HVAC Repair in Baltimore, MD
Homes here need heat from October through April and cooling from June through September. If your system quits, tell us what it's doing and a licensed contractor who covers Baltimore will get in touch.
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Baltimore runs its system almost year round
Your furnace works October through April, then your AC takes over in June and runs through September. That is 11 months a year one system or the other is on. Winter nights average 28°F, cold enough that the burner cycles on and off for hours to hold the house steady, and each start puts wear on the igniter. Summer afternoons average 87°F, and the compressor runs long stretches to keep up, which is what wears out a capacitor or a run of refrigerant charge over time.
Most homes here heat with gas, so a furnace that will not fire on a 28°F night is not a small thing. Baltimore has also logged 45 damaging wind events and 13 winter storms over the past ten years, and 11% of Maryland households went at least 24 hours without power in 2024. Most systems restart on their own once power is back, but a storm that knocks branches into a condenser or an outdoor unit can leave it needing a look before it runs right again.
- 7 months
- October through April, your system heats
- 4 months
- June through September, it cools
- 28°F
- the average winter night it heats against
- 87°F
- the average summer afternoon it cools against
NOAA nClimDiv, 1991–2020 normals
A new furnace and air conditioner would cut about $160 a year off heating and cooling for a typical Baltimore home.
Estimates for a typical Baltimore home, compared with an older unit built to the previous federal minimum, from EIA household energy data, Maryland fuel prices and NOAA climate normals. Your home will differ.
Repair makes sense when one part has failed.
Replacement makes sense when the furnace's heat exchanger is cracked, the air conditioner's compressor has failed, or repairs keep coming.
Maryland requires HVAC contractors to hold a state license.
Maryland's Board of Heating, Ventilation, Air Conditioning, and Refrigeration Contractors tests and licenses the contractor. That license belongs to the business, not to any one job, so it is already in place before a contractor gets to your house rather than issued for this particular repair.
For a repair to your heating and cooling system, that state license is what stands behind the person doing the work. It says the state has tested this contractor and keeps a record of them, which is the protection you have here.
Sources: Maryland General Assembly · Maryland Department of Labor
- Why is my heat not working?
- The most common reason is a bad igniter or flame sensor, especially if the furnace tries to start and then shuts off. A dirty flame sensor reads the fire wrong and cuts the gas even though the burner is working fine. If the furnace does not attempt to start at all, check the thermostat batteries and the breaker first. Winter nights here average 28°F, so a furnace that short cycles or won't fire needs a contractor look before the next cold stretch.
- Why is my system running but not cooling the house?
- If the outdoor unit and indoor blower are both running but the air coming out is not cold, the coil is likely frozen or the refrigerant is low. A frozen coil usually means airflow is blocked, often by a dirty filter, and ice can build up on the copper lines outside the indoor unit. Low refrigerant means a leak somewhere in the lines, which is not something to top off and forget, since it will run low again. Either way the system needs a contractor to find the actual cause rather than just add refrigerant.
- What can I check before calling for HVAC repair?
- Start with the filter. A filter clogged with dust chokes airflow and can cause both weak cooling and a furnace that overheats and shuts itself off. Check that the thermostat is set to heat or cool as needed and has power. Look at the breaker box for a tripped breaker, and if you have a gas furnace, confirm the gas valve is open. If all of that checks out and the system still is not doing its job, a contractor will need to diagnose it directly.