No Data Tag, No Problem

Q: “I need to replace this RTU but there is no data tag (or it’s not legible). How do I know what size unit I need?”

With no data tag, it’s hard to know what the existing RTU size is, but with enough information, you can usually get close. 

Here are 8 pieces of information to collect on site if you can’t find the existing model number. The more you gather, the better chance you have of determining the correct size.

  • Compressor model number(s)
  • Square footage of evaporator coil face area (fin area only)
  • Electrical circuit size (amps), including the fuse size
  • Supply fan motor horsepower 
  • Main supply duct size 
  • L x W of existing roof curb
  • Size of space being conditioned
  • Heat type (Gas/Electric/Heat Pump/No Heat)

Now that you have this information, you have two options…

Option 1
Call or send us a message and we can help determine the existing size.
Option 2
Download this tool and do your best to match the existing information, then Call or send us a message for a quote

The linked tool includes data from York RTUs circa 2000 including electrical, fan motor sizes, evaporator coil surface areas and more.

This tool also includes links to popular compressor manufacturer model breakdown PDFs to help determine existing cooling capacity. 

Whether you’re confident you determined the correct existing size or not, we still recommend doing a load calculation prior to quoting a replacement. A lot of equipment is on its 3rd or 4th tenant, or the building design may have changed since the original installation. 

➡️ Are you working on a job that we can help you with? If so, shoot us a message or Call 1-800-322-9675 to be put directly in touch with one of our sales engineers

Brad Telker
Connect on:
Latest posts by Brad Telker (see all)
This entry was posted in Helpful Tips, Products, Rooftop Units and tagged , , , on by .
Back to blog