check the routing and clearance of the power wires of the heater.
STEP 5: Remove the 2 backing papers LARGE and SMALL
- Remove the LARGE backing paper from the foil backing. Remove the SMALL backing paper from the heater assembly.
Step 6: Stick the heater to the Tank – CAUTION: THE BLACK ADHESIVE IS EXTREMELY STICKY
- Carefully press the heater onto the tank at the desired location. Using a soft cloth, press firmly and smoothly over the entire surface of the aluminum foil of the heater. Work out any bubble or gaps with your fingertip. Press your fingertip along the edges and where the power wires come in to be certain a good seal is made at these locations. The RED DOT, press your fingers along each side of the RED DOT(thermostat) to be certain that the thermostat and the area around the thermostat BUMP is snuggly adhered to the tank.
STEP 7: Connect the power
- Route the power wire to the appropriate power source, use tape or zip ties to keep the wire safely in place along the chassis and frame. Make all necessary electrical connection to a fused power source.

Usage suggestions: Please read

Engage the electrical power to the unit when weather conditions denote that freezing conditions are prevalent. The thermostat switch controls the flow of electrical current to the heating element. The thermostat switch will Turn ON the heater at approximately 45 degrees F ( + - 5 degrees) and will Turn OFF the heater at approximately 60 degrees F ( + - 5 degrees). However, there are many cool days when the temperature is less than 45 degrees and freezing conditions are not imminent. Therefore, use common sense, and unplug or remove power from the heater until necessary. Otherwise, the heater will try to raise the tank temperature to 60 degrees and waste energy unnecessarily when freezing conditions are not prevalent.
The Tank Blanket is an aid to prevent the liquid in your tank from freezing. The heat produced is spread over a flat area by the heater and contained in by the rubberized and aluminum backing. If your tank is exposed to the elements (some tanks are inside the vehicle), some type of additional insulation may be necessary to retain the heat to the tank liquid. Wrapping your tank with some type of insulation found at the local “home” store is advisable for optimum thermal efficiency

Usage warning: Please read

Never engage electrical power to the heater if the tank is empty.If you drain your tanks for prolong storage and still provide power from a land line or other sources for functions such as lighting or battery charging in the stored vehicle then disconnect power to the tank heater. Otherwise, if power is still active, the heater will turn on if the temperature reaches 45 degrees and try to heat the air in an empty tank. In this instance there is no liquid in the tank to absorb the heat from the unit and the heater may become very hot.

Additional wiring Instructions ONLY for 12 Volt DC Tank Blankets:

The 12 volt DC heaters use from 5 amps to 11 amps of current depending on the model. The DC Tank Blankets comes with 5 feet of #14 wire attached. The National Electrical Code standard rating for 14 gauge copper wire is 15 amps. If you need to add additional wiring, then be certain to use 14 gauge copper wire when wiring the tank blanket to the vehicle. Also, be certain that this wiring is connected to a 15 amp fuse in the vehicle and that if a toggle switch is used to control the power to the Tank Blanket that it is also rated for 15 amps capacity. Proper wiring is important, you must use the appropriate size connecting wire for the application, use 14 gauge or heavier wire.

Note: The calculated values for amperage in the table use 13.6 volts, as 12 volt automotive battery voltages range from 12.6 volts to 13.6 volts dependent on the state of charge.