Moving air around - options?

[TradEddie]

I hope I can benefit from the experiences or even mistakes of others here before I start my next project. I have a 2000sqft cape with an insert in the kitchen at one end of the house. The floor plan does not lend itself to much natural convection. If that insert is cranking on a cold day it can be 85F in the kitchen, but high 60s in other rooms. I run my central air in “fan only†mode to help move air, but my system is a retrofit and not ideal. I have modified the returns to draw more air from the kitchen and increased the fan speed setting, but between mixing with colder return air and heat loss in the ducting it’s hard to get any more than 68F to the supply registers in other rooms. I’m afraid to close off all the other return registers in case that overloads the furnace fan, and I wouldn’t want to keep resetting registers when I use central air heat on weekdays.

I have easy access to a soffit space above my kitchen and am considering either a booster fan for that return register, or a separate dedicated duct drawing air from the kitchen to the top of the stairs.

Has anyone successfully tried anything like this? Are those booster fans noisy? How much CFM is really needed to make a difference?

TE

 

[pen]

Because of the downfalls you mentioned, using ductwork to move hot stove air often doesn't do much good. Some folks have had luck with it over the years, but far more find it just doesn't work.

In general terms of moving air, here is a link that may be helpful to you. https://www.hearth.com/econtent/index.php/forums/search_results/131277d0f15be0d8def0ac918e78a9ba/

pen

 

[madison]

If by retrofit you mean that the air handler and the ducting for the A/C is in an "unconditioned space" (ie attic) the heat loss to the attic can be substantial via the poorly insulated ducting and air handler , and all the typically leaky connections between duct work etc.

some users report success, most do not.

A simple search of this site will reveal lots of responses to this same exact question.

 

[PapaDave]

I have insulated flex duct with an inline fan setup from the stove room to the middle of the house in the attic. Once the stove room gets warm, it works well, but can be a bit noisy when run at a hougher speed.
It's on a dimmer switch, and I keep it on low most of the time (when it's running).
On the other hand, we got a room air purifier w/3 speed fan and point it into the stove room. I keep that on low. Cleans the air of dust and dog hair (lost my hacking cough), and circulates the air to the back of the house very well. The back bedroom used to stay about 60, but it now is pretty steady at 63-65. Win, Win.

 

[madison]

On the other hand, we got a room air purifier w/3 speed fan and point it into the stove room. I keep that on low. Cleans the air of dust and dog hair (lost my hacking cough), and circulates the air to the back of the house very well. The back bedroom used to stay about 60, but it now is pretty steady at 63-65. Win, Win.

Good idea on the air purifier, i use my console humidifier. Your added ducting is within the living envelope?

 

[PapaDave]

The flex duct is in the attic and insulated. It was here when we bought the place.
Moves a goodly amount of air and is quite warm as it exits the ceiling registers in the kitchen and bathroom.

 

[TradEddie]

PapaDave, which direction do you run that dedicated duct? It seems like people have had more success forcing cold air into the stove room, than sucking hot air out.
I have insulated my central air ducts, so I only lose a degree or two from the furnace inlet to the supply registers, so if I could just get more of that 85F air into the returns...

TE

 

[PapaDave]

The inline fan is about 20' from the stove room and pulls from the stove room and y's just past the fan. One leg goes to the kitchen and one to the bathroom.

 

[DexterDay]

Tjernlund Aireshare. Look them up. They have room to room fans and level to level fans.

I installed an Aireshare room to room fan and also a Broan Room to Room fan. Both work great. But the Aireshare is Much quieter (costs more too).