Why Is My Boiler Still Running When the Thermostat Is Off?

Boilers are an excellent way to provide your home with hot water. Energy efficiency, speed, and reliability: boilers offer all of these features and so much more. But it’s not unheard of for boilers to act seemingly on their own accord, so many homeowners ask, “Why is my boiler still running when the thermostat is off?”

why is my boiler still running when thermostat is off

Hodgkins’ professional heating repair experts at JC Heating & Cooling are here to explain why boilers run even when their thermostats are set to off. 

Broken Thermostat

When homeowners ask, “Why is my boiler still running when the thermostat is off,” many assume that there’s a thermostat issue. It makes sense: if you set your thermostat to off, but it isn’t affecting the boiler’s functioning, then it’s probably not working.

But there’s much more to broken thermostats than most people assume. Thermostats are much like a power switch. They measure the water temperature and check if it matches the pre-set temperature. If it’s too high, it turns off the heating. But if it’s below the desired temperature, then it will keep heating your water.

Sometimes, this mechanism breaks down and tells your boiler to keep running as if it hasn’t reached your desired temperature, even if it actually has. So you’ll want to disconnect a faulty thermostat and replace any old wires with new, fresh replacements. If that doesn’t work, it’s probably a deeper issue that requires professional assistance.

Temperature Changes

Indoor temperatures can affect your boiler’s performance. If temperatures outside the unit quickly drop, for instance, your thermostat might suspect that it needs to turn on to warm your water, even if the water is already sufficiently hot. 

Try placing foam rolls on your boiler’s plumbing pipes or keeping it on a frost cycle. You can also adjust your home’s air conditioning system to prevent rapid temperature changes where your boiler is located. Many homeowners who ask, “Why is my boiler still running when the thermostat is off,” don’t think of these simple steps.

Faulty Wiring

When their boiler continues running even after turning off the thermostat, it’s common for homeowners to overlook their boiler’s wiring. Boilers, whether they use gas or electricity, rely on many wires and fuses to function properly. These wires can become old, crusty, and frayed, preventing reliable electricity exchange from occurring.

Before inspecting your unit’s wiring, check your circuit breaker box. Switch the boiler’s power off to prevent shock, and turn off any other switches that could affect your boiler. Then, you can identify and replace any blown fuses or wires as needed. 

Heating elements, in particular, are tough to fix and require a licensed contractor’s help. Experienced boiler professionals can help get your furnaces and boilers working again.

Water Pressure

High water pressure is a serious problem. When your boiler’s water is highly pressurized, it won’t run properly, and your thermostat might think your water needs more heating than it actually does. As a result, it will work harder to try and compensate.

Fixing your unit’s water pressure doesn’t have to be difficult, however. Simply inspect your unit’s diverter valves for any blockages or debris, making sure that they’re wide open for optimal water pressure. You can also adjust your home’s water pressure directly using its water pressure knob.

Valve Issues

Boilers rely on motorized valves to function effectively. These valves, in turn, have little pieces known as microswitches. These switches might be small, but they’re crucial for controlling your boiler’s operations.

Water valves might not be a method of heating, but they affect the flow of water inside your system, which, in turn, affects the heating cycle. Sometimes, however, these valves close even when the microswitches are set to “on.”

So whether your valves are closed or if they are rapidly opening and closing, they can cause your boiler to run. 

Contact the Best Heating Services in Hodgkins

Our team of experienced experts at JC Heating & Cooling offers the best heating service in Hodgkins, IL. We specialize in heating maintenance, repairs, and installation projects, prioritizing quality service at affordable rates that will improve your home’s water and air quality. 

Scheduling boiler repairs as soon as you notice a problem is essential to prevent the issue from worsening. Our professionals use state-of-the-art equipment and years of industry experience to deliver reliable services, no matter the type of boiler system your home has. 

If you’re still asking, “Why is my boiler still running when the thermostat is off?” or if you have any other heating questions, call us at (708) 968-3131.