York Sunline ZE Series Packaged Gas/Electric Rooftop Unit – Supplied & Professionally Installed by 4Most Energy
The York Sunline ZE Series single-package rooftop unit pairs up to 14.0 SEER cooling with single- or two-stage, direct-spark-ignition gas heat rated at 81% AFUE on single-phase models, in a factory-charged, fully assembled cabinet built for 3 to 6 nominal tons of Ontario commercial service. R-410A refrigerant, micro-channel aluminum condenser coils, and the Smart Equipment control board with on-board diagnostics and USB data logging are standard across every ZE036 through ZE072 model, while an integrated gas controller, post-purge induced draft combustion, and a stainless steel or aluminized steel tubular heat exchanger keep combustion safe and efficient. Full-perimeter base rails, forklift slots, and a shared cabinet footprint across all four sizes simplify rigging, curb selection, and future service on every job.
None of this performance is realized without correct field installation. Ontario code requires licensed TSSA gas technician sizing of the gas line and meter to the unit’s specific heat input option (50 to 125 MBH, single- or two-stage), combustion and gas-train testing at start-up, and correct venting clearance per the manufacturer’s diagrams. 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 SEER and AFUE actually show up on the utility bill. 4Most Energy is a certified installer for packaged rooftop gas/electric installation Toronto, packaged rooftop replacement GTA, and York Sunline ZE installation Ontario projects, providing licensed gas technician near me-level combustion testing on every job — and for buildings targeting rebate-eligible efficiency tiers, 4Most Energy also supplies ENERGY STAR packaged rooftop units Toronto owners can pair with available incentive programs.
Replacement Option
The York Sunline ZE Series shares a common roof curb across every size in the line, making it straightforward for 4Most Energy to replace aging Trane, Lennox, Daikin, Rheem, and AAON packaged gas/electric units of comparable tonnage using an appropriately sized curb adapter to bridge differing roof curb and duct footprints. This lets 4Most Energy convert a building from a legacy packaged unit from any of these manufacturers to a reliable R-410A rooftop solution without necessarily requiring a full roof curb and structural rework, minimizing both project cost and installation downtime.
Warranty
York backs the Sunline ZE 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 files start-up documentation to keep coverage valid.
Why Install the York Sunline ZE Series with 4Most Energy?
- R-410A refrigerant — a proven, widely serviced refrigerant paired with micro-channel aluminum condenser coils for improved heat transfer and 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- or two-stage gas heat — induced draft combustion with post-purge logic, energy-saving direct spark ignition, and a redundant main gas valve; two-stage models deliver 60% capacity on first stage and 40% on second stage for smoother comfort control.
- Low ambient operation — the 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 tonnage sizes (3 through 6 ton) use the same cabinet and roof curb, simplifying future capacity changes or multi-unit sites.
- ZE072 IntelliSpeed variable frequency drive — a 2-stage scroll compressor delivering 67% and 100% capacity steps for improved part-load efficiency (14.2 IEER).
ZE Model Specifications
| Model | Nominal Tons | Net Cooling (Btu/hr) |
SEER | EER / IEER | Gas Heat Input (MBH) |
Sound (dBA) |
Operating Weight (lb) |
|---|---|---|---|---|---|---|---|
| ZE036 | 3.0 | 35,500 | 14.0 | 12.0 EER | 50 / 100 / 75 / 115 | 81 | 470 |
| ZE048 | 4.0 | 47,500 | 14.0 | 12.0 EER | 75 / 125 | 80 | 598 |
| ZE060 | 5.0 | 57,000 | 14.0 | 11.8 EER | 75 / 125 | 82 | 632 |
| ZE072 | 6.0 | 66,000 | — | 14.2 IEER / 11.2 EER | 75 / 125 | 83 | 665 |
Net cooling capacity and SEER/EER rated per AHRI Standard 210/240. Sound ratings per AHRI Standard 270. Each tonnage size offers both single-stage (H/J/K/L nomenclature) and two-stage (N/S/P/Q nomenclature) gas heat options — the heat input ranges above reflect both stage configurations available per size. The ZE072 uses a 2-stage scroll compressor with IntelliSpeed variable frequency drive rather than the single-stage scroll compressor used on ZE036–ZE060. All models share the same 82-1/4 in. L x 44-7/8 in. W x 32-5/8 in. H cabinet footprint and roof curb.
Base Unit Electrical Data (No Electric Heat, Belt Drive, Without Powered Convenience Outlet)
| Model | Voltage | Compressor RLA / LRA |
MCA (Amps) |
Max Fuse/Breaker (Amps) |
|---|---|---|---|---|
| ZE036 | 208-1-60 | 15.4 / 83.9 | 28.3 | 35 |
| ZE036 | 230-1-60 | 15.4 / 83.9 | 28.3 | 35 |
| ZE036 | 208-3-60 | 10.4 / 73 | 19.6 | 25 |
| ZE036 | 230-3-60 | 10.4 / 73 | 19.6 | 25 |
| ZE036 | 460-3-60 | 5.8 / 38 | 10.6 | 15 |
| ZE036 | 575-3-60 | 4.2 / 36.5 | 8.2 | 15 |
| ZE048 | 208-1-60 | 19.6 / 130 | 33.5 | 45 |
| ZE048 | 230-1-60 | 19.6 / 130 | 33.5 | 45 |
| ZE048 | 208-3-60 | 13.7 / 83.1 | 23.7 | 30 |
| ZE048 | 230-3-60 | 13.7 / 83.1 | 23.7 | 30 |
| ZE048 | 460-3-60 | 6.2 / 41 | 11.1 | 15 |
| ZE048 | 575-3-60 | 4.8 / 33 | 8.9 | 15 |
| ZE060 | 208-1-60 | 24.4 / 144.2 | 41.6 | 50 |
| ZE060 | 230-1-60 | 24.4 / 144.2 | 41.6 | 50 |
| ZE060 | 208-3-60 | 16 / 110 | 28.7 | 35 |
| ZE060 | 230-3-60 | 16 / 110 | 28.7 | 35 |
| ZE060 | 460-3-60 | 7.8 / 52 | 14.1 | 20 |
| ZE060 | 575-3-60 | 5.7 / 38.9 | 10.8 | 15 |
| ZE072 | 208-3-60 | 19.6 / 136 | 33.2 | 45 |
| ZE072 | 230-3-60 | 19.6 / 136 | 33.2 | 45 |
| ZE072 | 460-3-60 | 9.4 / 66.1 | 16.3 | 25 |
| ZE072 | 575-3-60 | 7.1 / 55.3 | 12.6 | 15 |
Electric heat accessories (5 to 30 kW) substantially increase MCA and max fuse/breaker sizing — confirm exact figures for the selected kW and stage configuration before finalizing an electrical design. A field-supplied and field-installed electrical disconnect switch is required per code on all sizes.
The Sunline ZE line is sized first by cooling load using a proper commercial load calculation for the space served — not by matching the tonnage of the equipment being replaced, since older systems on the same footprint were frequently oversized.
Gas heat input and stage count should be matched separately to the building’s design heating load and Ontario winter design temperature: two-stage gas heat (60%/40% capacity split) generally provides smoother comfort control than single-stage in buildings with variable occupancy or partial loads, at a modest cost premium.
Because all four sizes share the same cabinet and roof curb, a tonnage upgrade or downgrade within the ZE036–ZE072 range typically does not require a new curb — a meaningful advantage when planning for future load changes. Buildings needing higher part-load efficiency should consider the ZE072, which uses a 2-stage scroll compressor with IntelliSpeed variable frequency drive rather than the single-stage compressors on the smaller sizes. 4Most Energy performs load calculation, gas and electrical capacity verification, and curb/structural review as part of every quote before ordering.
Installation & Commissioning Process
| Step | Phase | Scope & 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 and stage count, economizer/BAS requirements, and duct configuration (bottom or horizontal). |
| Step 3 | Rigging & Placement | The Sunline ZE’s full-perimeter base rails, forklift slots, and rigging holes allow fork-lift or overhead crane placement onto the roof curb, slab, or beams. |
| Step 4 | Roof Curb 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 available voltage and phase. |
| Step 7 | Ductwork Tie-in | Supply and return duct connection matched to the unit’s bottom or horizontal configuration, with sealed transitions. |
| Step 8 | Commissioning | Refrigerant charge verification, combustion analysis and gas-train test, Smart Equipment™ control board 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 ZE 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 benefits from the unit’s service-focused design: hinged, tool-less filter, motor, and electrical access panels speed up inspections, and the Smart EquipmentTM control 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, and filter replacement (1 in. standard, 2 in. pleated MERV 8 optional).
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
Should I choose single-stage or two-stage gas heat?
Two-stage gas heat (60% capacity on first stage, 40% on second) generally provides smoother temperature control and reduced cycling in buildings with variable occupancy or partial heating loads, while single-stage is a simpler, lower-cost option well suited to spaces with more consistent heating demand. 4Most Energy can help determine which fits your building during the site assessment.
What does the Smart EquipmentTM 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/outdoor air temperature sensors that reduce field wiring, and native compatibility with BACnet MS/TP, Modbus, or N2 building automation protocols — all without extra field controllers.
Can I upgrade tonnage later without replacing the roof curb?
In many cases yes — all four Sunline ZE sizes (3 through 6 ton) share the same cabinet footprint and roof curb, so a future capacity change may not require new curb work, though 4Most Energy always verifies gas and electrical capacity for the new size before quoting.
Is propane an option?
Yes — the Sunline ZE Series is available with a factory propane conversion kit that includes the necessary burner orifices, pilot orifices, and gas valve parts to convert from natural gas, with high-altitude kits available for elevations between 2,000 and 6,000 ft.
Does the Sunline ZE Series qualify for Ontario energy rebates?
current Ontario/GTA commercial utility rebate program eligibility for R-410A packaged gas/electric equipment should be confirmed against the specific program’s SEER/EER thresholds before quoting, since most residential programs such as the Canada Greener Homes Grant do not apply to commercial rooftop equipment.
