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falala
Old ducts

I'm looking to have a/c installed but have been told the ducts in my heating system are for heat only. How would central air effect these ducts?

canuk
Re: Old ducts

That's an interesting statement.

Could you elaborate as to why you were told this and by whom?

Re: Old ducts

I'm sure part of the problem is that the duct work in not insulated - in ac mode the duct work would sweat.If the system is in the walls then insulating them would quite an issue. you would need to re rout or re install the duct wory .

falala
Re: Old ducts

In the estimate received from the HVAC installer, they said " the existing ductwork throughout the home is designed for a heat only application" and this would probably limit the performance. We're looking at central a/c for the first floor and mini splits for the second. The house is 100 years old.

canuk
Re: Old ducts
Infraredsurvey.com wrote:

I'm sure part of the problem is that the duct work in not insulated - in ac mode the duct work would sweat.If the system is in the walls then insulating them would quite an issue. you would need to re rout or re install the duct wory .

interesting ... around these parts the metal duct work isn't normally insulated as a basic install and we don't normally see any sweating during A/C use.
Actually if the term " heating only ducts" was used around here there would be plently of chuckling.

I guess it must be a regional thing.

havanagranite
Re: Old ducts
canuk wrote:

interesting ... around these parts the metal duct work isn't normally insulated as a basic install and we don't normally see any sweating during A/C use.
Actually if the term " heating only ducts" was used around here there would be plently of chuckling.

I guess it must be a regional thing.

I will tell you for sure down here an ac duct that wasn't insulated would really sweat like a cold glass of water.

havanagranite
Re: Old ducts

canuk do you even have a need for ac up where you are at? I mean my temp is probally set below the out door temp up there

canuk
Re: Old ducts
havanagranite wrote:

I will tell you for sure down here an ac duct that wasn't insulated would really sweat like a cold glass of water.

Yep ... I can see that having high RH.
I guess if the systems run through the attic space that would also make a difference compared to being in the conditioned space that we normally do here.

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