Boiler Anatomy 101

The boiler is often the forgotten workhorse of the house -- that is, until it stops working one winter morning and you wake up to a freezing home!
Having a basic understanding of how a boiler works can help you better diagnose the HVAC problem at hand, but boilers are complicated machines. Do you know when you should call a technician? Should you call an HVAC, plumbing, or utilities company?

In case you’ve ever wondered how your heating system works, Warner Service is breaking down the mechanics of a boiler for you.

The functions of a boiler may seem straightforward, as cold water goes in, gets heated, and steam comes out. However, each inner part of this appliance plays an intricate role in making this process happen. Understanding the functionality of these parts, you'll get a better picture of the overall system.

Boilers use inner controlled combustion to heat water. The most important parts are the burner, combustion chamber, heat exchanger, and controls:

  • Burner combines fuel and oxygen in order to create the combustion through the ignition device.

  • Combustion Chamber is where the burner’s mixture and the ignition device come together to create combustion.

  • Heat Exchanger exchanges heat between the cold water and hot water without directly mixing to transfer the heat in the water without directly exchanging the water.

  • Controls regulate the ignition, burner, fuel and air supply, pressure, and water temperature.

You may be familiar with a hot water heater, which differs from a boiler. A boiler heats your home through radiators or radiant floor heating systems while a water heater produces hot water in your sinks, showers, and more.

Types Of Boilers:

Now that you've passed Boiler Basics, it's time to understand what type of boiler you have. In general, there are two main types of boilers: Firetube and watertube boilers.

Firetube boilers focus the hot gases through tubes within a boiler shell that's surrounded by water, which is then heated by the hot gases. The gas passes through the boiler shell at least four times before being released.

In other words, these boilers are moderating pressure while containing water. These types of boilers are typically used for hot water applications because of the thermal conduction properties.

Watertube boilers have vertical tubes rather than horizontal. This changes the functionality of the heating mechanism because steam is created directly from the tubes containing water, rather than tubes heating water.

This type of boiler is more reliable because of the low volume of water contained in the appliance itself. For this reason, they're more common in commercial buildings rather than standard homes.

Furnace Or Boiler?

Many people interchangeably use "furnace" and "boiler", but they're very different. Furnaces use warm air to create a draft around your home, which works well during the summer to create a cooling effect.

However, the winter might be less comfortable with a furnace. A boiler is costlier than a furnace but is more effective at creating a comfortable (not musty) heat. If comfort is high on your priorities list, a boiler is worth the extra money.

Fixing Your Boiler

Now that you're equipped with the understanding of your boiler, you're prepared to fix it should anything happen. Many common problems occur with boilers, and it's fully understanding the problem that's the first step to getting rid of it.

Common cues to look for when identifying a heating problem include checking the pilot light for a blue color. If a yellow- or orange-colored flame appears, you have a heating problem with your appliance. Call a professional in this case.

Listen for certain sounds. A banging or tapping boiler means a heating problem. These sounds are normally complemented by a lack of steady pressure, which means the pressure build-up in the boiler is too much.

While it's advised to call a professional when dealing with a boiler, some problems can be self-diagnosed and resolved.

  • Gas Supply. Try other gas-powered appliances in your home. If you don't have any, ask your neighbor if they're having similar issues. If this is the case, call your gas provider -- not a plumbing service.

  • Power Supply. If your boiler is plugged in but not powering up, it may need to be reset. Set a time for your boiler to power up and see if it complies.

  • Water Supply. If you see an active water supply, double-check the pilot light. If it's out, light it yourself. Be sure to follow the instructions in the user manual when self-igniting.

  • Pressure. Double-check the pressure. Most boilers should fall in the 1.0 to 1.5 range. Follow the instructions in the user manual for refilling the gas supply.

Now that you know a little more about your home's boiler, why not learn how to take care of it? Check out our checklist by below:

Download the Boiler Maintenance Checklist Today