There's No Heat in My House: Here's What to Do

The Short Answer Is: If a homeowner discovers their furnace isn't working and there's no heat in their home, they should start by checking the thermostat settings to ensure they're set to heat and at the desired temperature. Next, they should inspect the furnace for any visible issues, such as a tripped circuit breaker or a pilot light that has gone out, and address them if safe to do so. If these steps don't resolve the problem, it's essential to call a licensed HVAC technician for professional diagnosis and repair to ensure the heating system is restored promptly and safely.

No heat is cause for concern for Louisville homeowners, and many worry the issue is caused by a complicated malfunction. Sometimes that’s the case, but other times, a simple error is to blame. When you know how to troubleshoot a no-heat issue, heating is often able to be restored without a service call.

The NATE-certified technicians of Jarboe’s Heating, Cooling & Plumbing share our No Heat Checklist and the steps to take to troubleshoot your furnace, heat pump, or boiler. If you have no heat, try these tips before you give us a call for heating repair.

The No Heat Checklist

Simple errors have the power to stand in the way of comfort at home. When you have no heat, your first thought is typically to call for heating repair, but there are many troubleshooting steps you are able to perform to restore heat on your own.

We recommend our Louisville homeowners run through the No Heat Checklist before they call. Sometimes, it’s just a minor issue that leaves you without heat. These issues are easily resolved, and troubleshooting them yourself saves you the expense and the wait of a service call. Try the No Heat Checklist first, and if you still have no heat, then give us a call.

Thermostat Troubleshooting

When your home has no heat, the place to start troubleshooting is at your thermostat. The brains of the operation, your thermostat communicates with your heating system and tells it your home is ready for a heating cycle. A no-heat issue isn’t always caused by your heating equipment – thermostat malfunctions and settings errors are common causes.

Verify your thermostat has power. Dead batteries are a common cause of a no-heat surprise. If the thermostat’s display does not come on, check for power issues. Replace batteries, and if your thermostat is hardwired, check the breaker panel to see if its circuit breaker has been tripped and reset if needed. If your thermostat doesn’t come back on, you may need a new one – call us for repair.
If the thermostat is on, double-check that it is set properly. Heat mode needs to be selected, not cool. Fan mode needs to be set on auto so it runs just during heating cycles – the on mode allows the fan to run constantly, which blows cool air from your vents if the heating system is not on.
For programmable thermostats, verify the date and time are correct and that your temperature schedules are correct. Make sure the thermostat is not in hold or vacation mode, as this interrupts the thermostat’s schedules.
Set the thermostat a few degrees higher than your home’s current temperature – this should trigger a heating cycle if a settings issue was to blame for no heat.

Inspect Indoor Equipment

If you look at your indoor air handler or furnace, it looks like a big metal box. This is the cabinet that holds the system’s essential components. There are access doors that allow technicians to reach components for service. In some systems, these access doors must be completely closed or the system does not turn on.

Inspect your equipment’s access panels to ensure they are secure. Secure open or loose panels in the closed position and see if your heating system is able to run now.

Troubleshoot Heating System Power

Your heating system’s elements use electricity to run – even gas systems have electrical components. If the equipment does not have power, you receive no heat. Verify power through the following troubleshooting steps:

At your home’s electrical panel, make sure the circuits that power HVAC equipment do not have tripped breakers or blown fuses. Reset breakers and replace fuses as necessary to restore power to the system.
HVAC systems have actual on/off switches on or near them. Look on the equipment or on the nearby wall to identify the switch and check that it is set to on. Outdoor heat pump equipment needs checked, too – the switch is likely on the exterior wall of the home, along where refrigerant lines run.

Troubleshoot Airflow Issues

Forced air furnaces and heat pumps overheat when there isn’t enough air moving through the system. This is a safety measure that prevents the equipment from getting too hot. If your system was working but shuts down quickly, airflow issues are a possible cause.

Troubleshooting airflow issues starts at your air filter.

Remove the filter from the system and check its condition.
If the filter is dirty, replace it with a fresh one.
Insert the filter back into the filter compartment – make sure you follow the directional arrows marked on the filter’s frame, as an improperly inserted filter interrupts airflow.
Make sure your filter fits properly within the compartment and is the right size.

Next, you need to make sure air is circulating freely throughout your home. Check all vents and return air grills to make sure they are open and uncovered. Remove any furniture, rugs, or other items blocking them.

Troubleshoot Fuel Supply

Natural gas, oil, and liquid propane heating equipment need fuel to complete the heating process. When there’s no fuel, there’s no heat. Inspect fuel supply to remedy issues that cause the system not to run.

For gas furnaces, check the gas valve on the gas line leading to your equipment – make sure it is opened. Verify that your gas service has not been interrupted in any way.
Older gas furnaces probably have a pilot light, that should be lit at all times. If it goes out, you need to safely relight it. Turn off the gas for 10 to 15 minutes before attempting to relight the pilot – this allows any leaked gas to dissipate. Do not try to relight the pilot if you still smell gas. Follow the owner’s manual instructions to relight your pilot light.
Systems that use heating oil or liquid propane have a fuel storage tank – make sure your tank is filled with enough fuel and schedule a refill if it’s not. Make sure the valve on the tank is open to allow fuel to travel to your heating equipment.

Troubleshoot No Heat from a Heat Pump

Outside heat pump units are exposed to the elements during the winter and ice can form on the cabinet. Too much ice prevents the unit from absorbing heat, so it is unable to work. Ice needs to be melted right away to prevent damage to the system.

A heat pump’s defrost cycle is meant to handle minor frost accumulations on the system, but probably won’t be able to melt significant ice formation. In defrost mode, the system runs in reverse for a short period, which sends heat through the coils to melt any frost. During defrost, the backup heat system keeps the home warm.

If your outdoor heat pump has ice on its cabinet or coils, you need to thaw it.

Turn off power to the heat pump.
Use water to melt away the ice.
Chip off ice deposits gently. You don’t want to use sharp objects or be too forceful, as this could damage your heat pump.
Clear away snow, leaves, sticks, lawn clippings, vegetation, and other debris that have built up around your heat pump. Move any items you stored nearby.
Look at the guttering above your heat pump – is it leaking? Leaky gutters send water onto the heat pump, contributing to heavy ice buildup. Repair guttering as needed.

If you are unable to thaw ice on your heat pump, call for heating repair. Our NATE-certified technicians thaw your heat pump and find the source of the ice so repairs are made to prevent the issue in the future.

Boiler Troubleshooting

Hot water boilers produce condensation during the heating process, which normally exits through the system’s condensate pipe. When ice forms on this pipe, condensation floods the system and it produces no heat because it shuts down. Clear any ice deposits to restore function.

Locate your boiler’s condensate pipe and look around its opening for ice. Ice may also form in pipe bends and elbows.
Pour many buckets of hot water through the pipe until the ice deposit is melted. Never use boiling water – you don’t want to crack the pipe!
A heat blanket or hot water bottle may also be used if hot water is not available – wrap it around the condensate pipe until ice melts.
Reset the boiler before you use it.

If You Have No Heat, Call Jarboe’s

After you troubleshoot your no heat issue with the No Heat Checklist, if you still have a heating issue, give us a call. We are happy to send a technician to make heating repairs and restore comfort in your home. When a technician arrives, tell him or her that you have completed the items on the No Heat Checklist, so we know to move on to more complicated issues.

We offer 24/7 emergency heating service to restore heat overnight, on weekends, and even over the holidays. If you have no heat, contact Jarboe’s today.