Radiator heat systems were invented back in 1855. Even though this heating technology is among the oldest ones, it still remains relatively effective.
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Radiator heating includes hot water, steam, and electric radiators; the first two receive their heat from boilers and water heaters. Though these heating systems can be quite expensive to install, the thermal comfort provided by such units is as effective as that of gas central heating.
Heating System Types
There is a wide range of heating technologies available on the market.
- Furnaces (forced air distribution systems)
- Boilers
- Heat pumps
- Hybrid heating
- Ductless mini-splits
- Radiant heating
- Baseboard heaters
What Type of Heating System Uses Radiators?
Radiant heating includes two heat distribution systems – hot water radiators and steam radiators.
These systems receive the actual heat from a boiler or water heater, while electric radiators produce heat from the electricity.
A radiator is, basically, a heat exchanger that has hollow tubes filled with steam, water, or oil.
Read: What Is The Best Way To Heat A Large Space?
What Is the Most Efficient Heating System?
The efficiency of a heating system can be described by an AFUE (annual fuel utilization efficiency) rating.
If the system has an AFUE of over 90%, then it is considered to be ‘highly efficient’. The minimum required rating is 80%, but the majority of modern units exceed this number.
Natural gas boilers that heat up water and pump it to individual radiators have an AFUE rating of up to 100%. They are certainly among the most efficient heating systems out there.
How Does a Radiator Heating System Work?
Convection is a process in which heat is transferred due to the movement of a heated fluid. This is exactly how radiator heating works.
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The heated water travels through a system of pipes and gets to individual radiators located throughout the house. The air surrounding the radiators also gets heated up and it then moves around the room thanks to air circulation.
Natural air circulation occurs when a radiator is used. Once the air close to the unit gets heated, it rises, and the cooler air ‘comes in’ and takes its place.
Even though radiators are among the oldest ways of heating a home, they are still extremely efficient and convenient to use as these units are able to heat the room evenly.
Radiators are typically made out of metal because it is great heat conductor. The units are heavily folded – these folds and creases increase the radiator’s surface area so that it is able to come in contact with larger volumes of air.
Fact: in properly functioning radiators the temperature of the water should decrease by around 18 F while it travels from one end of the radiator to the other. If the temperature drop is bigger, then the water is flowing too slow.
What Are the Different Types of Radiators?
Let’s take a closer look at hot water and steam radiators.
- Hot water radiators
The systems of this type have an inlet and an outlet (the inlet takes the water in and the outlet lets it out). The water is heated up in a water heater (however, it never reaches its boiling point).
Then the H2O gets pumped from the water heater through the pipes and the radiators. As the water passes through the system, it starts losing its heat.
Once it becomes too cool to continue heating up the house, the water returns to the heater. The cycle gets repeated every time the temperature in the building needs to be increased.
Usually, such systems are connected to a thermostat, so the cycle starts automatically once the temperature drops to a certain point.
- Steam radiators
A steam radiator is connected to a boiler that heats the water up until it turns into steam. The steam doesn’t need to be pushed around like water; it simply travels through a vertical pipe to the radiator where it gives off its heat.
Once the steam becomes cooler, it turns back into water which returns through the pipe into the boiler. The cycle then repeats until the desired temperature is reached.
Read: Gas Heater Vs Electric Heater – Pros And Cons
Is Radiator Heating Expensive?
How much it is going to cost you to run radiator heating depends on a lot of factors – the type of system, the desired temperature, the quality of insulation in your house, the size of the house, and so on.
In a nutshell, you’ll be paying for the operation of a boiler or water heater. Electric radiators, in their turn, work by using electricity directly.
It is relatively easy to calculate how much it is going to cost you to run radiator heating per day.
For example, if you have an 800W electric radiator and you plan on using it for 5 hours per day, then the average daily cost is going to be:
The radiator’s output (kW) x hours x the cost of kW/h )according to the electric tariff)
0.8 kW x 5 hours x 10.53 cents (US national average) = 42.12 cents
However, the chances are high that your electric radiator won’t be working non-stop for all 5 hours. If the system has a thermostat, it will be turning on and off, so the running cost is going to be even lower.
How Much Does It Cost to Install Radiators in a House?
Hot water radiators are the cheapest – $100-$1.000. An electric radiator is going to cost you anywhere between $200 and $1.500 and steam radiators can cost you up to $2.500.
The size of the radiator, the style, material, heating element, and even orientation are going to impact the cost.
Here are the average costs of plumbed models with different BTU outputs.
| Size (British Thermal Units) | Average Cost per Unit (hot water and steam) |
| 3.000 BTUs | $200-$500 |
| 7.000 BTUs | $500-$700 |
| 9.000 BTUs | $500-$900 |
| 12.000 BTUs | $600-$1.200 |
The cost of an electric radiator is going to depend on its wattage.
Vertical radiators and the units made out of stainless steel are, typically, more expensive.
Be prepared to pay around $200-$400 for the installation of a new radiator (the cost is for labor only).
Read: Is Radiant Heat Cheaper Than Forced Air?
Does Radiator Heat Work Without Electricity?
Radiator heating can’t work without electricity.
Electric radiators need direct electricity in order to function, while hot water and steam units depend on boilers and water heaters that, in their turn, need electricity to run.
Read: What Is Battery Operated Heater?
Can Radiators Start Fires?
A steam or a hot water radiator can’t really start a fire as their temperature never gets too hot. However, such radiators can burn you or damage a fragile material that has been placed next to them.
Electric radiators can actually start a fire. Especially, the older models that can overheat.
Even some newer units can cause, for example, the curtains made out of flammable material to catch fire, if they are close to the radiator.
To avoid that, keep the area around the radiator clear of any objects (this will also help increase the unit’s efficiency). Another thing that you should do is keep the radiators in good working condition.
Any heating system should be inspected by a professional. Ideally, on a yearly basis.
Also, don’t forget to keep the radiators clean. Even though dust won’t exactly cause a fire, it can contribute to a strong, unpleasant smell.
Read: What Is The Most Efficient Heating And Cooling System
How to Clean Radiators?
Turn the radiators off and give them enough time to cool down before proceeding any further.
- Move any nearby furniture away from the radiators and cover the floor underneath the units with newspapers – this will help keep the room clean.
- Use a brush with a long handle to clean the inside of your radiators. Then, use a narrow vacuum attachment to suck up the loose dirt.
- If you have spotted dust in very tight places, use compressed air to remove it.
- If your radiators are painted, you can use a solution of warm water and dish soap to wipe them down.
- Before turning the radiators back on, make sure that they have dried.