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Be sure your ducts are delivering all the warm air they can!


According to EnergyStar, about 20% of the air moved through duct work is lost through leaks! Leaks should be sealed and ductwork in a cold basement, crawl space or attic should also be insulated!


Suggested ductwork improvements:


Check, measure and identify all duct leaks

Seal duct leaks and seams with mastic sealant or metal tape

Replace or repair and damaged, disconnected or undersized ducts

Straighten out or replace any crushed or twisted flexible ducts

Seal all registers and grills tightly to the ducts

Insulate all ductwork in unconditioned spaces with an R-8 duct insulation...which is NH code!


Visit EnergyStar for more information about duct sealing and HVAC system efficiency.


EnergyStar "Duct Sealing" Brochure



Return Air


Be sure your HVAC system has adequate return air to keep your home balanced. Negative pressure can draw carbon monoxide from gas appliances in homes with inadequate returns. A carbon monoxide detector is highly recommended.

commercial duct install NH
commercial duct install NH (2)
Commercial duct installation NH 2012
Nick and Dave, new construction
new construction duct
ceiling return grill

Typical return air grill

ceiling supply register

Typical ceiling supply

Contact us today to schedule a quote or request service!

Proudly serving the Milford NH

area including:


Amherst NH

Bedford NH

Brookline NH 

Francestown NH

Greenfield NH

Greenville NH

Hancock NH

Hollis NH

Lyndeborough NH

Mason NH

Merrimack NH

Mont Vernon NH

New Boston NH

New Ipswich NH

Peterborough NH

Temple NH

and Wilton NH

"We were so lucky to have found such honest people!  The Card's came to our house twice quite late at night to work on our furnace which we greatly appreciated due to our "out-of-date" furnace.  Our basement was an absolute nightmare until Mike's sons installed new (neatly fabricated) duct work as well as a new furnace.  I would strongly recommend Card Heating & Cooling!  They take pride in their work and do a fantastic job!  Thank you Card family!"


Ralph & Nicole Porter

"Mike, I just wanted to let you know...we decided to go through an energy audit for the house (nothing related to the heat - we just wanted to be more efficient.  Anyway, the point is, the fellow came today and did a bunch of tests on the house.  He commented (several times as a matter of fact) about how well done the duct work was, how well the heating system was tuned, etc. etc.  One specific comment from him was that the ductwork you did is 'exceptional' and the state of the burner was much better than he's used to seeing in a typical home'.   I just thought you'd want to know.  Thank you for all your had work...being a homeowner, it's hard to know an exceptional job vs. an average one.  But since this guy's job is to inspect these things, thought you'd appreciate what he had to say."


Ed, Amherst NH 

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