On York/Johnson Controls J**ZJ rooftops, the Simplicity SE (Smart Equipment) unit control board does not have a numbered flash-code chart like the older Simplicity board on Predator units. It shows active alarms on its LCD and uses a red FAULT LED: a 1/2-second on/off flash means one or more alarms are active, and a 1/10-second flash means a networking or firmware error, per York form 5167530-JIM-H-0218 (J**ZJ, 6-1/2 to 12-1/2 ton). The numbered flash codes on these units come from the separate gas ignition control board.
Is "SSE" the same as Simplicity SE and Smart Equipment?
Yes. York form 1183875-YIM-A-1014 (ZJ150) titles its control section "Simplicity SE (Smart Equipment)" and describes the LCD as a standard item on the Simplicity SE control in commercial packaged and split systems. The J**ZJ manual calls the same board the "Smart Equipment UCB." Our replacement listing for J07ZJ and J10ZJ models is titled "SSE Control Board."
It is a different board from the Simplicity Lite control board listed for many J03ZF units on our site. Our advice: don't read an SE board with a Simplicity Lite flash-code chart.
What do the LEDs on the Simplicity SE board mean?
| LED / output | What form 5167530-JIM-H-0218 says |
|---|---|
| POWER (green) | Lit indicates 24 VAC is present at the C and 24V terminals |
| FAULT (red) | Hard lockout, networking error and firmware error indicator. 1/2 second on/off flashing = one or more alarms currently active. 1/10th second on/off flashing = networking error (polarity, addressing, etc.) or firmware error |
| SA BUS (green) | Lit or flickering indicates SA bus communication is active |
| X terminal | Hard lockout indicator, 24 volt output to light a thermostat LED |
After power-up, the LCD runs a start-up countdown. The manual says that when the controller is ready, the screen is blank if no faults are present. You navigate with the joystick and the ENTER and CANCEL buttons below the LCD. Pressing CANCEL repeatedly returns you to the first "Status, Alarms" screen.
Which cooling faults lock out a compressor?
The J**ZJ manual lists these cooling operation errors. Each refrigerant system is handled on its own: "On any fault, only the associated system will be affected." All system errors override compressor minimum run times.
| Input | Trip point | What the board does | Lockout |
|---|---|---|---|
| High-pressure limit switch | Opens at 625 ± 25 psig | De-energizes the compressor, starts the anti-short cycle delay (ASCD), restarts after the ASCD if cooling is still called | 3 openings within 2 hours |
| Low-pressure limit switch | Opens at 50 ± 5 psig. Ignored for the first 30 seconds, must close in the next 30 seconds | Same response; after it is proven, an opening longer than 5 seconds counts | 3 openings within 1 hour |
| Evaporator low limit sensor (EC1, EC2) | Below 26°F (default) at the suction line | Same response | 3 occurrences within 2 hours |
When a compressor locks out and the other compressor is not running, the condenser fans are de-energized too. Low ambient cooling is not a fault: below 45°F outdoor (default) with a cooling call, the board cycles compressors 10 minutes on and 5 minutes off, with the indoor blower running throughout the cycle.
Which other alarms can the SE board raise?
| Input | Alarm condition (5167530-JIM-H-0218, Table 30) |
|---|---|
| DFS (dirty filter switch, optional) | Switch closed for more than 15 seconds during blower operation starts a notification alarm |
| APS (air proving switch, optional) | Must close within 30 seconds of blower start and not open for more than 10 seconds while running, or an "APS open" alarm occurs. Must open within 30 seconds of blower stop, or an "APS stuck closed" alarm occurs |
| VFDFLT | 24 VAC from the normally open VFD alarm contact shuts the unit down and causes a "VFD fault" alarm |
| RAT, OAT, SAT, EC1 | Listed as inputs required for operation (OAT may be a communicated value) |
For the sensor side of these alarms, including the 3.625 VDC open-circuit reading the manual gives, see our sensor article linked below.
What about flash codes during gas heat?
On gas-heat J**ZJ units, the ignition control board has its own LED. Form 5167530-JIM-H-0218 has a separate table for it, Table 32 "Ignition Control Flash Codes" (page 70). Its fault conditions include pressure switch stuck closed, pressure switch failed to close, limit switch open, flame present with gas off, gas valve energized out of sequence, ignition lockout, and no power or control failure.
The web copy of that table we read does not line up the flash counts with the faults cleanly, so we do not pair them here. Read the flash count against the ignition control label in your unit's control box or the printed manual.
Parts involved
| Component | Role | Where to find it |
|---|---|---|
| Simplicity SE unit control board | The board described above. Listed for some J07ZJ and J10ZJ models. | York S1-6421651 SSE Control Board, 2-Stage, Non-Communicating | OEM Source 1 Part |
| SSE economizer add-on board | Economizer board for SSE-controlled units. Listed for ZQG06 models. | York S1-6434434 Circuit Board, SSE, Economizer Add on, V5.0 | OEM Source 1 Part |
| High-pressure control | Listed for J07ZJ and J10ZJ. Its title rating (625 open) is in line with the manual's 625 ± 25 psig trip; confirm by part number. | York S1-5992116 Refrigerant Pressure Control, 625 Open / 525 Close Flare, PSIG | OEM Source 1 Part |
| Air temperature sensor | RAT, SAT and OAT are required inputs. Listed for J07ZJ and J10ZJ. | York S1-6043480 Temperature Sensor, Outside/Return/Supply, Air, 6 in | OEM Source 1 Part |
| Air temperature sensor | Listed for J10ZJ, J15ZJ and other J-code series. | York S1-33103655000 Temperature Sensor, Return, Supply, Outdoor | OEM Source 1 Part |
Which York units this applies to
- York J10ZJ parts — 10-ton J**ZJ rooftop, the primary unit covered by form 5167530-JIM-H-0218.
- York J07ZJ parts — 7.5-ton J**ZJ, same manual.
- York J15ZJ parts — 15-ton ZJ; uses its own manual.
- York ZF180 parts — 15-ton ZF; uses its own manual, so check its control type there.
- York ZQG06 parts — 5-ton gas/electric; the SSE economizer add-on board is listed here.
Related reading: York S1 (Source 1) part number meaning.
Scope: LED meanings, cooling errors and alarm inputs are from York/Johnson Controls form 5167530-JIM-H-0218 (J**ZJ Series with Smart Equipment, J06 to J12ZJ, 6-1/2 to 12-1/2 ton, 60 Hz, R-410A). The Simplicity SE name is from form 1183875-YIM-A-1014 (ZJ150). Other models, firmware versions and manual revisions can differ. This article does not list LCD alarm text strings beyond those quoted.
Before you order
A control board is rarely the first fix. Check the alarm on the LCD, the switch or sensor behind it and the 24 VAC supply first. If the board is bad, give us the nameplate model and serial number and the part number on the old board, because our SSE board listing is titled as a 2-stage, non-communicating board and may not match every unit. Contact us at help@totalhvacparts.com or 610-487-7999.
Frequently Asked Questions
What does a fast-flashing red FAULT LED mean on a York Simplicity SE board?
Per form 5167530-JIM-H-0218, a 1/10-second on/off flash indicates a networking error (polarity, addressing, etc.) or a firmware error. A slower 1/2-second flash means one or more alarms are active.
How many high-pressure trips lock out a compressor on a York J**ZJ?
Three openings of the high-pressure switch within two hours lock out that compressor. The switch opens at 625 ± 25 psig.
What temperature trips the evaporator low limit on a York ZJ with Smart Equipment?
The EC1/EC2 suction line sensor trips below 26°F by default. Three occurrences within two hours lock out that compressor.
Does the Simplicity SE board show numbered flash codes?
The SE unit control board reports alarms on its LCD and uses its FAULT LED for alarm, network and firmware status. Flash codes during gas heat come from the separate ignition control board, which has its own table in form 5167530-JIM-H-0218.
Sources
- Johnson Controls/York form 5167530-JIM-H-0218, Installation Manual, J**ZJ Series with Smart Equipment, 6-1/2 to 12-1/2 ton, 60 Hz (general p.2, cooling operation errors p.54, control board navigation pp.61–63, Table 30 Smart Equipment UCB Details pp.64–66, Table 32 Ignition Control Flash Codes p.70)
- York form 1183875-YIM-A-1014, Installation Manual, ZJ150 (Simplicity SE (Smart Equipment) control board section)
- York form 127408-YIM-B-0606, Installation Manual, Predator DM090, DM120, DM150, 50 Hz (Table 52 Unit Control Board Flash Codes, for comparison with the older Simplicity board)
- Live product titles for the parts listed above, as shown on each product page
Rooftop units involve line voltage, gas, refrigerant under pressure and rotating parts. Service should be performed only by qualified personnel, following the manual for your unit and your facility's lockout/tagout procedures.