Cold air return in basement

[Jody]

Hello there, We have a forced hot air variable speed furnace. We just had an HVAC company put 3 heating vents and 2 returns in our finished basement. The basement is about 1000 sq.ft. We have been told that our furnace should be sufficient to heat the basement. However, we have a very cool basement. The heat ducts are on the exterior wall at the floor and the returns are on the same wall but near the ceiling. We thought the returns should be on the floor since cold air sinks. Our HVAC guys argue that the returns are on the top of the wall to create airflow/air pressure. Are they correct? We no longer trust their judgement since our basement is so cold, but they are willing to come back and make adjustments. Where should the returns be? Also, would it help to cut additional heat vents out of the main duct on the ceiling? What do you suggest they do? Thanks so much for your time.

[Joseph Meehan]

I am no pro here, but I would think the returns would be more effective on the opposite side of the room away from the outside and close to the floor.

[m Ransley]

Im not a Hvac pro but have done basement remodeling. I dont think it is worth an argument over placement , you will have circulation. but you do need them to add more supplys to just get in more heat, and they agreed to do that.

A thing I have found is on many remodels, basements are cool if underground completely, on my last one I had to remove and insulate all the ducts as even with the vents off the basement needed a heater in summer just from the cold air passing through to the upstairs, I hope you considered this. Many basements just need a Dehumidifier and the return open in summer as humidity is the issue when it is warm out.

[Goedjn]

I think they did it backwards, myself. If the returns are above the supply, then the warm air can just come out of the vents, up the wall, and through the returns, never touching the rest of the basement. That only works if they do *ALL* the walls, so that the basement is in an envelope of warm air. If they can swap the returns and supply, that's one way to fix it.

>

[Jody]

Okay, does anyone know how to fix the problem?

[Joseph Meehan]

To fix the problem takes a professional with some experience who knows what they are doing and does the work (math) to measure what you really need. Clearly the one you had did not.

My only suggestion is to ask around to find a good professional as recommended by people who have used them.

They should do a manual J and manual D computation. Somehow I doubt if the one you had bothered, or maybe does not even know what they are.

[Jody]

[Kathy]

Have you tried to speak to the owner of the company? Maybe you didn't get to talk to the right person and the owner doesn't even know he has an idiot working for him. I Googled around a little and it was easy to find several plans for ductwork and even though some of them had both floor and ceiling supply ducts, they ALL had returns at or near the floor. Some also had returns up high for air conditioning.

[Jody]

[Joseph Meehan]

All you need do is bring him down there and ask him why HIS system is not working. If it were working you would be warm and comfortable.

No you don't. You are right He is wrong. If you fails to follow up quickly, it is time to take the issue to his licensing board.

[m Ransley]

You dont need to do anything but get him to provide more heat-vents. You are second guessing him and should just let him fix it. It will work with your returns , you need more supply.

[Jody]

The thermostat is on the first floor, not on a separate thermostat. I can't get any more heat vents on the floor as the basement is not finished. All I can do is cut additional ones in the ceiling to add more heat. The other thing I could do is move the returns to the floor. You are right about the cold feet. That is why I had the HVAC guys come in and put ducts from the main vent on ceiling down to the bottom of the walls. I assumed he would know how many would be suffient and on which walls to put them. That is why I paid for a professional to do it, to avoid having a cold basement. It really sucks when you pay a professional to do something and they screw it all up and then think they are still right.

And, thank you, I am having a nice day:)

[Jody]

Zoning system sounds expensive. We really can't afford to sink any more money into this basement. I don't know much about balancing.

[nicksanspam]

The return vents on a heating system should be near the floor on outside walls because cool air falls and loses less energy to the outdoors. The supply vents should be near the ceiling on inside walls, keeping warm air away from cool walls and taking advantage of flow due to warm air bouyancy.

Nick

[Joseph Meehan]

I would not assume that more heat vents or moved heat vents or any specific fix is needed. What is needed is a comfortable basement. How that is accomplished is the job of the contractor. Telling him how to do his job is only asking for and deserving and answer later, that "I did what you told me so my job is done, it is not my fault it did not work"

[m Ransley]

I agree JM, but if it isnt more supplys then what? It has to need more supplys , it is near 60 and 3 are what they have that were routed to the floor. I agree dont direct the Pro but more supply is logical, I just finished my underground basement and kept putting in more supplys till it equaled the upstairs. I have 3 very large for 600sq, they have 3 for

1000. Their easiest and cheapest rout is more supply.

[Joseph Meehan]

It's really hard to say from here. The only viable solution may be some form of zoning or supplemental heat. Maybe the current system is really not large enough to handle it. Additional returns, larger or more ducts. Just adding more supplies from the same duct, may just screw up the heat to the second floor. As I said, I can't see it from here, and frankly, I would call a pro in since I don't have the experience or training to do it. I have to admit I have done it a couple of times and it has turned out very well, but I would guess that was more accident than anything else.

In the end, it may be just more supplies, I know of no reason it could not be.

[Goedjn]

If the room is uniformly cooler than desirable, then that's a supply issue. If the floor and back of the room is noticably cooler than the ceiling and register-side of the room, then thats a circulation and insulation issue.

[nicksanspam]

Thus exploding the house? :-) Utterly ridiculous...

Nick

[Jody]