Furnace Repair in Hermann, MO

Furnace not working? Match the symptom to the likely fault

Eight symptoms cover most no-heat calls. Tell us which one you have, because it decides which parts we bring.

Why do furnaces fail during a Hermann freeze season?

Long run times find weak parts. Hermann logs about 116 freezing nights a year (BestPlaces), with winter lows averaging near 24°F, so a marginal igniter or a tired blower motor rarely makes it to spring.

• Older houses, older installs. The median Hermann home dates to 1956, and ZIP 65041's largest groups come from the 1970s and 1980s. Some of those furnaces sit on small return ducts, and a starved return can trip the high limit on a long cold run.
• Propane past city limits. Inside town, the municipal Hermann Gas System feeds the furnace. Outside it, a farmhouse may rely on a tank, and a low tank in a cold snap can look exactly like a dead furnace.
• Snow and condensate. High-efficiency units vent through side-wall PVC. Drifts block those pipes, and a frozen or clogged drain line shuts the furnace down.

How we trace the fault before touching a part

We follow the furnace's own sequence, because it tells us where it stopped. A gas furnace runs a fixed order: call for heat, inducer, pressure switch, igniter, gas valve, flame proved, blower. The step that fails is the step we test.

That is why we read the board's light code, check voltage at the thermostat circuit, measure the igniter and read the flame sensor signal before ordering anything. Guessing costs you money. A pressure switch and a control board can throw similar symptoms, and they are very different bills.

Igniter replacement, blower motor repair and the bigger calls

Most failures have a clear fix, and a few deserve a second look at the numbers.

• Flame sensor cleaning. Quick and inexpensive. It may return if the combustion air is dusty, so we look at why it fouled.
• Igniter replacement. A wear item, and the right call on most furnaces. Oily fingers shorten a new igniter's life, so it goes in carefully.
• Blower motor repair. A failed capacitor is a small fix. A failed motor costs more, and on an old unit it deserves a price check.
• Control board. Worth doing on a sound furnace, after we confirm the board is the fault and not a shorted part damaging it.
• Heat exchanger. The biggest repair, and a safety matter. Past about 15 years, compare it with replacing the furnace.

What furnace repair in Hermann includes, step by step

You should expect the same deliverables from any contractor: a named fault, a price before work, and a test afterward.

1. We hear the symptom from you and check thermostat settings.
2. We inspect the filter, vents and condensate drain.
3. We run a heat cycle and watch where the sequence stops.
4. We test the suspect part and the safety controls around it.
5. We look over the burners, venting and heat exchanger access.
6. We name the failed part and give you the price before any repair starts.
7. We make the repair, run full heat cycles and confirm temperature at the registers.

Most repairs finish on that visit if the part is on hand. If it is not, we tell you what is on order and what to do meanwhile. A photo of the furnace data plate helps us check parts first, especially on a long drive out to a farm.

What moves a furnace repair bill?

Part, access, furnace age and season move the bill most. Labor in Angi's St. Louis figures, checked November 2026, is $125 to $150 an hour, with a circuit board at $273 to $2,000 and a heat exchanger at $113 to $3,000. Those are regional numbers, not our prices. Older furnaces can need special-order parts, so a sound repair may take longer to source. Ask us for a clear, upfront quote.

Why Brian Grannemann Services for furnace repair?

• Jo M. reports that Brian came out on an evening during one of the coldest days in decades to repair a faulty furnace.
• Donna M. describes work that "uses every safety precautions to protect his clients," which is what a gas appliance demands.
• Stephanie H. says Brian "shows up when promised, completes the work correctly the first time."
• We opened in Hermann in 1998 and keep a staffed office on E 10th St.
• We also handle electrical and plumbing, so a bad circuit or a drain problem does not mean a second company.

Keeping the next no-heat call away

Change the filter, keep vent pipes clear of snow and test your CO alarms. A fall furnace tune-up catches a fouled sensor while the weather is still kind. If the house loses heat in a hard freeze, open the cabinet doors under sinks and let faucets drip, then follow our emergency furnace repair steps.

We take furnace calls across the Hermann area, including Berger, Morrison, New Haven and Owensville. Call (209) 563-1270 and tell us the symptom.