Cost or Rooftop Install

[kold in kensington]

My building has 20 yeat old rooftop units that have become expensive to run. I am thinking about replacing them. I have 2-25 ton and 1-30 ton unit. It is a three story building with 33,00 SF. They are electric heat and then the individual VAV boxes provide additional heat.

We are in MD. Should my installer be thinking heat pump to lower costs? He is recommending carrier. ANybody have any thoughts on the carrier units?

Thanks


[Edited by kold in kensington on 01-12-2006 at 11:00 AM]

[Jultzya]

Unfortunately, due to site rules (http://hvac-talk.com/vbb/showthread.php?threadid=1241) we as members can not discuss pricing of equipment or installs.

[smokin68]

Have you had them serviced/maintained? I don't know about your area, but here the old units were less expensive to run due to a smaller outside air requirement by code. Ours went from 5cfm per person to 15cfm per person, which meant the units had to be bigger due to the load increase.I can tell you for sure it won't be cheap to replace those.