Venta technician diagnosing a York furnace that is not heating in Los Angeles

York Furnace No-Heat · Ignitor · Flame Sensor · TM9V Board

York® Furnace Not Heating in Southern California

A York furnace that runs but will not heat is almost always a worn hot-surface ignitor, a fouled flame sensor, a draft fault, or a control board — including the 2012–2016 TM9V cohort board failure a generalist misses. The blower pushing room-temperature air means the control is calling for heat but the burners are not staying lit. Venta is an independent York, Coleman®, and Luxaire® furnace repair-and-installation contractor who reads the green/amber/red LED code, confirms on the meter, and quotes the actual part across the lineup (TM9V modulating, TM8V single-stage, plus the matching Coleman and Luxaire furnaces) in Los Angeles, Orange, San Bernardino, Riverside, and Ventura counties. Flat $89 diagnostic, credited to the repair. CSLB #1138898 (C-20).

Phones answered 24/7. Same-day dispatch in business hours, typical arrival 2–3 hours. Call (424) 766-1020.

No-heat is the call that defines a SoCal winter: the furnace ran fine in March, sat idle all summer, and now refuses to fire on the first cold night in November. Most are inexpensive single-visit fixes — with one York-specific cohort issue worth knowing. This page is the York-specific companion to our general furnace repair service and our York furnace repair page. Common failure modes have dedicated guides: ignitor replacement, flame sensor, won’t ignite, limit switch, pressure switch, inducer motor, and gas valve.

Why a York furnace stops heating

  • Hot-surface ignitor wear — the most common no-heat fault. Blower and inducer run, no flame; after three failed trials, a seven-red-flash lockout. $245–$485 installed.
  • Flame-sensor fouling — the furnace lights, then shuts down after 3–7 seconds because a dust-coated sensor cannot prove flame. Clean or replace, $185–$295.
  • TM9V 2012–2016 ignition-control-board cold joints — intermittent ignition that clears when the board cools. Full board replacement, $385–$685.
  • Draft / pressure-switch fault — the inducer cannot prove safe venting (two or three red flashes), often a clogged condensate trap or a weak inducer.
  • Open high-limit (four red flashes) — overheat from restricted airflow: a clogged filter, closed registers, or a dirty blower.
  • Gas-valve failure — less common, $385–$685.

The TM9V board trap

The York-specific furnace failure worth knowing: on 2012–2016 TM9V variable-speed furnaces, the integrated control board develops micro-cracks in the solder joints around the hot-surface-igniter relay from years of thermal cycling. The symptom is intermittent ignition that clears itself by the time the technician arrives — the board cools and the joint reconnects. A contractor who does not know this cohort replaces the igniter, then the flame sensor, then the gas valve, and never solves it, because the fault is the board. The fix is a full control-board replacement, $385–$685. We test for it deliberately on any intermittent-ignition TM9V from that window. The full ignition chain is in our furnace ignitor failure guide.

Read the York LED code first

York furnaces report faults on a control-board LED that flashes green, amber, or red, viewed through the access panel. Green is normal status; amber covers normal call states and soft airflow/vent warnings (a rapid amber flash means low flame sense). Red is a hard fault you count: two red is a pressure switch stuck closed, three red is a pressure switch stuck open, four red is an open high-limit or 24V fuse, five red is a rollout or auxiliary limit, and seven red is an ignition lockout. The exact map can vary slightly by board generation, so the legend on the blower door is the authoritative key — we read it against that legend and confirm on the meter. The full reference is on our York error codes page. Do not keep resetting a furnace that locks out repeatedly.

The first-cold-night pattern

An LA-basin furnace runs 200–500 hours a year against 1,500-plus in a cold climate, and the long idle stretch from April to October is where no-heat breeds: dust on the flame sensor, a tired ignitor, stiffened inducer bearings, and the TM9V board solder joints cycling through expansion and contraction. The first November cold snap asks an untouched furnace to fire cleanly, and the predictable failures surface at once. Mountain installs in Big Bear and Wrightwood run real heating hours and fail on a different curve. Either way, fall maintenance in October is the cheapest insurance; the cold-air and ignition chains are in our furnace blowing cold air and furnace ignitor failure guides, and older standing-pilot units in pilot light won’t stay lit.

York no-heat repair pricing

Flat-rate, parts and labor, from our SoCal service tickets. Diagnostic is $89 ($149 after-hours), credited to the repair if you proceed:

York furnace repair Typical cost
Diagnostic (waived with repair)$89 / $149 after-hours
Hot-surface ignitor$245–$485
Flame sensor (clean or replace)$185–$295
Gas valve$385–$685
Ignition control board (TM9V)$385–$685
Blower motor$485–$895
Draft inducer motor (TM9V)$580–$1,100
Heat exchanger (crack — we quote replacement)$1,500–$3,500

York heat exchangers on TM9V and TM8V furnaces carry a 20-year limited warranty to the original owner; other parts are 10 years when registered within 90 days. Labor is separate. These are the same flat rates on our York furnace repair page.

Repair or replace your York furnace

Under 10 years old with a repair under roughly a third of replacement cost, repair it — an ignitor, inducer, or TM9V board on a furnace with cabinet and heat-exchanger life left is well worth fixing. Over 15 years, or any age with a cracked heat exchanger, replace it: a cracked exchanger is a carbon-monoxide path, and we red-tag and shut the gas before leaving. We give you the repair figure and a written replacement quote side by side. See furnace installation when replacement is the call.

Coleman and Luxaire furnaces

Coleman and Luxaire furnaces are the same Johnson Controls equipment under different shields — same integrated control board, gas valve, inducer, and ignition components, cross-referencing one-to-one (including the TM9V-equivalent board cohort). We service all three with the same meters and warranty channels. For the cooling side of a York system, see York AC repair, and the full lineup on our York brand page.

Frequently asked questions

Why is my York furnace blowing cold air or not heating at all? +
My York furnace will not ignite — what is the most common cause? +
My York furnace lights then shuts off after a few seconds — what is that? +
How much does it cost to fix a York furnace that is not heating? +
My TM9V ignites intermittently and works when the tech arrives — what is wrong? +
Should I keep resetting my York furnace when it locks out? +
When does a no-heat York furnace mean replace instead of repair? +