Residential HVAC Recirculate?

[justsam]

With the fires plaguing both Northern and Southern California, I often hear news broadcasters reminding homeowners to set their HVAC to recirculate, and not allow outside smokey air in the system. I am no HVAC expert but aren't all residential systems basically always operating in a recirculate mode? I have a 2006 vintage Bryant system and I know of no provision to make it anything other than recirculate. Clearly if I opened a door or window than outside air would enter via the return inlet.

Just curious if I am not understanding something, or if newer systems do indeed draw in outside air.

Clearly automotive air conditioning systems have provision for outside air or recirculate, and even air quality sensors to automatically change modes.

 

[larry4406]

My guess they mean set fan to continuous run to filter air 24/7.

But I'm no where near the action so take it with a grain of salt.

 

[48RON54]

Mine always pulls from the dining room register so its always recirculating. Its central air though........I'm not sure if there are other kinds of AC set ups that have that option or not. I'm only familiar with mine and the little window ones.

I often feel like those newscasters just talk to talk and want to scare everyone. Are they saying this so your house doesn't smell like smoke from the fire? Or because there is some health related concern? I don't really get it. We all have to get up and go to work and be outside throughout the day......****** smoky air or not................

 

[dogdog]

It's just saying don't open the windows / leave doors open.... and use your HVAC to filter and circulate the air inside the house...

 

[justsam]

I had not considered just running the fan and let the system recycle the air through the filter. I wonder just how good the average HVAC filter is in terms of removing the smoke odor and particulates associated with these types of fires? My system uses a "lifetime" electrostatic filter which I clean with water about every quarter.

 

[DC73]

. . . I am no HVAC expert but aren't all residential systems basically always operating in a recirculate mode?

Some homes have been built so tight they have to bring fresh air into the home via a damper plumbed into the HVAC system.

These dampers can be adjusted to control the amount of fresh air that enters the house. Disabling the outside air intake by closing the damper effectively returns the system to "recirculate" mode.

DC

 

[Jim greengo]

Some homes have been built so tight they have to bring fresh air into the home via a damper plumbed into the HVAC system.

These dampers can be adjusted to control the amount of fresh air that enters the house. Disabling the outside air intake by closing the damper effectively returns the system to "recirculate" mode.

DC

 

[LS6 Tommy]

Some homes have been built so tight they have to bring fresh air into the home via a damper plumbed into the HVAC system.

These dampers can be adjusted to control the amount of fresh air that enters the house. Disabling the outside air intake by closing the damper effectively returns the system to "recirculate" mode.

DC

DC73 is correct, but in terms of listening to a news broadcaster, when have you ever known one that actually knew what they were talking about?

Tommy

 

[Jim greengo]

 

[03.]

DC73 is correct, but in terms of listening to a news broadcaster, when have you ever known one that actually knew what they were talking about?

Tommy

Absolutely nailed it

 

[96PSD]

I think they also were referring to more business type systems that usually are required to have a 15% fresh air intake mixed into the recirculating air. Facilities like schools and office buildings are tight with glass and CO2 can build up with large capacities of individuals.