If your home has radiant heating, then there are two or possibly three separate controllers for the boiler and your heating. Homes with underfloor radiant heat will generally have two controllers. The boiler itself has a controller that measures the temperature of the water inside the unit to ensure it is heating to the correct temperature.

The second control is the boiler thermostat, which measures the temperature of the home to signal the boiler to start heating and the circulating pump to send water through the system. Once the temperature reaches whatever the thermostat is set to, the thermostat will then signal the boiler and the pump to turn off. If your home has room radiators, these will also typically have a thermostatic radiator valve on each unit that controls how much water flows through the unit and how hot it gets.

If the thermostatic radiator valve is bad, it will only affect that room. If either the boiler controller or the boiler thermostat is bad, your whole home will be affected. Knowing if your boiler controller and boiler thermostat are working correctly isn’t always easy. Many of the issues that can result from bad boiler controllers can also be due to various other issues with the boiler. Nonetheless, there are some signs that can help you know when you need to have your boiler controllers inspected and possibly repaired or replaced, and here is what to look for.

Boiler Won’t Turn On

If your boiler won’t turn on when your thermostat is calling for heat, the first thing to do is make sure the system has power. Even if you have a gas boiler, it won’t run without electricity. For this reason, you’ll want to start by making sure the circuit breaker isn’t tripped. If the system has power, you will then want to change the batteries in the boiler thermostat, as it could be that they don’t have enough charge to signal the boiler to run.

After replacing the batteries, try turning the heat up 10 degrees higher than your normal setting to see if the boiler will now start. If it does start when you turn the heat up, it indicates that the problem is with the boiler thermostat. In this case, the thermostat may need to be recalibrated or replaced. There is also a chance that you may need to have your thermostat moved to a different location, as it could be in a warmer area where it can’t accurately gauge your home’s real temperature. Another possibility is that the inside of the thermostat is coated in dust, as this can prevent it from reading the temperature properly. For this reason, we’d also recommend taking the cover off your thermostat and cleaning it out using compressed air to see if this fixes the problem.

If the boiler still doesn’t turn on, you’ll then want to check if the receiver is working correctly. The receiver usually sits next to the boiler and is what receives the signal from the thermostat. It tells the boiler when to turn on and off. When working correctly, the receiver should have a green indicator light. If the light is off, it indicates that the thermostat and the receiver aren’t communicating.

If the receiver isn’t working or your boiler still won’t turn on, you’ll need to have the boiler and thermostat inspected. It could be that the thermostat is bad, or there is some internal issue with the boiler preventing it from running. Another possibility is that there is an issue with the electrical wiring in the boiler or the wires that lead from the thermostat to the boiler. If your power has gone out recently, you may also need to reset the boiler, as some units need to be manually reset any time the power goes out. There is also a chance that your boiler has simply failed due to age or some other issue and needs to be replaced.

Boiler Runs Almost Constantly

Your boiler generally shouldn’t ever run constantly, even on extremely cold days. When the weather is much colder, it could run quite frequently and for longer than usual, but it still shouldn’t stay on all the time. If the boiler does run most of the time, it typically means that either the boiler controller is bad or there is some issue preventing the unit from heating properly. A bad boiler controller can sometimes make it so that the unit never heats the water as high as it should. Similarly, the unit’s burner can also have various issues that prevent it from creating enough heat.

Radiators Take Much Longer to Heat Up or Never Get Very Hot

These problems are typically directly related to the previous one. If your radiators start taking forever to finally get hot or never get as hot as they normally would, it means that there is an issue with the boiler controller or some other problem preventing it from creating enough heat. Another possibility is that there is a leak in the system or that the boiler’s internal circulating pump isn’t working correctly, as both can prevent water from circulating through the system properly. If your home has underfloor radiant heating and always stays too cold or takes much longer to heat up, it could also be due to any of these issues.

Temperature Is Too High

An improperly calibrated thermostat can also cause the boiler to heat too much so that your home quickly becomes too hot. This problem can also occur if the boiler controller is bad and can’t sense the water temperature correctly. However, this isn’t all that common, as the boiler should automatically shut down if it gets too hot. If the boiler ever did heat too much, the pressure inside the tank would quickly rise and potentially create a major safety hazard, which is why all boilers have internal switches designed to shut the unit down should this ever happen.

Higher Than Normal Energy Bills

Your heating bills should always remain fairly consistent from month to month and even year to year. While it is normal for heating bills to increase slightly the older your boiler gets, you still shouldn’t ever see a sudden spike in heating costs. If your energy bills do ever spike during the winter, it is a sure sign that you need to have your boiler inspected. In this situation, you can be fairly certain that you have a bad boiler controller, bad thermostat, or some other issue that is causing the boiler to run much longer and use more energy.

Contact the Professionals

If you’re having any problems with your boiler, First Choice Plumbing, Heating & Air Conditioning is here to help. We specialize in boiler and radiant heating systems and can help with any repairs or maintenance. We also offer a full range of other plumbing and HVAC services, including installing, maintaining, and repairing furnaces, water heaters, sump pumps, and air conditioners.

To schedule a boiler inspection or any other plumbing, heating, or cooling service in Metuchen, NJ contact us today.

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