York® Sunline KE Series Packaged Gas/Electric Rooftop Unit – Supplied & Professionally Installed by 4Most Energy
The York® Sunline KE Series is a factory-assembled, single-package gas/electric rooftop unit built for small commercial buildings in the 3 to 6 nominal ton range. It pairs up to 13.4 SEER2 cooling with single-stage gas heat — a direct-spark-ignition furnace rated at 81% AFUE on single-phase models — in one factory-charged cabinet. R-454B refrigerant, micro-channel aluminum condenser coils, and the Smart Equipment™ control board with on-board diagnostics and USB data logging are standard on every KE036 through KE072 model, while an integrated gas controller, post-purge induced-draft combustion, and an aluminized or stainless steel tubular heat exchanger keep combustion safe and efficient. The 6-ton KE072 steps up to a 2-stage scroll compressor with IntelliSpeed variable frequency drive for stronger part-load performance. Full-perimeter base rails, forklift slots, and a shared cabinet footprint across all four sizes simplify rigging, curb selection, and future service.
Rated performance depends entirely on correct field installation. Ontario code requires a licensed TSSA gas technician to size the gas line and meter to the unit's heat input option (50 to 125 MBH), with combustion and gas-train testing at start-up and correct venting clearances per the manufacturer's diagrams. Because R-454B is a mildly flammable A2L refrigerant, proper refrigerant handling and optional leak-detection sensor commissioning by a licensed refrigeration mechanic are equally critical. Roof curb selection (8 in. or 14 in. NRCA-approved curbs), structural load review, and ESA-compliant electrical hookup sized to the unit's MCA/MOCP rating are the code-driven steps that determine whether the rated SEER2 and AFUE actually show up on the utility bill. 4Most Energy handles packaged rooftop gas/electric installation in Toronto, packaged rooftop replacement across the GTA, and York Sunline KE installation projects throughout Ontario — with combustion testing and R-454B commissioning on every job.
Replacement Option
The York® Sunline KE Series shares a common roof curb across every size in the line, and — using an appropriately sized curb adapter to bridge differing roof curb and duct footprints — it can replace aging Trane, Lennox, Daikin, Rheem, and AAON packaged gas/electric units of comparable tonnage. This lets 4Most Energy upgrade a building to a modern, low-GWP refrigerant rooftop solution without necessarily requiring a full roof curb and structural rework, minimizing both project cost and rooftop downtime. Comparing gas heat with heat pump options? See the York Sunline WN Series heat pump rooftop unit.
Warranty
York backs the Sunline KE Series with a 1-year limited warranty on the complete unit, a 5-year limited warranty on the compressor and factory-installed electric heater elements, and a 10-year limited warranty on the aluminized or stainless steel heat exchanger. 4Most Energy handles warranty registration and start-up documentation on your behalf.
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Why Install the York Sunline KE with 4Most Energy?
Gas Heat & Combustion Expertise
Licensed TSSA gas technicians size the gas line, verify supply pressure, and complete combustion and gas-train testing at start-up.
Proper System Sizing
We evaluate cooling load, heating load, gas heat input stage, and gas and electrical capacity before installation.
Professional Rooftop Installation
Complete coordination of curb, rigging, ductwork, electrical, and controls connections.
A2L Refrigerant Expertise
Proper R-454B handling, charging, and optional refrigerant detection system (RDS) commissioning by licensed refrigeration mechanics.
Transparent Installation Planning
Before installation, we review the existing rooftop unit, curb, gas and electrical service, and access requirements, so your quote reflects the real scope of work.
Ongoing Maintenance Support
Service options for combustion testing, gas-train inspection, coils, filters, RDS sensor checks, and Smart Equipment™ control diagnostics.
- R-454B refrigerant with micro-channel coils a lower-GWP alternative to legacy R-410A, paired with micro-channel aluminum condenser coils for improved heat transfer and a reduced refrigerant charge.
- Smart Equipment™ control board embedded LCD display, on-board USB port for data logging and software updates, on-board diagnostics with fault code memory, and compatibility with a standard thermostat, zone sensor, or BACnet MS/TP, Modbus, and N2 building automation protocols.
- Single-stage gas heat induced-draft combustion with post-purge logic, energy-saving direct spark ignition, and a redundant main gas valve; aluminized steel heat exchanger standard, stainless steel available for corrosive environments.
- 2-stage IntelliSpeed compressor (KE072) the 6-ton model uses a 2-stage scroll compressor with IntelliSpeed variable frequency drive for improved part-load efficiency.
- Low-ambient operation to 0°F integrated low-ambient control allows cooling operation down to 0°F outdoor ambient without additional field-installed accessories.
- Anti-short cycle and nuisance-trip protection programmable minimum run times and a “three times, you're out” lockout philosophy on high/low-pressure switches and freezestats reduce false service calls.
- Convertible airflow design factory-covered duct openings convert between bottom and horizontal discharge without additional accessory panels.
- Full-perimeter base rails permanently attached, with forklift access from three sides and rigging holes for overhead crane placement.
- Factory-installed economizer options dry bulb or dual enthalpy economizers with AMCA 511 Class 1A low-leak dampers, capable of introducing up to 100% outdoor air for free cooling.
- Shared cabinet footprint all four sizes (3 to 6 tons) use the same cabinet and roof curb, simplifying future capacity changes or multi-unit sites.
- Optional refrigerant detection system (RDS) factory- or field-installed sensors provide R-454B leak detection and automatically dilute refrigerant gas while alarming the control board.
Sunline KE Specifications
| Model | Nominal Tons | Net Cooling (Btu/hr) | SEER2 | EER2 / IEER | Gas Heat Input (MBH) | Sound (dBA, AHRI 270) | Operating Weight (lb) |
|---|---|---|---|---|---|---|---|
| KE036 | 3.0 | 35,400 | 13.4 | 11.4 EER2 | 50 / 100 | 79 | 470 |
| KE048 | 4.0 | 49,000 | 13.4 | 11.2 EER2 | 75 / 125 | 79 | 598 |
| KE060 | 5.0 | 57,000 | 13.4 | 11.4 EER2 | 100 / 125 | Confirm | 632 |
| KE072 | 6.0 | 69,000 | — | 16.0 IEER / 11.2 EER | 100 / 125 | 83 | 665 |
Net cooling capacity and SEER2/EER2 rated per AHRI Standard 210/240; sound ratings per AHRI Standard 270. The KE072 uses a 2-stage scroll compressor with
IntelliSpeed variable frequency drive. All models share the same 82-1/4 in. L × 44-7/8 in. W × 32-5/8 in. H cabinet footprint and roof curb.
| Base Unit Electrical (Voltage – RLA/LRA · MCA · Max Fuse) | KE036 | KE048 | KE060 |
|---|---|---|---|
| 208-1-60 | 16.7/93.5 · 29.2 A · 40 A | 22.4/126 · 37.9 A · 50 A | 23.7/157 · 40.0 A · 60 A |
| 230-1-60 | 16.7/93.5 · 29.5 A · 40 A | 22.4/126 · 38.2 A · 50 A | 23.7/157 · 40.0 A · 60 A |
| 208-3-60 | 12.2/97.5 · 23.6 A · 30 A | 12.8/120.4 · 25.9 A · 35 A | 16.0/156.4 · 27.1 A · 35 A |
| 230-3-60 | 12.2/97.5 · 23.9 A · 30 A | 12.8/120.4 · 26.2 A · 35 A | 16.0/156.4 · 27.1 A · 35 A |
| 460-3-60 | — | — | 7.1/69.0 · 12.4 A · 15 A |
| 575-3-60 | — | — | 6.4/47.8 · 11.0 A · 15 A |
Electrical data shown for base units without electric heat. The 6-ton KE072 is 3-phase only (208/230-3-60, 460-3-60, or 575-3-60); its electrical
data is confirmed from the manufacturer's tables at quotation. A field-supplied and field-installed disconnect switch is required by code on all sizes.
The Sunline KE is sized first by cooling load (3–6 nominal tons) using a proper commercial load calculation — not by matching the tonnage of the unit being replaced, since older rooftop units on the same curb were frequently oversized. Gas heat input is matched separately to the building's design heating load and Ontario winter design temperature, since each size offers two heat input options (for example, 50 or 100 MBH on the 3-ton KE036). Because all four sizes share the same cabinet and roof curb, a tonnage change within the KE036–KE072 range typically does not require a new curb. Buildings needing higher part-load efficiency should consider the KE072 with its 2-stage IntelliSpeed compressor. 4Most Energy performs load calculation, gas and electrical capacity verification, and curb/structural review as part of every quote before ordering.
Installation & Assessment Checklist
| Phase | Description & Key Requirements | |
|---|---|---|
| Step 1 | Site Assessment | Existing equipment inspection, gas service and meter capacity check, electrical service review, and roof curb, slab, or steel-beam mounting evaluation. |
| Step 2 | Load Calculation & Unit Sizing | Confirm correct tonnage, gas heat input stage, economizer/BAS requirements, and duct configuration (bottom or horizontal). |
| Step 3 | Rigging & Placement | The Sunline KE's full-perimeter base rails, forklift slots, and rigging holes allow forklift or overhead crane placement onto the roof curb, slab, or beams. |
| Step 4 | Roof Curb & Structural Prep | Install or verify the correct 8 in. or 14 in. NRCA-approved roof curb, full-perimeter gasketing, and structural support. |
| Step 5 | Gas Line & Venting Connection | Licensed TSSA gas technician sizes and connects the gas line for the unit's rated heat input, verifies supply pressure, and confirms combustion air and vent hood clearances. |
| Step 6 | Electrical Connection | ESA-compliant hookup to a field-installed disconnect switch, sized to the unit's MCA/MOCP rating for the building's voltage and phase. |
| Step 7 | Ductwork Tie-in | Supply and return duct connection matched to bottom or horizontal discharge, with sealed transitions. |
| Step 8 | Commissioning | Refrigerant charge verification, combustion analysis and gas-train test, Smart Equipment™ configuration (thermostat, zone sensor, or BAS integration), and airflow confirmation, with start-up documentation filed. |
| Step 9 | Final Walkthrough | Filter access, service clearances, and control board operation demonstrated before the crew leaves site. |
York's standard coverage on the Sunline KE Series is a 1-year limited warranty on the complete unit, a 5-year limited warranty on the compressor, and a 10-year limited warranty on the heat exchanger (aluminized steel standard, stainless steel optional). 4Most Energy completes and files the required start-up and combustion test documentation to keep warranty coverage valid.
Routine maintenance is straightforward by design: hinged, tool-less filter, motor, and electrical access panels speed up inspections, and the Smart Equipment™ board's on-board diagnostics and five-fault memory (retained through power loss) let a technician diagnose an issue before opening a single panel. 4Most Energy recommends annual combustion testing and gas-train inspection, condenser and evaporator coil cleaning, filter replacement (1 in. standard, 2 in. pleated MERV 8 optional), and periodic RDS sensor verification on units equipped with refrigerant detection. 4Most Energy offers scheduled maintenance plans covering filter changes, combustion analysis, coil cleaning, and control board diagnostics.
Service Area
Greater Toronto Area (GTA) and surrounding regions
Toronto, Markham, Richmond Hill, Vaughan, Aurora, Newmarket, Scarborough, Brampton, and Mississauga.
Extended Service Area: Stouffville, Oshawa, Barrie, Orangeville, Hamilton, St. Catharines, Guelph, Kitchener.
Frequently Asked Questions
What does the Smart Equipment™ control board add over a standard thermostat-controlled unit?
It provides on-board diagnostics with fault code memory, a USB port for data logging and software updates, factory-installed supply, return, and outdoor air temperature sensors that reduce field wiring, and native compatibility with BACnet MS/TP, Modbus, or N2 building automation — without extra field controllers.
Is R-454B refrigerant safe to use in an occupied building?
Yes. R-454B is a mildly flammable (A2L) refrigerant with a lower GWP than legacy R-410A. It must be installed and serviced by a licensed refrigeration mechanic, which 4Most Energy provides on every job, and an optional refrigerant detection system (RDS) is available for automated leak sensing.
Can I upgrade tonnage later without replacing the roof curb?
In many cases, yes — all four Sunline KE sizes (3 to 6 tons) share the same cabinet footprint and roof curb, so a future capacity change may not require new curb work. 4Most Energy always verifies gas and electrical capacity for the new size before quoting.
Is propane an option?
Yes. A factory propane conversion kit is available with the burner orifices, pilot orifices, and gas valve parts needed to convert from natural gas, and high-altitude kits are available for elevations between 2,000 and 6,000 ft.
Do you need a crane to install the Sunline KE?
It depends on roof height and access. The unit's full-perimeter base rails, three-side forklift slots, and rigging holes allow either forklift or overhead crane placement — we confirm the rigging method during the site assessment and include it in your quote.
What maintenance does the Sunline KE need?
We recommend annual combustion testing and gas-train inspection, condenser and evaporator coil cleaning, filter replacement, and periodic RDS sensor checks on units with refrigerant detection. Tool-less access panels and the Smart Equipment™ fault memory keep service visits quick.
Does the Sunline KE Series qualify for Ontario energy rebates?
Eligibility depends on each program's current SEER2/EER2 thresholds, so 4Most Energy confirms it against the specific program when quoting. Most residential programs do not apply to commercial rooftop equipment.
