How Does a Bathroom Wall Heater Work

Bathroom Wall Heater

How do bathroom wall heaters work, well lets start with a flow. Fan forced wall heaters pull air into the front grille and push across the electric heating element. The fan is the reason wall heaters are so much smaller than baseboard heaters. Baseboard works much slower so the heating element needs a lot more surface area. A 1500 watts bathroom wall heater is only a few inches wide, but a electric baseboard heater is around 8 feet wide to heat the same space.

Electric Bathroom Wall Heater Basics

An electric baseboard wall heater is a type of convection heater. Essentially, an electric wall heater is just like a built-in radiator, but with a slimmer design that doesn’t use up as much space. It is low-profile, easy to install and does not require gas lines, ducts or steam pipes. Because it uses electricity, however, it can be expensive to run compared to other heating methods.

How electric heater works

The electric wall heater is powered by a heating element. A high-voltage electric current is run through a resistor, a type of material that resists the flow of electricity. The resistor turns the electric energy into heat. That heat is then conducted into metal fins that stick out from the heater, which spread the heat into the room.

How the Heat Spreads

Electric wall heaters use a phenomenon called convection to carry heat around a room. The air immediately above and between the fins heats up, which makes it expand and rise into the air. This leaves a vacuum, and more air is drawn in to fill in the empty space. Soon, a continuous air current develops. Air continuously heats, rises and spreads out. Then it cools, falls and returns to the heater. This air current carries heat through the whole room.

Advantages and Disadvantages of Electric Wall Heaters

Electric wall heaters are useful because they can heat a single room without heating up the whole house. This saves a lot of energy if you spend most of your time in one part of the house. They are also easy and inexpensive to install compared to other heating systems. They only take up a little room at the baseboard, so they don’t hog a whole side of the room like traditional radiators. The main disadvantage of electric wall heaters is the expense of running them.

Electricity is almost always more expensive per unit of energy than natural gas or propane–particularly with the efficiency of modern forced air heaters. Basically, an electric wall heater is only a good idea if you want to just heat one part of a house.

A quick BTU Calculator for your home

The following is a quick systems for calculating your home heat load in BTU’s. The more you know about your home the better the guide is. What do mean? Make sure you have all the correct room sizes, and are you sure about you insulation factors. Do you have more windows than the average room? Did you pick the correct outdoor temperature? I made an easy guide for homes with electric heat.

30 BTU/hr. = 8.7 watts

35 BTU/hr. = 10.2 watts

40 BTU/hr. = 11.7 watts

45 BTU/hr. = 13.1 watts

50 BTU/hr. = 14.6 watts

55 BTU/hr. = 16.1 watts

60 BTU/hr. = 17.5 watts

I hope that helps I hope you like the following article on btu’s per square foot.

How Do You Calculate BTUs for Square Footage?

The strength of the heating system in a building is often measured in British thermal units (BTUs), and determining how many BTUs are necessary for a particular building is an art and a science. A typical house should have a heating system that can muster between 30 and 60 BTUs per square foot of floor space. Builders use systems toward the higher end of the range in the colder regions of the U.S. and they use systems toward the lower end of the range in the warmer regions. So, at best, the calculation of the recommended BTUs for your heating system is an estimate, but it is still worth doing.


  • 1 Determine the square footage of your house. If you don’t already know it, measure the length and width of a single room, in feet, and multiply those measurements. Repeat this for each room in the house and add the results.
  • 2 If your home is located very far north in the U.S., consider using a value of 55 to 60 BTUs per square foot of home. If you are more centrally located but north-leaning, consider using 45 to 55 BTUs per square foot of home. If you are more centrally located but south-leaning, consider using 35 to 45 BTUs per square foot of home. If you are located in the deep south, consider using 30 to 35 BTUs per square foot of home.
  • 3 Calculate the total BTUs your heating system should generate by multiplying your square footage by the BTU range you selected in Step 2. For example, if you live in a 2,000-square foot home in the far north, you will need a heating system in the 55-to-60 BTUs per square foot range.

Lower BTU estimate = 55 BTUs/ft^2 x 2,000 ft^2 = 110,000 BTUs

Higher BTU estimate = 60 BTUs/ft^2 x 2,000 ft^2 = 120,000 BTUs

Your heating system should generate between 110,000 and 120,000 BTUs to adequately heat your home. This is a rough estimate, and you should consult a heating professional to obtain a more definitive number.

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