A Guide on Installing Electric Baseboard Heating: Illustrated Instructions

1

To determine the room's size in square feet, multiply the length by the width in feet.

2

Identify the type and quantity of windows. Older single pane windows lose heat more quickly compared to newer double or triple glazed windows, which effectively separate different air temperatures on each side.

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3

Determine the number of exterior walls in the given space.

4

Determine if the exterior walls and the space directly above and below the room have insulation. A space located above a basement or with insulated floors under an attic is considered to have insulation.

5

Check if there are any doors leading outside from this room.

6

Calculate a baseline for the total heat required in watts to warm the space. For homes built since the 1970s, most spaces require 10 watts per square foot. For example, a 12-foot by 12-foot room has an area of 144 sq/ft. Assuming a ceiling height of less than 8 feet, this room would be comfortably heated with 1500 watts of heat. To achieve this, a total of 6 feet of "standard density" baseboard heaters should be installed. Standard density heat has a rating of 250 watts per foot. Another type of heat, known as "high density" (HD), provides more heat with a smaller footprint but does not heat quicker or operate for less time.

7

Determine the additional watts of heat to be installed, if any. All the aforementioned factors (window type and number, insulation, etc.) should be considered when purchasing heaters. The baseline wattage may need to be increased by up to 100% if a room is affected by all these factors. It is important to note that installing additional heaters will not increase operating costs. Additional heaters allow the room to maintain the desired temperature on colder days, as opposed to relying solely on the minimum heat (baseline). If only the baseline heat is installed, the room will not be able to replace the lost heat as quickly due to insulation issues or single pane windows. For instance, a room that ideally requires 1500 watts of heat might need as much as 3000 watts if all the aforementioned issues are present. This applies to all types of heating (and cooling in the summer), regardless of the fuel or technology used. Investing in insulation provides affordable benefits in the long run.

8

Decide whether to install a single heater or split the heat between multiple units. In the example room, either a single 1500 watt heater or multiple heaters totaling 1500 watts can be installed. The latter method is suitable for rooms located at the corners of a building with two exterior walls. Generally, heaters are positioned below windows, where most heat loss occurs. Installing additional watts of heat will help the room reach the desired temperature faster compared to having no extra heat.

9

Determine the size and number of circuits required to support the heating load. Installing 240 volt heaters is recommended as it reduces the wire sizes and number of circuits needed. According to the National Electrical Code, a 15 amp circuit can carry up to 12 amps, and a 20 amp circuit can carry up to 16 amps. The total watts allowed to be connected can be determined by simply multiplying the volts by the amps for purely resistive AC circuits (calculations for AC wattage are more complex for inductive and capacitive reactance circuits found in appliances and electronics). For instance, a 15 amp circuit allows for 2880 watts (240 x 12), while a 20 amp circuit allows for 3840 watts (240 x 16). This corresponds to a maximum of 14 and 19 feet of 240 volt, standard density heat, respectively.

Choose a suitable location for the thermostat

Make sure to select an interior wall for the placement of the thermostat. Avoid positioning it above any heat sources or in areas where there is no circulation of air, such as behind doors.

Mark the spot for the thermostat

Measure and mark a spot on the wall, approximately 60 inches (152.4 cm) above the floor, where there are no obstructions like framing members. Cut open the wall using a knife or hand saw.

Provide the necessary wiring

Run a 2-wire circuit, either #14 for a 15 amp circuit or #12 for a 20 amp circuit, of NM type (Romex) or similar cable from the electrical panel to the location of the thermostat. This may involve fishing or snaking the cable between various points, which can be time-consuming. Label this cable as the "LINE" to distinguish it after installation in the thermostat box.

Prepare the heaters

Unpack the heaters and remove the front covers from both ends of each heater. Position the heaters against the wall at the desired location.

Create wiring compartments

Both ends of the heaters have built-in wiring compartments, eliminating the need for additional boxes in the wall. Simply create a small hole in the wall for the cable to emerge and pass through the appropriate connectors at the back of one of the compartments. Make the necessary connections within the compartments.

Connect the thermostat and baseboard heater

Install another 2-wire cable, identical in size to the previous one, between the panel and the thermostat, as well as between the thermostat and the baseboard heater. Designate this cable as the "LOAD" to identify it after it has been installed in the thermostat box.

Daisy-chain between heaters

For multiple heaters, install an additional 2-wire cable between the first heater and the next one. Repeat this process to daisy-chain between successive heaters as needed.

Install cable connectors

Place the appropriate cable connectors in the desired end of the heaters.

Strip and install cables

Remove 8 inches (20.3 cm) of jacket from the cables and insert them into the connectors. Push the cables until 1⁄2 inch (1.3 cm) of the jacket is inside the wiring compartment.

Separate wires

Remove the wirenut from the heater wires in the compartment where the cables entered. Separate the wires.

Connect the black wires

If two cables were installed, connect the black wires of the cables together.

Connect the white wires

If two cables were installed, connect the white wires of the cables together.

Connect the bare wires

If two cables were installed, connect the bare wires of the cables together.

23

Attach the exposed wire(s) to the green screw on the heater or, if available, to the green or exposed wire connected to the heater case using a crimp or screw.

24

Attach one of the loose heater wires (it doesn't matter which one) to the black wire(s).

25

Connect the remaining loose heater wire to the white wire(s).

26

Ensure that the wirenut in the wiring compartment at the opposite end of the heater tightly secures the wires together.

27

Fasten the heater securely to the wall.

28

Secure the covers of the wiring compartment.

29

Repeat this process for each heater.

30

Wire the thermostat. Connect ALL exposed wires and any green wires together using a wirenut. If not already connected, attach a short piece (8") of exposed wire between the exposed and green wires to the green screw on the thermostat.

31

Thoroughly examine the thermostat for any "LINE" or "LOAD" markings.

32

Connect the "LINE" side to the black and white wires of the cable labeled as the "feed" previously. Make sure that each black and white wire from the panel connects to one "LINE" wire or terminal. Under no circumstances should the black and white wires from the panel be connected together.

33

Connect the remaining cable to the "LOAD" side of the thermostat. Connect it in the same manner as the "LINE" side.

34

Carefully coil the wires into the back of the box, avoiding any folding, and secure the thermostat.