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So we don’t have air conditioning. Need it for about 2/3 months a year. We have one of those free standing ones that’ll do a room or two. My strategy is the basement is usually about 65° all summer. If I run the air conditioner in the basement (65° + AC unit set at 65°) will the furnace fan draw from the basement and cool the whole house to a reasonable temp and be able to “keep up”

Or will I die? Will update.

Get cross ventilation through your house with windows.
Awnings and cover the windows from direct sunlight to prevent heat gain.

Install VRF cooling systems to reduce energy consumption.

https://www.ferguson.com/content/trade-talk/tricks-of-the-trade/what-is-a-vrf-system

AC is a heat pump, so it is just pumping hot air from inside to the outside. In doing so, it creates a cold "coil" that air is blown over to distribute cool air through the house.

Furnace fans use cold air returns from the rest of the house, not just the basement.

In theory, if you could re-duct the cold air return around the AC unit, it would work, but to what degree?

The cooling ability of your unit is WAY too small to cool the entire house effectively. Think of it as using a cigarette lighter to boil a pot of water. Or a single ice cube to cool a pot of boiling water.

Does your HVAC system have zones and a fan only function?

The problem is your fresh air makeup is from the outside and that will be the airtemps you are pushing through the rest of the house. Unless you reduct your fresh air to draw air from the basement and not outside air your system will be cooling outside air not drawing the air from the cooler basement.

NumbersDude wrote:Does your HVAC system have zones and a fan only function?

The problem is your fresh air makeup is from the outside and that will be the airtemps you are pushing through the rest of the house. Unless you reduct your fresh air to draw air from the basement and not outside air your system will be cooling outside air not drawing the air from the cooler basement.

Assuming his house has an ERV, yes. Otherwise the cold air return is primarily from the living spaces on the floors above the basement. Unless the basement is finished, but it's still only going to be a small percentage of return air coming from the cooled rooms.

Tapping in to answer the question.
Reads the question.
Tapping out.

Motown Spartan wrote:AC is a heat pump, so it is just pumping hot air from inside to the outside. In doing so, it creates a cold "coil" that air is blown over to distribute cool air through the house.

Furnace fans use cold air returns from the rest of the house, not just the basement.

In theory, if you could re-duct the cold air return around the AC unit, it would work, but to what degree?

The cooling ability of your unit is WAY too small to cool the entire house effectively. Think of it as using a cigarette lighter to boil a pot of water. Or a single ice cube to cool a pot of boiling water.

What about just leaving the fridge door open?

kingstonlake wrote:If I run the air conditioner in the basement (65° + AC unit set at 65°) will the furnace fan draw from the basement and cool the whole house to a reasonable temp and be able to “keep up”

Or will I die? Will update.

Probably both

So in a nutshell you guys are saying that running the furnace fan only will be a minimal draw from the basement? It’s actually drawing from the rooms upstairs via return air ducts?

Just put ice on your balls

ummm.. is anyone not going to tell him to 'stop being poor'?

y'all are lettin' us down.

kingstonlake wrote:So in a nutshell you guys are saying that running the furnace fan only will be a minimal draw from the basement? It’s actually drawing from the rooms upstairs via return air ducts?

Yes.  

Motown is spot on, your furnace is essentially drawing no air from the basement other than leakage.

Look at where your furnace filter is - that is where you blower is drawing air from and it will be at the end of your "cold air return." Regardless if your system is drawing outside air or not, returns typically do not draw air from the basement. You are just wasting money.  In theory you could bypass it, but don't. Just don't.

While you are down there looking at it, change the filter - because it has probably been awhile.

What about just leaving the filter out and the little door open? then it would HAVE to suck the cold out of the basement...

(Throwing wall shit)

AvgMSUJoe wrote:What about just leaving the filter out and the little door open? then it would HAVE to suck the cold out of the basement...

(Throwing wall shit)

along with the humidity

AvgMSUJoe wrote:What about just leaving the filter out and the little door open? then it would HAVE to suck the cold out of the basement...

(Throwing wall shit)

First off, you should not run the blower without a filter in place.  The filter is there for a reason - to protect the system (not really to make you house less dusty but this will happen if you remove it).  Without it you will add dust and dirt where they should not be, on the blower motor and in your duct work.  This is especially true if you have pets.

Secondly, you would suck some air from the basement in this scenario, but probably not as much as you think.  The filter opening is much smaller than the cold air return and the cold air return is in a direct line.  The return system is going to there even if you remove the filter and door.  Again, you could in theory bypass it - just don't.  The cooling effect would in a likelihood be minimal.  It would depend on a number of factors - especially where your duct works runs and how insulated it is.  It is simply not an efficient way to cool a house.

kingstonlake wrote:So we don’t have air conditioning. Need it for about 2/3 months a year. We have one of those free standing ones that’ll do a room or two. My strategy is the basement is usually about 65° all summer. If I run the air conditioner in the basement (65° + AC unit set at 65°) will the furnace fan draw from the basement and cool the whole house to a reasonable temp and be able to “keep up”

Or will I die? Will update.

If the basement is usually 65° and you set the AC unit to 65° in the basement, why would you think the upstairs could be cooled more than without the AC unit?

Plus, count the number of cold air returns in the basement (possibly zero). Divide by the number of returns upstairs to calculate the approximate % of air coming from the basement.

If you want to cool the house using some help from the basement, install an attic fan.

The Pantry wrote:
install an attic fan.

This

Nordic wrote:

The Pantry wrote:
install an attic fan.

This

What’s the best kind and at what cost?
Turbine?
Solar?
My central air doesn’t do the trick upstairs. Maybe a 4 degree difference. More on hot days. I’ve covered vents with magnets in various spots that aren’t used but it just doesn’t get to the bedrooms like we’d like it to.

DWags wrote:

Nordic wrote:

This

What’s the best kind and at what cost?  
Turbine?
Solar?  
My central air doesn’t do the trick upstairs. Maybe a 4 degree difference. More on hot days. I’ve covered vents with magnets in various spots that aren’t used but it just doesn’t get to the bedrooms like we’d like it to.

My house iw 30yrs old. It's just a standard electric attic fan mounted in master closet. It is mounted interior, not exterior.

When you want air out your house just turn it on for 10-30mins..Pull the shades during the day and turn on the fan when the sun gies down. Also worked good for air circulation during our bouts with covid. Crack a door and put it on low. No one else got sick.

I would never have another home without one.

https://www.homedepot.com/p/Maxx-Air-11-in-x-28-5-in-2985-CFM-White-Galvanized-Steel-Automatic-Shutter-Whole-House-Fan-CX242DDWT/203931068?g_store=&source=shoppingads&locale=en-US&&mtc=Shopping-CM-F_D22-G-D22-022_010_ROOFING-NA-NA-NA-SMART-2996810-WF-New_Engen_PL3&cm_mmc=Shopping-CM-F_D22-G-D22-022_010_ROOFING-NA-NA-NA-SMART-2996810-WF-New_Engen_PL3-71700000082418319-58700006968767411-92700070898422791&gclid=Cj0KCQjwvqeUBhCBARIsAOdt45YKMImkUcLXr8rkUbngC5sbyuj6uo6MHdzduiYbSlRdFXmcdOAvDKQaAvFbEALw_wcB&gclsrc=aw.ds

The Pantry wrote:

kingstonlake wrote:So we don’t have air conditioning. Need it for about 2/3 months a year. We have one of those free standing ones that’ll do a room or two. My strategy is the basement is usually about 65° all summer. If I run the air conditioner in the basement  (65° + AC unit set at 65°) will the furnace fan draw from the basement and cool the whole house to a reasonable temp and be able to “keep up”

Or will I die? Will update.  

If the basement is usually 65° and you set the AC unit to 65° in the basement, why would you think the upstairs could be cooled more than without the AC unit?

Plus, count the number of cold air returns in the basement (possibly zero).  Divide by the number of returns upstairs to calculate the approximate % of air coming from the basement.

If you want to cool the house using some help from the basement, install an attic fan.

I was wondering if running the AC unit in the basement would help keep/supplement the basement at 65° When needed if I were constantly drawing from the basement. The AC unit is one of those free standing units and usually only cools one room or an area. Thought maybe drawing from the basement with registers in every room upstairs would potentially cool the whole house to a reasonable temp. Not looking to cool the whole house to 65° just bring the temp down to a reasonable number.

kingstonlake wrote:So we don’t have air conditioning. Need it for about 2/3 months a year. We have one of those free standing ones that’ll do a room or two. My strategy is the basement is usually about 65° all summer. If I run the air conditioner in the basement (65° + AC unit set at 65°) will the furnace fan draw from the basement and cool the whole house to a reasonable temp and be able to “keep up”

Or will I die? Will update.

Came to this thread way too late, all the good ideas, and bad ones, are taken.

Some forced air systems have dampers inline to each outlet, if so shut the ones to the first floor and open the ones to the second. Also, some outlets have dampers built into them, shut all the first floor ones, open all the second floor ones.

Whole house fans and air conditioning don't play well together, as the whole house fan will suck out all the cold air along with the warm and pull in whatever the outside air temperature is.

Proper use of whole house fan is for when the outside air is cooler than the air in the house, typically at night, and then open the windows and turn the fan on.

Attic vent fans, btw, also don't play nice with air conditioning as they pull cool air from the house into the attic, so unless you are trying to air condition your attic to keep your roof cooler, shut them off.

How about insolating the attic, or adding more if insolated?

Yeah it doesn’t look like there’s any return air vents drawing from the basement. Scratch idea!

kingstonlake wrote:Yeah it doesn’t look like there’s any return air vents drawing from the basement. Scratch idea!

Get a large fan. Blow cooler air from the basement to the first floor of your house. But exhaust the warmer air to the outside.

kingstonlake wrote:Yeah it doesn’t look like there’s any return air vents drawing from the basement. Scratch idea!

Cut a hole in one of the cold air returns, a big one, near the furnace?

NumbersDude wrote:

kingstonlake wrote:Yeah it doesn’t look like there’s any return air vents drawing from the basement. Scratch idea!

Get a large fan. Blow cooler air from the basement to the first floor of your house. But exhaust the warmer air to the outside.

Sort of hard to get cool air to a place warn air wants to be, unless the fan is forced to have its lower pressure points in the basement the air will just come from the area around the fan.

Whole house fans will not draw from the basement either, unless there are big open windows in the basement.

Nordic wrote:My house iw 30yrs old. It's just a standard electric attic fan mounted in master closet. It is mounted interior, not exterior.

When you want air out your house just turn it on for 10-30mins..Pull the shades during the day and turn on the fan when the sun gies down. Also worked good for air circulation during our bouts with covid. Crack a door and put it on low. No one else got sick.

I would never have another home without one.

FWIW, there is a significant difference between a whole house fan (what you are describing) and an attic fan. A whole house is mounted in the interior of the home and draws air from the house which is moved to the attic. An attic fan is mounted on the roof or in a gable and draws air from outside into the attic. A whole house fan is usually turned on by the homeowner with switch, and attic fan is usually turned on via thermostat in the attic.

An attic fan is a good way to vent an attic (especially with a hip roof), but THEY SHOULD NOT BE INSTALLED IF YOU HAVE A RIDGE VENT. It really is one or the other. If you have an attic fan with a ridge vent, it will pull most of the air from the ridge vent instead of the soffits and much worse, it can/will pull in rain from the ridge vent if it is raining.

MSU addict wrote:

Nordic wrote:My house iw 30yrs old. It's just a standard electric attic fan mounted in master closet. It is mounted interior, not exterior.

When you want air out your house just turn it on for 10-30mins..Pull the shades during the day and turn on the fan when the sun gies down. Also worked good for air circulation during our bouts with covid. Crack a door and put it on low. No one else got sick.

I would never have another home without one.

FWIW, there is a significant difference between a whole house fan (what you are describing) and an attic fan. A whole house is mounted in the interior of the home and draws air from the house which is moved to the attic. An attic fan is mounted on the roof or in a gable and draws air from outside into the attic. A whole house fan is usually turned on by the homeowner with switch, and attic fan is usually turned on via thermostat in the attic.

An attic fan is a good way to vent an attic (especially with a hip roof), but THEY SHOULD NOT BE INSTALLED IF YOU HAVE A RIDGE VENT. It really is one or the other. If you have an attic fan with a ridge vent, it will pull most of the air from the ridge vent instead of the soffits and much worse, it can/will pull in rain from the ridge vent if it is raining.

As long as the attic is properly vented for the attic fan, if it is too tight it will pull air in from the house.

DWags wrote:

Nordic wrote:

This

What’s the best kind and at what cost?
Turbine?
Solar?
My central air doesn’t do the trick upstairs. Maybe a 4 degree difference. More on hot days. I’ve covered vents with magnets in various spots that aren’t used but it just doesn’t get to the bedrooms like we’d like it to.

Please see my warning about attic fans and ridge vents.

A 3-4 degree difference is pretty normal in a two story house, especially with dark shingles. You are correct that the largest part of the problem is the heat in the attic. Most likely you see the bigger temp differences on sunny days as the attic heats up a lot on sunny days. I have a remote thermometer in the center of my attic so I can monitor the temps up there.

Make sure your soffit vents are not covered and are adequate. If they are covered by insulation that is not hard to fix - but if they simply are not adequate (or nonexistent) that is not easy/cheap to fix. As Trapper Gus has suggested, make sure you have adequate insulation. If not, that is probably a cost effective fix as it will help a lot with your heating bills as well.

A relatively cheap and easy solution is to add a register vent fan in the problem room.

Something Like This

That should make a 2-3 degree difference. The problem is they are pretty loud for a bedroom. You can also add an inline booster fan - but that is a bit more complicated as you need to run electricity to it and ideally it will wired to turn on only when the blower is on (they can also be controlled with a separate thermostat).

Trapper Gus wrote:

MSU addict wrote:FWIW, there is a significant difference between a whole house fan (what you are describing) and an attic fan.  A whole house is mounted in the interior of the home and draws air from the house which is moved to the attic.  An attic fan is mounted on the roof or in a gable and draws air from outside into the attic.  A whole house fan is usually turned on by the homeowner with switch, and attic fan is usually turned on via thermostat in the attic.  

An attic fan is a good way to vent an attic (especially with a hip roof), but THEY SHOULD NOT BE INSTALLED IF YOU HAVE A RIDGE VENT.  It really is one or the other.  If you have an attic fan with a ridge vent, it will pull most of the air from the ridge vent instead of the soffits and much worse, it can/will pull in rain from the ridge vent if it is raining.  

As long as the attic is properly vented for the attic fan, if it is too tight it will pull air in from the house.

You are correct.  Most attics simply do not have adequate soffit ventilation (especially homes 30+ years old).  Most attic fans will pull cooled air from the home - the amount depends on the home.  It may not be the most efficient but the upper floor of your home will be cooler.

Robert J Sakimano wrote:ummm.. is anyone not going to tell him to 'stop being poor'?

y'all are lettin' us down.

This. This right here. We will let anybody post here. This place has been overrun by the poors. Does anybody have the link to SD24759303648's elite board?

MSU addict wrote:

Nordic wrote:My house iw 30yrs old. It's just a standard electric attic fan mounted in master closet. It is mounted interior, not exterior.

When you want air out your house just turn it on for 10-30mins..Pull the shades during the day and turn on the fan when the sun gies down. Also worked good for air circulation during our bouts with covid. Crack a door and put it on low. No one else got sick.

I would never have another home without one.

FWIW, there is a significant difference between a whole house fan (what you are describing)

Yes this

I said attic but meant whole house fan.

Turtleneck wrote:

Robert J Sakimano wrote:ummm.. is anyone not going to tell him to 'stop being poor'?

y'all are lettin' us down.

This. This right here. We will let anybody post here. This place has been overrun by the poors. Does anybody have the link to SD24759303648's elite board?

SD looks like a numbers guy.

The Pantry wrote:I said attic but meant whole house fan.

Same. I knew watcha meant

kingstonlake wrote:

Turtleneck wrote:


This. This right here. We will let anybody post here. This place has been overrun by the poors. Does anybody have the link to SD24759303648's elite board?

SD looks like a numbers guy.

What you did there— I seen it.

Turtleneck wrote:

Robert J Sakimano wrote:ummm.. is anyone not going to tell him to 'stop being poor'?

y'all are lettin' us down.

This. This right here. We will let anybody post here. This place has been overrun by the poors. Does anybody have the link to SD24759303648's elite board?

I am a poor. Send me 10k.

Nordic wrote:

The Pantry wrote:I said attic but meant whole house fan.

Same. I knew watcha meant

1st house (no AC) I bought had one in the hallway outside the bedrooms. Worked pretty well in the evening after opening the windows...except for spring/summer of 1988 which was really hot. Fortunately the basement was carpeted and semi-finished. We had a bed down there for really hot nights. Basement was at least 10° cooler than the main floor.