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Preston's began publishing the HVAC specs guide in 1996 and quickly became the industry bible for replacement are some comments from HVAC dealers and contractors as well as home inspection professionals.


"A few things I would not be without on a service truck are 1.) a current edition of the Preston's Guide and 2.) a thermostat cross reference with wiring guide that Honeywell has."    - James 3528 member


"Our replacement business volume (and profit from it) has increased each year. Preston's Guides certainly helped us achieve this"  

- New England Plumbing/HVAC contractor

"The Guide provides me with an easy way of showing customers the energy-costs one of my new units will save them"  

- Midwest HVAC contractor

"Preston's is the only source where I'm able to find the age, capacity and efficiency ratings of so many old HVAC units. Essential information when selling in the replacement market."  - Member, Contractor's Success Group

"I didn't know there were so many brands made over the past 40-45 years!"
- Ad Manager for a major A/C and Furnace Manufacturer

"This kind of comprehensive data doesn't exist anywhere else!"  - Editor, weekly HVAC/R trade publication

"I recently updated my Twin-Volume to the 2005 edition and it makes me look smarter when I’m talking about servicing or replacing a customer's existing equipment."  - bshm member

"You can't be totally effective selling HVAC replacements without the Preston’s Guide"  - Sales Rep for national retailer, Winter Park, FL

"I bought nine Guides so that each of my service technicians can have it with them for quick reference"  - HVAC contractor, Charlottesville, VA

And, what Home Inspection Professionals are saying about Preston's Guide:
"The Preston’s Guide lists units for every year they were made and that helps me determine the age of old cooling and heating equipment in homes I’m inspecting and reporting on"  - Independent Home Inspection Professional, Ridgefield, CT

"When I attended the Home Inspection Institute, they told us "get The Preston's Guide as soon as you open for business. And, I did."  - Independent Home Inspection Professional, KS

"I bring The Preston's Guide right to the inspection site in the form of their CD-ROM loaded onto my laptop. I take that everywhere."  - Independent Home Inspection Professional, Danville, IL

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