Our house is a 2 story forced hot water system without ductwork.
Furnace in crawl space or attic.
A furnace can suffer from a drop in energy efficiency if it s in an unconditioned space such as an attic.
As a result their designated space for a furnace is often no longer a.
However not every home has a pre existing designated space for a system.
So when we have a choice we prefer hvac systems located under the house.
Older or historic homes for instance often featured much smaller heating systems than the modern ones we install today.
A two room addition on the 1st floor has limited attic space and a 4 crawl space.
Most homeowners should not place a condensing furnace in an unconditioned space because the unit will produce water as it heats the air.
So why put an hvac system up in the attic at all.
Compare that with the daily 140 degree temperatures found in vented attics.
A basement is below and an attic is above the main part of the house.
The furnace may be placed horizontally in a crawl space on a pad or other noncombustible material which will raise the unit for sufficient protection from moisture.
If the crawl space does not have proper ventilation radon concentrates in the trapped air inside the crawl space.
That moisture can freeze if it receives exposure to exceptionally cold temperatures.
Things seemed to be fine until we had a sustained cold and windy period.
In homes with limited space the furnace can be installed in the attic.
A horizontal furnace in a crawl space must also be elevated approximately 4 6 inches to allow clearance for the.
Even when furnaces are put on the main floor floodwaters often overrun the first floor causing severe damage to the unit.
Rarely will a sealed foam insulated attic deviate more than 15 degrees from the living space temperatures below it.
Most updated central air conditioned homes have a new air conditioner split system meaning the ac is broken up into parts.
Just installing the furnace in the attic crawl way of a single story home gives protection from most flooding.
In flood prone areas instaling a furnace in the attic provides protection.
High efficiency furnaces aren t usually recommended for an attic.
Most of the issues that furnace might experience in an attic are due to extremely cold weather in this poorly insulated space.
The hvac s air pickup is in the crawl space and it spreads the radon laden air into the house.
Well mainly it s a way to save space.
Attic hvac systems save space.
During the fall we disconnected the old furnace and decided to install a new one in our attic space running new ductwork.
The university of maine recommends proper venting of a crawl space to prevent radon gas buildup.
