How to Find the Model Number on a PTAC in Your Building

Published October 20, 2026 by New York PTACs, powered by Air Distributors Company, Inc.

Request a Quote

Ask any distributor what speeds up a PTAC quote and you get the same answer: the model number. In a New York building, where one tower can hold four or five unit types across its lines, a model number per line turns a week of back-and-forth into one reply.

Here is where supers and maintenance staff find the number, what to do when the label is gone, and what to photograph before you send a quote request.

Before the cover comes off

Kill the power first. On a plug-in unit, switch off at the controls and unplug. On a hardwired unit, which you find on most 265V systems in hotels and high-rises, turn off the breaker. If the unit has a hot water coil, leave the piping alone. You only need the cover off, not the chassis out.

Bring a flashlight, a rag for the grime, and a phone camera.

The four places a nameplate hides

  1. Side of the chassis. With the room cover off, check both side panels and the area around the control box. Most current units put the plate here.
  2. Back of the front cover. Older units sometimes carry a second label inside the cover.
  3. Chassis base. Some legacy units, including many McQuay and Singer models in postwar towers, put the plate where you only see it after sliding the chassis forward a few inches.
  4. Behind a control door. A few designs tuck the label behind the small hinged panel over the controls.

Ignore the energy label, the wiring diagram, and the last service company's sticker. The nameplate is the one with model number, serial number, voltage, amps, and refrigerant.

Reading the plate

Take one photo of the whole plate and one close-up of the model line. Then note what each field means for the replacement:

  • Model number. The code for brand, series, size, and heat type. On older GE Zoneline units, a letter after the series shows heat type, E for electric or H for heat pump, and two digits give the cooling class. An AZ45E12 is an AZ45 electric heat unit in the 12,000 BTU class.
  • Serial number. Usually encodes the build year. It tells you how old the rest of the line is.
  • Voltage. 208/230V or 265V. The replacement must match. High-rises in the city often run 265V.
  • Amps and heater kW. The circuit size and the electric heat the unit was set up for. A hydronic unit shows little or no heater kW.
  • Refrigerant. R-22 on older units, R-410A or newer on recent ones. It matters for repair decisions, not the replacement order.

When the cover says one brand and the plate says another

Trust the plate. McQuay sold units as McQuay, Singer, Remington, and Climate Control before it left the PTAC business in 2014, and replacement covers from other brands are common in older buildings. Send both names if they differ.

No plate, faded plate, painted-over plate

Steam heat, cigarette smoke, and decades of repainting take labels off. Try these in order:

  1. Check the next apartment on the same line. Stacks usually share a model.
  2. Ask the managing agent. Capital project files, past invoices, and work orders often list the model.
  3. Photograph the unit. Front cover, controls, the chassis with the cover off, the louver, and any pipes. A distributor who handles legacy units often knows the series by its shape.
  4. Measure the sleeve. Inside width, height, and depth narrow it fast. The replacement guide shows how.

A missing plate slows the quote. It does not stop it. Legacy replacements match on sleeve size and heat source as much as model number.

Photos worth taking

  • Full nameplate, plus a close-up of the model and serial numbers
  • The unit with the cover off
  • The receptacle or the hardwired connection
  • Pipes and valves, if the unit has a hot water coil
  • The outdoor louver
  • The empty sleeve, if the chassis is already out

You do not need to attach photos to the form. A sales rep asks for them in the reply if they help.

Survey the building, not one apartment

A tower that looks uniform from the street often has corner units, penthouse lines, a renovated wing, and a commercial floor with different models. Before a building-wide project, walk one apartment per line and build a short list: line, model number, voltage, heat source. That list is what the board and the managing agent need to approve a phased plan. See planning a building-wide PTAC replacement.

Where the model number leads

The full checklist is in what to send with a PTAC quote request. Model number in hand? Request a quote or call 800-866-1210.

More articles