Furnace Repair in Colorado Springs

A sunny 50-degree afternoon in Colorado Springs can turn into a single-digit night when a cold front drops down the Front Range, and that first hard night is when a weak igniter or a dirty flame sensor finally gives out. Best Pro repairs gas furnaces in homes all over the city — Briargate, Northgate, Stetson Hills, Rockrimmon, the Broadmoor area, Old Colorado City — and in Monument and around Fort Carson.

Why altitude matters

At about 6,000 feet, every cubic foot of air holds roughly a sixth less oxygen than at sea level. A gas furnace has to be set up for that: its input is reduced for the elevation, usually through the orifice size or the gas pressure, and some models also need a high-altitude pressure switch. The installation manual says what your model requires. Two things follow:

• Pressure switch errors come easily. Before the burners light, the inducer fan has to pull enough draft to close the pressure switch. Thin air leaves it less margin, so a small extra restriction — snow in a vent pipe, water in the switch hose, a dirty inducer wheel — can be enough to stop the furnace.
• A furnace that was never set up for the elevation burns rich. The signs are soot on the burners, flames rolling out of the burner box and tripped limit or rollout switches. If the flame tells us the setup is wrong, we’ll say so.

What the symptoms point to

Most furnaces flash a code on a light inside the cabinet. Count the blinks through the window in the panel before you switch the power off — cutting the power clears the code.

• Nothing happens at all. The thermostat (dead batteries are common), a tripped breaker, the furnace service switch that looks like a light switch near the unit, or the door safety switch on a panel that isn’t seated.
• The inducer runs, nothing lights. The pressure switch circuit: the vent pipes, the switch hose, the inducer or the switch itself.
• The igniter glows, but there’s no flame. The gas valve or the gas supply.
• The burners light and go out within seconds. Usually the flame sensor. A coated sensor can’t prove the flame; cleaning or replacing it is a quick repair.
• Warm air, then cold air, or an early shutdown. A failing blower motor or capacitor, or a clogged filter that lets the furnace overheat until the limit switch opens.
• A boom when the burners light. Delayed ignition: dirty burners or low gas pressure let gas collect before it lights. It stresses the heat exchanger, so have it checked soon.

Snow, wind and the vent pipes

A high-efficiency furnace draws combustion air in and pushes exhaust out through two white plastic pipes on an outside wall or the roof. Wind-driven snow packs into the intake, and on a long cold night the exhaust can grow a cap of frost. To the furnace, either one looks like a draft problem, and it locks out. After a storm, clear the pipes by hand — don’t chip at the ice with a tool, the plastic cracks easily. These furnaces also drain water through a condensate line, which can freeze where it runs through a cold garage or outdoors. Monument and Woodmoor sit on the Palmer Divide at close to 7,000 feet and usually get more snow than the city, so check the pipes there after every storm.

Gas and carbon monoxide

If you smell gas, don’t touch the thermostat or the light switches. Leave the house and call your gas utility — Colorado Springs Utilities inside the city — or 911 from outside. Colorado law calls for a carbon monoxide alarm within 15 feet of every bedroom in homes with gas appliances; if one goes off, get everyone outside and call 911 instead of resetting it. On every repair we check the burners, the venting and the heat exchanger for signs of trouble.

Before the heating season

A tune-up in September or October costs less than a no-heat call in January. We clean the burners and the flame sensor and check the igniter, the inducer and pressure switch, the blower, the filter, the condensate drain and the venting. HVAC service call and repair prices are on our prices page.

Gas fireplace acting up too? See fireplace repair. For cooling, see air conditioner repair — the AC uses the same blower.