6 Reasons Why Your Furnace Fuse Keeps Blowing


Sinclaire Enterprises, Inc.

140 South St., Walpole, MA 02081
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During the cold Massachusetts winter, you rely on your furnace to keep you and your family safe and comfortable. Understandably, it’s not a time you want to find out you’re having problems with your furnace and your heating system.

Unfortunately, problems sometimes occur, and since you’re only running your furnace when it’s cold outside, you’re going to discover those problems at the most inconvenient of times. It’s therefore important to know what some of the causes of those problems are, what you can try to do about them, and when it’s time to call a professional like Sinclaire Home Services. Sinclaire Home Services can help you with furnace repairs, furnace installation, or furnace replacement in Milton and other locations in the Boston area.

One of those problems is a furnace fuse that keeps blowing even after you reset it or replace it and reset the circuit breaker. In this article, we’ll look at reasons this might be happening. Although worn or faulty parts might be the first thing you think of, there are actually several other things that can cause a furnace fuse to keep blowing.

Too Much Dirt or Dust

Routine furnace maintenance includes professional cleaning for a good reason. When dirt, dust, and grime build up on a component such as a blower motor. This can result in the motor overheating and burning out. As a result of this malfunction occurring, the unit’s fuse may blow, causing it to shut down. If this is the problem and it isn’t addressed, the shutdowns will keep happening.

In addition to having your unit cleaned, you should be replacing air filters on a regular basis, anywhere from monthly to every 90 days. Particles that accumulate in air filters can migrate to other working parts in the heating system, causing overheating and malfunctions.

Excessive Voltage

When the voltage exceeds a device’s or circuit’s operating limit, a fuse can blow. Chromic overvoltage is usually easy to diagnose, but overvoltage can sometimes be intermittent or sporadic, making it harder to detect.

To avoid overvoltage, simply check your system’s requirements to determine what its minimum and maximum capacities are. If in doubt, hire a professional electrician to perform an inspection and make any necessary adjustments, replacements, or repairs.

Loose Wires or Electrical Shorts

If you reset a blown fuse and then turn the circuit breaker and system back on, only to have the fuse blow again over and over, the problem may be that the unit is not receiving the power that it needs. This issue can be due to an electrical-short or loose wire.

Before attempting to inspect for loose wires or a short, and before attempting to rectify either on your own, always protect yourself from electrical shock by shutting the system off and turning the circuit breaker off. Because of the risks and complications associated with working with electricity and wiring, it’s recommended to have a professional electrician or HVAC technician perform this work. Routine professional inspections of your heating system will also include checking for loose wiring and potential for shorts.

Insufficient Airflow

Low airflow can result from undersized ductwork, a blower motor, or dirty air filters. Poor control applications can also contribute to this. When there is reduced airflow, the system has to work harder to compensate, which risks overworking it, creating an overvoltage situation, and causing a fuse to blow.

Regular maintenance can identify and address these issues. And as we mentioned already, changing air filters on a regular basis is something most people can do on their own fairly easily to help keep their system running smoothly and efficiently.

Leaking Water

A furnace or heat pump can sometimes develop a leak. Usually, the leak comes from an attached or very nearby unit, such as a humidifier. Water droplets or other moisture drizzling from the unit can gather inside the heating unit, causing shorts, a risk of electrical shock, and expensive damage to the system. If you have a situation like this, do not ignore it or procrastinate about addressing it. It’s extremely important to contact a professional service that can take care of this problem that presents safety issues and costly repairs as serious possibilities.

Extreme Cold

A lot of heat pumps have supplemental heating elements to supply additional heat when the efficiency of the heat pump begins to decrease. This typically results from extremely low outside temperatures or extended periods of cold temperatures.

Although this is an excellent feature, which is why many modern systems include it, there can be a downside. The supplemental heating elements can sometimes draw too much power in these situations. That in turn, can cause a fuse to blow or a circuit breaker to trip. In conditions where this is the culprit, fixing it is usually as simple as a reset. Should the problem continue, it’s likely due to one of the other factors we’ve covered or something else.

Get Peace of Mind from a Reliable HVAC Service

When a heating system isn’t functioning correctly and it’s cold outside, comfort becomes a concern and can create a highly stressful situation. At such a time, your primary concern is restoring things to normal as soon as possible. For that, you need to be able to rely on a skilled and trustworthy HVAC service instead of taking chances.

Since 1948, Sinclaire Home Services has been a trusted family-owned business taking care of residential and commercial customers in the Boston region. We provide heating, air conditioning, plumbing, and other home services to take care of your critical systems so that you don’t have to worry about them.

We are fully licensed and insured, and our technicians are professionally trained and certified. Once you get in touch with us, we’ll have a skilled technician out ASAP to diagnose the problem and take care of it.

If you need furnace repair, furnace replacement, or furnace installation in Milton or elsewhere in the Boston area, we have you covered. Contact Sinclaire Home Services today!