Packaged Heat Pump System York XN 4 Ton Three-Phase | Montreal, Laval, Longueuil, South Shore and North Shore
Replacing an R-410A rooftop unit without changing your bearings
Your rooftop unit is reaching the end of its life and the rest of your equipment fleet runs on R-410A. You can replace it with a heat pump from the same refrigerant family: the 4 ton YORK Sunline XN (48,000 BTU/h nominal), powered at 208/230 V three-phase. At AirGreen, an HVAC contractor based in Montreal, we replace rooftop units on businesses and buildings in Laval, in Longueuil, on the North Shore and on the South Shore. Here is what you need to know to carry out a like-for-like replacement.
The packaged concept, seen from a replacement standpoint
A packaged heat pump brings the whole system together in a single outdoor cabinet: scroll compressor, outdoor coil, indoor coil, supply fan, filters and control. Inside the building, all that is left are the ducts that distribute the air. YORK ships every XN unit charged with refrigerant, wired, piped and tested at the factory, which keeps site work to a minimum.
During a replacement, the old unit comes off its roof curb and the new one takes its place, connected to the same duct openings. The YORK guide also provides for installation on a ground-level pad or on steel beams.
R-410A: proven technology, familiar maintenance
R-410A is the previous-generation refrigerant, used for many years in commercial rooftop units. The technicians who already service your equipment know its service procedures: the same habits and the same diagnostic approach from one unit to the next.
The XN048 comes with a factory charge of 13 lb 10 oz of R-410A. Its circuit includes a filter-drier, high and low pressure switches and a freeze protection thermostat on the suction line. Service ports on the suction and liquid lines make it possible to read pressures without losing refrigerant.
Key specifications
- Rated capacity: 4 tons (48,000 BTU/h)
- AHRI net cooling: 47,000 BTU/h
- Heating at 47 °F (8.3 °C): 44,000 BTU/h, COP of 3.2
- Heating at 17 °F (-8.3 °C): 24,900 BTU/h, COP of 2.1
- Efficiency under the previous standard (no SEER2 rating published for the XN series): SEER 14.0, HSPF 8.0 and EER 11.8
- Rated airflow: 1,450 CFM (ft³/min)
- Power supply: 208/230 V, three-phase, 60 Hz
- Dimensions (width x length x height): 44.88 x 82.25 x 32.63 in.
- Operating weight: 616 lb
- Outdoor sound level (AHRI 270 rating): 80 dB(A)
Factory configuration of this model
Model number XN048C00B2C1AAA1A2 describes the equipment as it leaves the factory:
- standard static pressure indoor fan, belt driven
- factory-installed economizer, without barometric relief damper
- no service option, so no built-in disconnect and no convenience outlet
- no optional sensor
- stand-alone Smart Equipment control
- standard coils, without E-Coat coating
- heat pump without factory-installed electric heat (code C00)
The economizer can bring in up to 100% outdoor air when that air is cool enough, which allows cooling in mid-season with the compressor off. The dampers, of the low-leakage type (AMCA 511, class 1A), close completely in the event of a power failure. If excess air has to be relieved while it runs, a barometric relief damper is added as an accessory.
What makes the replacement simpler on the roof
- Common roof curb: all ZE/XN models from 3 to 6 tons share the same cabinet and the same curb. If your current unit belongs to this YORK family, the new one sits on the curb already in place, once its condition has been checked.
- Convertible connections: through the bottom or horizontally through the back, even with the economizer. You only have to remove the corresponding sheet metal panels.
- Service entries: knockouts under the unit and on the side, plus a marked location for mounting a field-supplied disconnect.
- Adjustable airflow: the belt drive includes an adjustable-pitch motor sheave to match the fan speed to your existing ducts.
- Readings without disassembly: ports on the cabinet make it possible to measure indoor fan performance without removing a panel.
Checking the existing electrical circuit
For this configuration, without electric heat, the YORK guide lists a minimum circuit ampacity (MCA) of 24.2 A and a maximum overcurrent protection of 30 A, with a time-delay fuse or an HACR type breaker. The allowable voltage runs from 187 to 252 V. We compare these values with the old unit's circuit before confirming the replacement.
Heating: the heat pump first, electric backup next
In heating mode, the XN048 delivers 44,000 BTU/h at 47 °F (8.3 °C) with a COP of 3.2, then 24,900 BTU/h at 17 °F (-8.3 °C) with a COP of 2.1. As with any heat pump, capacity drops as the outdoor temperature falls. For the Quebec winter, we therefore plan for electric backup heat sized to your building's heat loss.
For this model, the YORK guide lists the E05, E07, E10, E15 and E20 kits. Their capacity depends on the actual voltage: the E10 kit delivers 8 kW at 208 V and 10.6 kW at 230 V. The nickel-chrome elements, protected by thermal limit switches, connect to a single power supply, and the heater section slides out of the unit for maintenance.
Smart Equipment: clearer diagnostics than before
On XN heat pumps, the Smart Equipment control comes standard. Its LCD screen shows unit status, supply air, return air and outdoor air temperatures as well as fault codes. The USB port is used for data logging, fault review, software updates and start-up reports.
The control accepts a conventional thermostat, a zone sensor or a building management system. It includes a short-cycle delay and locks out the compressor only after three trips of a safety within two hours. The last five alarms stay in memory, even after a power outage. Thanks to the built-in low ambient control, the unit cools down to 0 °F (-17.8 °C) outdoors, without any accessory.
Installation tips for a successful replacement
- Survey of the existing unit: capacity, power supply, curb dimensions and position of the duct openings.
- Lifting: the perimeter base rails have lifting holes at the four corners for the crane and forklift openings on three sides.
- Clearances with the economizer: 24 in. at the front, 36 in. at the rear, 36 in. on the left side for filter access, 24 in. on the right side and 72 in. above the unit.
- Condensate: 3/4 in. female PVC connection, to be protected from freezing depending on the drain routing.
- Filters: three 1 in. disposable filters on delivery, in a rack that also accepts 2 in. filters.
Why entrust this replacement to AirGreen
A rooftop unit replacement comes down to the details: curb, power supply, lifting, ducts and airflow adjustment. Our crews handle all of it from start to finish.
- Free on-site estimate: we go up on the roof, we survey the existing unit and we check the curb, the ducts and the electrical circuit.
- Sizing: we confirm that 4 tons suits your cooling and heating loads, then we select the appropriate electric backup kit.
- Installation by our own crews: removal of the old unit, lifting, connections, commissioning and programming of the Smart Equipment control.
- Maintenance: filters, coils, belt and a check of the safeties, on a schedule suited to your building.
We serve Montreal, Laval, Longueuil, the North Shore and the South Shore. To replace your R-410A rooftop unit with a 4 ton YORK XN packaged heat pump, call 514 316-2973 or use the form on airgreen.ca. We will book your free on-site estimate quickly.