Does your building rely on a boiler for water heating, or space heating?
Either way, Reliable Water Services can help you keep your boiler in optimal shape!

Boiler Basics

Boilers have been around for centuries (believe it or not)! Boilers were the original form of water heating—invented to heat water, create steam, and act as a heat source. And they are still used for all those things! Today, most commercial boilers are used for generating hot water in high-capacity applications, like commercial pools and manufacturing facilities, or for space heating in hydronic radiant heat systems, often seen in older apartment buildings, commercial offices, and historic structures.

A boiler usually looks like a big box or a cylinder, with water connections and a ventilation system. A fuel source like natural gas keeps a flame burning inside. The “guts” of a boiler can look a little different depending on the type of boiler and manufacturer, but every boiler contains a burner and a heat exchanger. Depending on the type of heat exchanger, your boiler might be a water-tube, fire-tube, or a high-efficiency condensing boiler. 

Unlike a conventional water heater, boilers don’t store the heated water. A boiler is simply designed to heat the water, which then moves through pipes to the rest of the system. In radiant heating setups, hot water moves through radiators to heat the building. For hot water applications, the heated water usually flows into separate storage tanks, to be used later as needed.

A man in a blue coat and hat inspects a boiler in a large utility space. He is holding a clipboard and pencil.

Prioritizing Boiler Safety

Any time you’re dealing with heat and combustible, pressurized equipment, safety is always a top consideration. Boilers come with risk and are often equipped with more power than a water heater (and thus a higher potential for danger).

In past years, boilers were almost all atmospheric-type boilers, drawing air in from the atmosphere and venting through an exhaust chimney. New, highly efficient boilers often have a sealed combustion system that minimizes heat loss, making them a safer option.

Most states, including Wisconsin and Indiana, require regular inspections and permitting for any business with a commercial boiler. Preventative maintenance will help ensure that your boiler is running efficiently and safely.

Why a Boiler?

So why would you choose a boiler? That depends on various factors, like whether the boiler is to be used for hot water or for space heating. For water heating situations, sometimes a hot water boiler is chosen when a standard water heater can’t be installed because of space or ventilation limitations. Other times, a boiler is the preferred choice because it can generate hot water faster than most tank-type water heaters, and that hot water can then be fed into as many storage tanks as needed to meet the hot water demands of the building.  

When a boiler is heating a building, this is hydronic heating, also known as radiant heating. Many older buildings have boilers because that’s the best method of space-heating technology that existed at the time – and it’s far easier to upgrade an existing hydronic heating system than start from scratch with a forced-air HVAC system.

Several gas boilers are installed in an equipment room of a commercial building.
An outdoor heating boiler is shown on the ground behind a chain link fence.

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