Air Return vent floor level, should they be moved?

[mollyfg2000]

Last year I responded to one of the ad's in the newspaper to have my Central Air unit checked and cleaned for I think about $30, which has nothing to do with my question:) Of course the guy told me my unit was old, which it is but still runs good and cools the house, but he said that I should have a new one installed for various reasons. After I declined his offer of installing a new unit he said that my house was old and the air returns vent are on the floor in the hall and should be closer to the ceiling, which he offered to do for several hundred dollars. I know the concept hot air rises and the suggestion makes sense. There is a hall light right above the two air return vents. I ask him why I couldn't have someone install a hall ceiling fan for me to push the hot air down to achieve the same purpose. He said that was the silliest idea he had ever heard anyone come up with. The conversation went down hill from there and I ask him to leave my house. He may have very well been correct and it won't work, but no one likes to be called stupid. Any thoughts on this idea, will it work? Would it be cost effective to have the vents moved closer to the ceiling? Where I live we have many days a year that are 90 degrees and higher Thanks Molly

[indago]

Of course, ideally, the air circulating system would have the return air for a heating system at a high level, and the room vents low; and for air conditioning, the return air vents low and the room vents high. Your system will work "efficiently" for air conditioning. If it ain't broke, don't fix it.

If the same air circulating system is used for heating, then the high room vents should have louvers on them to direct the air downward, and the circulating fan should have enough "push" to move the air down toward the floor. Of course, the warm air will eventually rise back up again. It would be well to get a thermometer and measure the temperature close to the ceiling and on the floor during the winter to see if there is a substantial difference. Some leave the air circulating fan running all the time during the winter to keep the rooms at a more even temperature. This dries out the air, and a good humidifier may be necessary to put more humidity back into the air.

[mark Ransley]

Im no ac pro , but if you are cool that is what counts, ceiling fans help alot , any fan that moves air should make you more comfertable, my returns are in the floor and work, maybe modern design recomends them higher, but If you are comfortable why bother

[John W. Wells]

Well, now he has an even sillier one--namely, that humiliating a potential customer is a way to close the sale!

Atta Grrl!

--John W.Wells

[D-]

floor in the hall and

(That remark wouldn't have offended me. In a way he was right and didn't mean to offend you.) Don't put a ceiling fan in a (small non living area) hallway, always put a ceiling fan in your main living area, it will mix the air in the larger area and keep you feeling cooler, as well.

An air conditioning system will do a better job circulating the air and removing the heat and moisture if the return air intakes are nearer to the ceiling, not the floor. Most older homes in the north have both supply and returns at the floor level, In some cases the cooled air merely travels across and into the return known as recirculating the coolest air, which at given CFM airflow can reduce the heat absorbing capacity of the evaporator coil. Also temperature drop may not be enough to condense sufficient amounts of moisture from the air. I would much prefer a switch-able Return and Supply system..

If it's a round discharge condenser check the temperature rise/split off it during the highest heat load time of day and let us know what it is. Does the condenser run all the time even when it is not real hot and/or humid?

Most homes have 8 foot ceilings, if you have very high ceilings put the returns at around the seven foot level. and leave the air near the ceiling alone. I personally would have had him switch them, and I don't get offended by another person's comments. - Darrell - Retired A/C contractor and tech

[Alan]

If the system keeps you comfortable now, I would leave it as it is. On the other hand, if you find the temperature at floor level much cooler than higher up, you may wish to install ceiling fan(s) in whichever room(s) it is a problem or spend a lot of money putting return air vents closer to the ceiling. I don't think it is worth it to move them and like your idea better, although not necessarily only in the hall.

>

[Joseph Meehan]

"..but still runs good and cools the house .."

That's your answer. The second bit of advice is don't call that company out when it is time to get a new system. Find a good tech. That will be the time when you should consider the additional or modified duct system.

I doubt if adding high returns would be a bad thing and it likely would be good, but it would be even better to have someone review the whole system and suggest a total plan, not a patch.

It is up to you when the time is right for a new system. Maybe when the one you have dies, maybe when the heating system goes south. Maybe when you win big at the track.

['nuther Bob]

15000 sq feet ? You must have laid out some serious cash for that!

Bob

[mollyfg2000]

Sorry posted before my coffee this morning. I only wish I had a 15000 sg foot house. Of course I had to many zero's,,,

1500 is what I have, and yes I know that you were just teasing me.

[C. Brunner]

On Mon, 07 Jul 2003 14:19:12 GMT, [e-mail] wrote: [snipped]

We built a 2500-sf "custom" house 5 years ago, and were faced with the same question. We live in Alabama, where there are way more cooling days than heating days, and we have two heat pumps. Our contractor suggested putting the air returns in the ceilings, rather than at floor level, but I don't think his preference had anything to do with efficiency. He seemed to be more concerned about aesthetics. Specifically, he wanted to hide the returns in the ceilings of the

*master and guest bedroom closets*! We were concerned what that would do to airflow if the closet doors were closed, not to mention the hassle associated with changing the air filters, which would be inside the return vents installed in 9-foot ceilings. He said it wouldn't be a problem, because we had specified louvered closet doors; and most homeowners didn't change their air filters very often, anyway.

We asked the HVAC subcontractor what *he* would recommend, and he said the system would work much better if the return vents were installed at the base of walls at the ends of hallways. He acknowledged that they didn't look "pretty", but said the airflow would be much better and the filters would be easily accessible.

C. Brunner

[Joseph Meehan]

Well I doubt if many of his customers change them often, when he installs them in a way that makes it difficult.

[Tim Fischer]

That makes sense. If you want to be even more efficient, you can block off the appropriate returns for the season (e.g. the lower floor ones during the cooling season). That way you're always conditioning the air that needs it the most.

-Tim

['nuther Bob]

I assume there's an automatic damper that will switch to a different floor of returns depending on whether you are heating or cooling ? Otherwise one floor is always in the wrong state.

If the system is designed to do that, there should be an automatic damper doing it with heating or cooling. If you do that to a system that was not designed for it, you will damage the system due to a lack of airflow.

Bob