Packaged Heat Pump System York WN 4 Ton 575V | Montreal, Laval, Longueuil, South Shore and North Shore
Mezzanine offices cooled and heated from the warehouse roof
In many warehouses and plants, the offices sit on a mezzanine above shipping or the shop floor. These enclosed rooms need their own system: warehouse air, often hot in summer and cold in winter, is not suited to office work. This 4-ton YORK WN packaged heat pump, fed directly at 575 V three-phase, is installed on the roof above the mezzanine or at grade, and serves these offices through a dedicated duct system. AirGreen plans the lift, the connections and the commissioning in industrial buildings in Montreal, Laval, Longueuil, the North Shore and the South Shore.
Why a packaged unit suits mezzanine offices
A packaged heat pump holds the entire system in a single outdoor cabinet: scroll compressor, outdoor coil, indoor coil, condenser fan and supply blower. Nothing is installed in the mezzanine itself, which preserves the clear height and the work space. The unit connects to the supply and return ducts of the offices; it cools in summer, heats in winter with the heat pump, and a field-installed electric heat kit tops up the heat output in deep cold. Everything runs on electricity, at the voltage already distributed in the building.
Full-length base rails: a predictable lift
The unit is assembled on permanently fastened full-length base rails, which form a rigid footing and protect it during transport. At grade, a forklift can pick it up from three sides; to raise it onto the roof, the lifting holes at the four corners allow a crane lift. The unit can sit on a roof curb, on steel beams above a finished roof or on a pad at grade.
The operating weight of the base unit is 616 lb (621 lb shipping). YORK lists 50 lb more in operation for the economizer and up to 28 lb for an electric heat kit. For the engineer checking the structure, the technical guide also publishes the load distribution:
| Support point (YORK diagram) | A | B | C | D |
|---|---|---|---|---|
| Load on 4-point support (lb) | 135 | 117 | 169 | 195 |
The centre of gravity sits at 38.2 in. (X) and 18.4 in. (Y) against the marks on the YORK diagram, a useful figure for setting the slings before the lift.
From below or from the back: the connections
- Ducts: every model, including those with an economizer, connects from below (by removing the base panels) or horizontally, at the back. The bottom connection passes through the roof curb; the horizontal connection suits a unit set at grade, beside the wall.
- Electrical: the supply wiring enters through a 2 in. knockout, on the side or from below, at a single factory-provided location, which limits roof penetrations. The control wiring has its own separate 7/8 in. openings.
- Air relief: with bottom ducts, the barometric relief damper offered as an accessory mounts on the return panel opening; with horizontal ducts, it mounts on the return duct. Powered exhaust, for its part, is only possible with a bottom connection.
- Condensate: the drain fitting is a 3/4 in. female PVC fitting; an optional bottom drain connection routes it inside the roof curb to reduce the risk of freezing in winter.
- Clearances: 72 in. clear above the unit for the condenser air discharge, 24 in. on the outdoor coil side, plus the filter and economizer access clearances given by YORK.
Specifications of the WN048C00B5CAACA1A1 model
- Rated capacity: 4 tons (48,000 BTU/h)
- Net AHRI cooling: 47,000 BTU/h, EER2 of 11.2
- Heating at 47 °F (8.3 °C): 44,000 BTU/h, COP of 3.0
- Heating at 17 °F (-8.3 °C): 26,000 BTU/h, COP of 2.05
- Seasonal ratings: 13.4 SEER2 and 6.7 HSPF2 (or 14.0 SEER and 8.0 HSPF under the former rating system)
- Rated airflow: 1,450 CFM
- Power supply: 575 V three-phase, 60 Hz (applied voltage from 540 to 630 V)
- Dimensions (width x length x height): 44.88 x 82.25 x 32.63 in.
- Refrigerant: R-454B, an A2L with a low global warming potential
575 V: what your electrician plans for
According to the YORK electrical tables, this model calls for a minimum circuit ampacity (MCA) of 10.3 A and a fuse of no more than 15 A without electric heat. At 575 V, the backup heat kits offered for this size are the E10, E15 and E20; with the E20 kit, which works in two stages, the MCA reaches 35.8 A and the maximum fuse 40 A. The disconnect, supplied on site, mounts at the location provided on the cabinet.
A complete factory configuration
At 575 V, we offer this size in a single factory configuration, the WN048C00B5CAACA1A1, already well equipped: economizer without a barometric relief damper, Smart Equipment control with a BACnet MS/TP, Modbus or N2 communication card, RDS refrigerant detector, belt-drive supply blower (standard static pressure), standard coils and 1 in. disposable filters. When the outdoor air is cool enough, the economizer can bring in up to 100% outdoor air and cool the offices without the compressor. During the estimate, we confirm with you that this package meets your needs.
On site, the LCD screen of the Smart Equipment control shows the supply, return and outdoor air temperatures as well as the fault codes, and our technicians pull the alarm history through the USB port. The built-in low-ambient control also allows cooling down to 0 °F (-17.8 °C) outdoors, handy for offices next to equipment that gives off heat.
The steps of a crane-lift project
- Site visit, survey of the location and verification of the structure with your engineer if needed.
- Preparation of the 8 in. or 14 in. YORK roof curb, with its gasket and nailing strip, or of the steel beams.
- Crane lift using the lifting holes in the rails, then setting the unit on the curb.
- Connection of the ducts, the 575 V supply, the control wiring and the condensate drain.
- Commissioning: setting the airflow with the adjustable-pitch pulley, setting the economizer and the fan delays, and testing the electric heat kit.
AirGreen coordinates the lift, the connections and the commissioning
First step: a free on-site estimate, during which we assess crane access, the structure, the 575 V electrical distribution and the loads of your offices. Our teams then carry out the complete installation and handle the maintenance of the unit season after season.
For mezzanine offices in Montreal, Laval, Longueuil, on the North Shore or on the South Shore, AirGreen inc. is with you from the survey through to maintenance. Call 514 316-2973 or use the form on airgreen.ca: a detailed quote follows quickly.