Carrier Infinity Greenspeed Service in Burbank
Fast take: Burbank Carrier HVAC diagnoses and repairs Carrier Greenspeed variable-speed AC and heat pumps - 24VNA6, 26VNA1, 25VNA4 - across Burbank, CA, including hillside rebuilds in Burbank Hills (91504). Inverter and board work runs $400-$2,000; call (213) 277-7557 or book online for communication-fault, inverter, and modulation issues.
By the numbers
- Greenspeed lines we service: 26VNA1 (Infinity 21), 24VNA6 (Infinity 26), 27VNA3/25VNA4 heat pumps.
- Greenspeed modulates the inverter compressor roughly 25-100 percent of capacity.
- Requires the Infinity System Control (SYSTXCCITC01) over the ABCD communicating bus.
- Common faults: 178 indoor comm, 179 outdoor comm, plus inverter and sensor alerts.
- Inverter/control board: $400-$2,000; Greenspeed compressor: $1,200-$3,500 out of warranty.
- Service area 91501-91523; hours Mon-Sat 7am-7pm; emergency calls anytime.
How does Greenspeed actually work?
Greenspeed Intelligence pairs a variable-speed inverter compressor with the Infinity System Control. Instead of slamming on at full power and off again like a single-stage unit, it ramps the compressor up and down to match the real cooling load - down to about 25 percent on a mild morning, up to 100 percent on a 95 F Burbank afternoon. Those long, low-speed runs hold temperature within a degree, wring out humidity, and run quietly. The catch: every bit of that depends on the communicating control and clean ABCD wiring.
| Symptom / code | Likely cause | Cost lane |
|---|---|---|
| Runs single-speed only | Lost comm; control or ABCD wiring | $200-$2,000 |
| Code 178 (indoor comm) | Thermostat-to-indoor-board link | $200-$1,200 |
| Code 179 (outdoor comm) | Control-to-condenser wiring/board | $300-$2,000 |
| Inverter/outdoor alert, no start | Inverter PCB or compressor | $400-$3,500 |
| Weak cooling, code 44 | Airflow restriction (filter/duct) | $150-$3,000 |
Which Greenspeed models do you service, and where do they fit?
Greenspeed spans flagship AC and heat pumps across two naming generations, both common in Burbank homes:
- 24VNA6 (Infinity 26) AC: the high-SEER flagship air conditioner, up to ~26 SEER on the larger sizes - a fit for a big two-story rebuild with serious cooling load.
- 26VNA1 (Infinity 21) AC: the current-naming variable-speed AC; strong efficiency without the absolute top-tier price.
- 27VNA3 (Infinity 23) heat pump: Carrier's most efficient heat pump, ideal for a gas-to-electric conversion in mild Climate Zone 9.
- 25VNA4 (Infinity 24) heat pump: recent flagship, up to ~22 SEER2 and ~10.5 HSPF2.
- 27VNA1 (Infinity 21 Ultimate Cold Climate): cold-climate Greenspeed - overkill for Burbank winters, but documented here for completeness.
Every one of these requires the Infinity System Control (SYSTXCCITC01) over the four-wire ABCD bus to modulate; without it they default to single-stage.
What faults are specific to Greenspeed systems?
Greenspeed adds an inverter and a communicating bus, so its fault set goes beyond the simple capacitor-and-contactor pattern of a value unit:
| Code / symptom | What it means | Component |
|---|---|---|
| 178 | Indoor unit communication fault | Thermostat-to-indoor-board link, ABCD wiring, indoor board |
| 179 | Outdoor unit communication fault | Control-to-condenser ABCD wiring, outdoor board, line voltage |
| 73 | Voltage at run cap, no compressor call | Contactor, relay, run-cap wiring (24ANA/25HNA families) |
| 44 | Excessive air-delivery restriction | Filter, duct, ECM blower |
| 54 / 56 | Suction / OAT-OCT thermistor error | Temperature sensors |
| Runs single-speed only | Lost communication; not modulating | Infinity control, ABCD bus, inverter PCB |
The touchscreen reports both the number and a plain-language line, so we read the fault history before opening a panel and target the actual component instead of guessing.
Is Greenspeed the right fit for a Burbank rebuild?
This is the install decision that matters most. Greenspeed earns its premium in larger or two-story homes - the hillside rebuilds above Burbank Hills, big-footage Toluca Lake-adjacent properties - where long, low-speed runs hold temperature within a degree and wring out humidity. In a tight 1,000-square-foot Magnolia Park cottage, a right-sized Performance two-stage often delivers similar comfort for less, and the Greenspeed range never gets used. The install also assumes the ductwork can carry the rated airflow at the right static pressure; on a leaky pre-war duct system, the efficiency on the label never reaches the room. We size to a Manual J load, check the ducts, then match the tier to the home.
Why do communication faults happen here?
The ABCD bus is four small wires, and they are vulnerable to the same things that age any Burbank install: rodents in an old attic, water intrusion at the outdoor connection, a loose terminal from thermal cycling, or a board that took a power surge. Because the Infinity touchscreen reports both the numeric code and a plain-language description, we start there, then ohm out the bus and check line voltage at the condenser before we ever quote a board. Replacing a $1,200 control to fix a corroded $3 terminal helps no one.
What if my Greenspeed system is still under warranty?
Greenspeed equipment is premium, and Carrier's parts warranty - typically 10 years with registration - covers the inverter compressor, the priciest component. If your system is in that window, route a sealed-system or compressor claim through Carrier's authorized dealer first so you keep the coverage. We handle the out-of-warranty side: comm-wiring repairs, board diagnostics, sensor faults, and second opinions when a quote feels inflated.
One honest cost note worth flagging: because the inverter and the communicating board are where Greenspeed most often faults, many "compressor" scares turn out to be a board or a corroded ABCD terminal at a fraction of the price. Verifying the warranty status and isolating the true failure before anyone orders a compressor is how you avoid spending $1,200 to $3,500 on a part that was never broken.
Common questions
My Infinity Greenspeed system runs but only at one speed - why?
Variable-speed modulation needs the Infinity System Control communicating with the outdoor inverter over the ABCD bus. If that link drops, the system defaults to single-stage to keep cooling. Causes are loose or corroded comm wiring, a failed communicating board, or a control swapped for a non-Infinity thermostat. The touchscreen usually logs a 178 or 179 to confirm it.
What does fault code 178 or 179 mean on my Carrier Infinity?
178 is an indoor communication fault - the thermostat cannot talk to the indoor board - and 179 is an outdoor communication fault between the control and the condenser. Both point to the four-wire ABCD bus: damaged or loose wiring, a water-damaged board, or lost line voltage to the outdoor unit. We trace the bus end to end before condemning a board.
Is the Greenspeed inverter compressor worth repairing?
Often the compressor itself is fine and the fault is the inverter or control board, which is a fraction of compressor cost. A true Greenspeed compressor replacement runs $1,200-$3,500 out of warranty, so on an older unit we run the repair-or-replace math. If Carrier still covers the part, you pay labor only - another reason to verify warranty first.
Is an Infinity Greenspeed overkill for a Burbank bungalow?
Sometimes. Greenspeed shines in larger or two-story homes that benefit from long, low-speed runs and tight humidity control. In a small 1,000-square-foot Magnolia Park cottage, a right-sized Performance two-stage may deliver similar comfort for less. We size to the load, then match the tier to the home - not the other way around.
Related: Infinity System Control setup, Performance series (the mid-tier alternative), and sizing guidance.