Which York control board you have: York used two control board generations with different code meanings
Johnson Controls documents two integrated furnace control generations in the same service letter: the newer UTEC boards and the last-generation White-Rodgers Emerson boards. Ten codes read differently between them, four of those change the diagnosis, and the board part number is printed on the board.
Applies to: York, Luxaire and Coleman gas furnaces. Read this before acting on a York flash code, because two board generations are in service and they do not agree on everything.
What it means
Technical service letter ST-045-09 carries two separate fault code tables, one per generation, and most of the site's York pages are written from the UTEC table. Comparing the two tables line by line, ten counts are worded differently and four of those change what you would actually check. Every page on this site is written from the UTEC table, so on an Emerson board four of them will send you to the wrong place. Six red, nine red and eleven red are identical on both, and those are safe to read either way. The good news is that this is decidable rather than a guess: Johnson Controls prints the board part numbers in the same document, and the number is on a label on the board itself.
Most common causes
- UTEC generation boards: 539617, 542760, 542766, 542767, S1-03102951001, S1-33102954000, S1-33102955000 and S1-33102956000.
- Last-generation White-Rodgers Emerson boards: 265901, 265902, 265903, 265904, S1-33109167000, S1-33109168000 and S1-33109169000.
- The generations were sold consecutively, so the age of the furnace is a rough guide but the part number is the answer.
- Both generations appear across single stage PSC, two stage PSC and two stage ECM variable speed models.
How to diagnose it
- Read the part number from the label on the control board. That settles it in one step.
- Five red flashes is an open rollout on UTEC. On Emerson the same count also covers a blown on-board fuse, which is a minor electrical fault rather than a combustion one — two very different repairs behind one count.
- Ten red flashes is a gas valve energised with no call for heat on UTEC. On Emerson it is gas actually flowing with no call for heat, which is the more serious of the two readings.
- Seven and eight red flashes are a one hour lockout on UTEC and an external lockout on Emerson, which differ in whether the control clears itself.
- Two and three red flashes add "or an inducer error" on Emerson, so a pressure switch reading on that board is not conclusive about the switch.
- The clearest behavioural tell: on a UTEC board a steady amber heartbeat means a call for heat. On a White-Rodgers Emerson board the same condition is one amber flash, and its amber heartbeat is not used that way.
- A solid red LED is a generic control fault on UTEC. On Emerson it is an internal gas valve error, microprocessor or frequency check — pointing at the gas valve rather than at the board.
- Twelve red flashes is an open hot surface igniter on UTEC and an ignitor failure on Emerson — the same repair, worded differently.
How to fix it
- Nothing to fix here. This page exists so a flash count is read against the right table.
- Where the two tables agree, the pages on this site apply to both generations.
- Where they differ, the difference is noted on the page concerned.
Notes
Both tables use the same footnote markers, and those are worth knowing: an asterisk means the code is stored in the error code array and can be recalled later, a single hash means a one hour soft lockout, and a double hash means a hard lockout that will not clear itself.
Related
- Fault code retrieval — How to read and clear stored fault codes on York UTEC boards
- 1 amber flash — Normal operation with a call for heat, Emerson boards
All codes for this manufacturer
York, Luxaire and Coleman furnace flash codes — every code, with what differs between models.
What the fix costs
Nothing to repair on this page — but reading a code against the wrong table has a price tag, and the four diagnosis-changing counts each carry one. Five red on an Emerson board can be a blown on-board fuse, a $5–150 fix per the control board cost guide; read it as the UTEC rollout and you have commissioned a combustion inspection for an electrical fault — and the reverse misreading, dismissing a genuine rollout as a fuse, is the direction that is actually dangerous. A solid red on Emerson points at gas valve internals, a $300–900 part that is never DIY, where the UTEC reading points at the board itself at $400–900 installed. Seven and eight red decide whether the furnace will release itself in an hour or stay locked out — the difference between “wait and observe” and “call now.” Every one of those forks is resolved for free by reading a label, which makes the board part number the highest-yield check in York diagnosis, per the repair cost guide's general rule that knowing the real fault before the quote is the cheapest leverage a homeowner has.
Check the label yourself or ask the technician?
Reading a printed part number is technically trivial, but the label sits inside the furnace cabinet — and on many of these furnaces, removing the blower compartment door opens the door switch and cuts the furnace's power, which is startling if unexpected and means the furnace was just interrupted mid-whatever-it-was-doing. The conservative path costs nothing extra: if you are not already comfortable opening the furnace, have the technician photograph the board label at the next scheduled service and keep the photo with the house papers. From then on, every flash count this furnace ever shows can be read against the correct table from the couch, and this site's York pages will tell you when the two generations disagree. Do not guess from the furnace's age — the generations were sold consecutively and the overlap is real; the label is the answer.
The same trap across the industry
York is not unusual in running two incompatible code tables under one brand name — the site's same code, different meanings page documents ICP, Rheem and Goodman all publishing contradictory lists, with Rheem's two systems as the starkest case: three blinks is an open limit on one Rheem control and a pressure-switch fault on another. What is unusual about York's situation is where its old table went: the White-Rodgers Emerson lineage behind these boards is the same one behind Goodman's controls, which is why the Goodman GMEC96 red-flash table matches the York UTEC red table nearly code for code and the pages of both families cross-reference each other. Two brands, one ancestry, and a shared lesson: the control family, not the brand on the cabinet, decides what a flash count means.
What this looks like
From the outside, this usually shows up as the thermostat screen is blank — that walkthrough covers what to check in order, and when it stops being a homeowner job.