Please advise on how to cool upstairs in my 1950s house

[Lynette]

I would appreciate advice on how to cool the upstairs of my house in Michigan. It is a 1400 sq foot bungalow that was built in 1950. Probably 60% of the small houses like mine in my neighborhood have been torn down and replaced by houses costing from $1 to 1.5 million.

I had a new Bryant furnace and air- conditioner installed in September 2021 by a reputable local HVAC company. It cost about $10,000 with rebates for being energy efficient. I had problems with the heat upstairs with my first HVAC, the second one seemed OK. The new one was installed in late 2021. In the spring, I noticed it was getting hot upstairs. Recently we had several days in the high nineties and I could not sleep at night as it was so hot. The HVAC company sent out a technician who services and cleaned Air Conditioner outside as well as giving me a new filter.

As I was so desperate, I had bought window fans, tower fans and a Black and Decker portable air conditioner. I installed the portable air conditioner in the window after having to saw the slider. It may work but it is too noisy and I cannot sleep. As an interim solution, I reconverted a study downstairs and sleep quite comfortably there on the new bed I purchased.

The HVAC guy recommended that I get the insulation blown in insulation for the attic. A company is coming to remove the old batt, install new and spray foam in the knee walls next week. This will cost slightly over $5,000. I do not think it will help sufficiently.

I really do not know what I am doing. I have been researching solutions. I do not like the window air conditioners, the portable window fan is too noisy. The window fan works quite well but sucks in humidity as well. I would appreciate any advice - probably I will have to sleep downstairs in summer and upstairs in winter. I read old Boglehead threads and I guess that I should have had a multi-split system installed. But I have recently spent about $16,000 already and the house will likely to torn down when I move in a few years.

Thanks,

Lyntee

[SmallSaver]

There could be lots of things going on and many solutions. Attic insulation, attic ventilation, a mini-split for the upstairs...Best bet would be to find a company like this to take a look. Houses really need to be assessed comprehensively by someone who understands building performance. If you're not near Detroit, I'd still give those folks a all and see if they know anyone.

[delamer]

What was your upstairs like, cooling-wise, with your previous system?

[jebmke]

There could be lots of things going on and many solutions. Attic insulation, attic ventilation, a mini-split for the upstairs...Best bet would be to find a company like this to take a look. Houses really need to be assessed comprehensively by someone who understands building performance. If you're not near Detroit, I'd still give those folks a all and see if they know anyone.

agree; energy audit will find the leaks. Insulation can be important but so can sealing certain parts of the attic and upgrading windows. The audit will find the most vulnerable spots. In our case it was the hatch to the attic space, the plates and down lighting.

Some local electric companies will do these audits for free but it needs to include a full house blower test.

[Lynette]

What was your upstairs like, cooling-wise, with your previous system?

I have been in this house for nearly 30 years so this is my third HVAC. With the first one, I slept downstairs as the solo owner could not do anything. The second and third were installed by this reputable HVAC Company. With the second one I slept upstairs and did not notice the heat too much. The latest HVAC is really quiet and cools downstairs well. I was told that by he manager who sold me the new HVAC, that I did not need such a powerful one as the newer technology had improved the systems. The only think I can think is that it is not powerful enough to blow the cool air upstairs. I have been noticing that in my neighborhood most of the bungalows have window air conditioners upstairs.

[random_walker_77]

Cooling is about making sure that heat is removed faster than it comes in.

Heat comes in through the window, through the air gaps on the sides, and through the walls and attic. Insulation helps. Also, there are window films that reduce how much heat comes through the windows. Inexpensive v-seal can stop air leaks from the sides/bottom of windows.

For removing heat, does the duct bring in enough volume of cool air? Would adding an extra air-return force more cool air to the room?

For supplemental cooling, there are newer U-shaped inverter-based window air conditioners that are much quieter (i.e supposedly more like a refrigerator) and also very efficient. The nyt just reviewed some and named the Midea the best: https://www.nytimes.com/wirecutter/revi ... nditioner/
The reviews on amazon are pretty good. These U-shaped ones also allow you to continue using your window.

You could also consider a permanently installed mini-split system. Some also function as heaters in the winter, so long as it's not too cold outside. Example on slickdeals, but most people will need to get a a/c company to install it.

[Quercus Palustris]

Dumb question, but have you tried closing some/all of the downstairs supply registers? We have to do that in our house (2-story 1950s colonial; half baked duct layout) in the summer. It helps immensely -- even with downstairs vents mostly closed, enough air leaks out that it's chilly, while forcing more through the upstairs vents. We also upgraded our thermostat to an ecobee to have sensors upstairs in the rooms we're using / sleeping in.

[ZMonet]

As others have said, you really need a comprehensive assessment and the solution will likely be multi-faceted. One issue may be that the thermostat is downstairs and the new HVAC efficiently cools the downstairs to the set temperature, while the upstairs remains wamr. Have you taken a temperature reading in your bedroom? What is the difference in temp between that reading and your thermostat setting? One potential solution would be to add additional vents upstairs. Also, a new smart thermostat, like the Ecobee, would allow you to put temperature sensors throughout the house to try and get some sort of balance that works for you.

Again, the first step though is to get an assessment from someone that knows what they are doing. Clearly the reputable place does not as spending that much without an explanation of the limitations is not acceptable.

[adamthesmythe]

Hot air rises. So there is a tendency for upper floors to be warmer. To reduce this effect your options are

1. Rebalance air flow for more air flow to the upper floors.
2. More insulation, especially upper floors and attic.
3. Supplementary cooling (additional AC unit, minisplit, window AC...).

Absent some really elaborate calculations, you (and/or your contractor) will need to address this empirically, with choices based on prior experience.

I would do cheaper things first. Based on your posting, it appears you are floundering (and doing so in an expensive manner).

I had a much older house and the upstairs was always warmer. In my case the temperature difference was acceptable after minor fixes (mostly a bit more insulation in the attic).

[Lynette]

There could be lots of things going on and many solutions. Attic insulation, attic ventilation, a mini-split for the upstairs...Best bet would be to find a company like this to take a look. Houses really need to be assessed comprehensively by someone who understands building performance. If you're not near Detroit, I'd still give those folks a all and see if they know anyone.

agree; energy audit will find the leaks. Insulation can be important but so can sealing certain parts of the attic and upgrading windows. The audit will find the most vulnerable spots. In our case it was the hatch to the attic space, the plates and down lighting.

Some local electric companies will do these audits for free but it needs to include a full house blower test.

Thanks, this is worth considering. I had all of the windows replaced in my house about 15 years ago.

[Watty]

The first thing I would do is to get a thermometer and measure the air temperature of the air that is coming out of the vents when the AC is running. If that is not as cold as the downstairs vents then you know that you have a problem with getting cold air upstairs. Check all the vents in your house to see what the temperature of the air is since that may give you a clue about what is going on.

You may also want to get an inexpensive anemometer like this one to measure the airflow at each of the air vents.
https://www.amazon.com/Anemometer-Veloc ... C81&sr=8-5

Sometimes you can tune the ductwork to direct air to where it is needed most. Some ductwork will actually have levers inside the duct work in the basement to control this or you may have levers on each register to open and close them some. Be sure to not close down(or partially close down) too many registers since you can damage your system by restricting the airflow too much.

The next thing I would look at is if you have an adequate air return on the second floor to suck the warm upstairs air down to the AC and recirculate it.

There should be a vent that is in or near the ceiling on the top floor. When the AC is running you should be able to put your hand near it and feel the air going into the vent.

A 1950s house would likely not have had AC when it was built so this should have been added when AC was added to the house. It could have been added incorrectly or it could have become blocked over the years. It is also possible that when they added AC that they just did not add any air return especially if the house did not originally have ductwork for central heating.

If you have ductwork in the attic or basement it is also possible that one of those may have come loose or been damaged. If your cold air ductwork goes through the attic and it is not insulated then it could be that the attic is so hot in the summer that the air is being warmed up before it can get to the upstairs room. I once had a flexible duct in a crawlspace that had come loose which caused the air to go into the crawlspace instead of the house.

Something else to consider is if your thermostat is in a location downstairs where cold air may be blowing on it and turning off the AC before the upstairs is cool. This is less of a problem with heating since hot air rises and will warm up the upstairs.

Your HVAC company should have looked for these things but often they do not really want to get involved with anything other than the HVAC hardware.

[Watty]

One more thought. One thing to notice is if on a hot day your AC is running constantly or turning off and on as the thermostat says the temperature is right.

If it is not running constantly when the upstairs is too hot that tell you that you have a problem with getting the cool air to the right place. If that is the case then doing things like adding insulation might save you money but it might not solve the problem.

[Lynette]

Cooling is about making sure that heat is removed faster than it comes in.

Heat comes in through the window, through the air gaps on the sides, and through the walls and attic. Insulation helps. Also, there are window films that reduce how much heat comes through the windows. Inexpensive v-seal can stop air leaks from the sides/bottom of windows.

For removing heat, does the duct bring in enough volume of cool air? Would adding an extra air-return force more cool air to the room?

For supplemental cooling, there are newer U-shaped inverter-based window air conditioners that are much quieter (i.e supposedly more like a refrigerator) and also very efficient. The nyt just reviewed some and named the Midea the best: https://www.nytimes.com/wirecutter/revi ... nditioner/
The reviews on amazon are pretty good. These U-shaped ones also allow you to continue using your window.

You could also consider a permanently installed mini-split system. Some also function as heaters in the winter, so long as it's not too cold outside. Example on slickdeals, but most people will need to get a a/c company to install it.

Lol - thanks. You have no idea how much time I have spent on these reviews. I have a 8000 BTU Black and Decker Portable unit installed. I had to pray I would not cut off my hand when I cut off the slider so that it would fit the window. I also considered the DREO Twin Cool Portable Air conditioner. It seems that they cool better if they have dual hoses. Another problem is that the window is upstairs. I managed to carry the Black and Decker upstairs. It weighs 50lb. The other ones recommended that are 1200 BTUs weigh over 70lbs. I cannot carry them upstairs myself. I was thinking of ordering the DREO one and asking the Insulation guys to carry it upstairs for me on Monday. But that is just spending money without knowing it will work.

I have spent about $4000 for a new bed and furniture for the downstairs study I converted into a bedroom.

[Bud]

I have a similar situation, my air was 38 degrees coming out of the vents, the HVAC was brand new...

There are three solutions I came up with:

1) buy a mini-split unit for upstairs - very economical, initial cost and install can be about $3k to $5k (depending on unit and installer). This will definitely resolve your issue.
2) Install a second thermostat upstairs. This means your a/c turns off only when both your thermostats register the desired temperature. This will also resolve your issue but your downstairs will probably be about 8-10 degrees cooler than your upstairs.
3) use fans to suck cool air from downstairs into the upstairs. This is the low tech, low cost solution. This is the solution I use - my upstairs has an open railing to the downstairs and with one or two fans running, the upstairs cools well.

All the best.

[jebmke]

The next thing I would look at is if you have an adequate air return on the second floor to suck the warm upstairs air down to the AC and recirculate it.

There should be a vent that is in or near the ceiling on the top floor. When the AC is running you should be able to put your hand near it and feel the air going into the vent.

It isn't uncommon for small houses to be expanded by adding living space up without adding the proper return air ducting.

[Lynette]

The first thing I would do is to get a thermometer and measure the air temperature of the air that is coming out of the vents when the AC is running. If that is not as cold as the downstairs vents then you know that you have a problem with getting cold air upstairs. Check all the vents in your house to see what the temperature of the air is since that may give you a clue about what is going on.

You may also want to get an inexpensive anemometer like this one to measure the airflow at each of the air vents.
https://www.amazon.com/Anemometer-Veloc ... C81&sr=8-5

Sometimes you can tune the ductwork to direct air to where it is needed most. Some ductwork will actually have levers inside the duct work in the basement to control this or you may have levers on each register to open and close them some. Be sure to not close down(or partially close down) too many registers since you can damage your system by restricting the airflow too much.

The next thing I would look at is if you have an adequate air return on the second floor to suck the warm upstairs air down to the AC and recirculate it.

There should be a vent that is in or near the ceiling on the top floor. When the AC is running you should be able to put your hand near it and feel the air going into the vent.

A 1950s house would likely not have had AC when it was built so this should have been added when AC was added to the house. It could have been added incorrectly or it could have become blocked over the years. It is also possible that when they added AC that they just did not add any air return especially if the house did not originally have ductwork for central heating.

If you have ductwork in the attic or basement it is also possible that one of those may have come loose or been damaged. If your cold air ductwork goes through the attic and it is not insulated then it could be that the attic is so hot in the summer that the air is being warmed up before it can get to the upstairs room. I once had a flexible duct in a crawlspace that had come loose which caused the air to go into the crawlspace instead of the house.

Something else to consider is if your thermostat is in a location downstairs where cold air may be blowing on it and turning off the AC before the upstairs is cool. This is less of a problem with heating since hot air rises and will warm up the upstairs.

Your HVAC company should have looked for these things but often they do not really want to get involved with anything other than the HVAC hardware.

Thanks Watty. I appreciate all the advice you give on Bogleheads. I have six themometers stationed all around my house and I am measuring the heat and humidity in various locations on different days. The HVAC guy noticed that I had a bed in front of one of the intake vents. I moved the bed but it did not make much difference. He also put his hand in front of the vent and mentioned that the flow was not very strong. So it may be that either the new HVAC is under powered or the pipes are leaking.

Recently there was a 8 degree difference between upstairs and downstairs. I have the thermostat downstairs set to 72 degrees and some days this is to cold for me. At the moment I am sitting with a blanket over my knees.

I guess the solution is to call in an expert to analyse the whole house. But as I have likely spent nearly $20,000, I am not sure it is worth spending much more as I can sleep downstairs in summer. Incidentally I bought a new bed and the guys from the furniture store delivered it at 12:30 am the same day.

I have just seen your response. The space upstairs was not expanded. Downstairs there is an addition without ducting but it is only four degrees warmer. That is OK for me.

Sorry I see that you mention a device to measure the airflow. The HVAC already noticed that the airflow upstairs was not really strong. I guess that as some mentioned I need to call in a professional to analyze the situation - after I get my new $5000 insulation on Monday. The sales rep told me he was offering me the "economical' solution. I guess his expensive solution is likely $20,000. This is only insulation and does not address leaky pipes.

Thanks all. I will wait until after the new insulation is installed on Monday. We are supposed to have some days in the nineties next week.

Thanks,

Lynette

[Malum Prohibitum]

I have long been of the opinion that a 2 story house must have two separate units, one for upstairs, and one for downstairs.

[like2read]

Here is a simple thing that hasn't been mentioned yet. The fan setting on your thermostat, is it set to "auto" or "on" during the summer? Years ago we learned to switch it to on May through September. Cold air sinks. Our basement is always much cooler during the summer. Air intakes on lower level(s) will take in that colder air and circulate it throughout the house. Significant and noticeable improvement.

l2r

[tibbitts]

I don't think windows are the problem. Windows installed 15yrs ago would surely have been Low-E and while some of the gas might have leaked out that gas is what, maybe half an R-value?

It sounds like you downsized the air conditioner? If so that could be a problem. Air conditioners have gotten more efficient but I'm not aware that they've become magically more effective per btu or per ton. On the other hand they've been somewhat unpredictable in my experience. I went from 2.5T (1-stage) to 3T (2-stage) and it seemed like that 3T provided more like 2T of cooling (and yes the 2nd stage was confirmed to be working.) Now I have a 3.5T 1-stage and so far it feels more like at least a 4T vs. the 3T.

[like2read]

Other relatively inexpensive thing to do is add ceiling fans in upstairs bedrooms. Big help.

l2r

[jb3]

Had similar problem. We got a Midea U-Shaped window ac. It is very efficient and quiet because the compressor sits outside.

It's kind of like a "mini" mini-split. Cost us around $350. Works well to help cool our top floor, as an adjunct to central ac.

[fposte]

I have a 1940s Cape Cod style in the Midwest; I suspect bungalows and Cape Cods have similar second floor issues, since they're both very close, sometimes directly under, the roof. My differentiation isn't as bad as yours, but could be as much as 5 degrees.

I had an energy audit and some additional insulation has been added, though I suspect given they were mostly band joists and one gable wall that it's more significant in the winter. I keep blinds and shades closed upstairs in the summer. The bedroom I use has honeycomb blinds in a cream color, so some light comes in but it blocks a lot of heat. I keep the first floor registers closed in summer. I run the ceiling fan every night. I at one point considered an upstairs dehumidifier but the humidity upstairs is fine. Ultimately, though, I accept that downstairs is going to be overcooled at night and set the nighttime temp according to upstairs comfort, not the actual thermostat number downstairs.

When I had back issues and slept on the floor for awhile, it was brilliant--the register is close to floor level so I really got the benefit, and I was directly under the ceiling fan. That may be a bit drastic for you, but anything you can do to get closer to the outflow and moving air is probably good. You might also look into something like the bed fan to get maximum cooling value from moving air.

[psteinx]

We have a 2 story house (+ finished basement, so effectively ~3 story) that we service with a single HVAC unit. In St. Louis area - HOT summers, cold winters.

Thoughts/observations/suggestions:

1) You were OK with HVAC 2 but are now unhappy with HVAC 3. But you are pursuing a lot of expensive solutions (moving downstairs with new furniture, blown in insulation) without really considering what might have changed between 2 and 3. There are various possibilities:
A) 2 was much more powerful, and kept the downstairs AND upstairs several degrees colder
B) It's ~psychosomatic - the upstairs was the same temperature under 2 and 3, but the replacement of the HVAC made you more sensitized/aware of the temperature
C) The thermostat settings changed, either by the installer, or by you. For instance, the fan used to run all the time (even with the cooling not engaged) and now it doesn't.
D) The air handling changed. The basic cooling is comparable (i.e. downstairs) but the fan strength is weaker. Note that in an attempt to be more energy efficient, newer HVACs try to be smarter about fan usage, but this may be a in way detrimental to air flow for a house that was marginal before

So, before you look OUTSIDE of the HVAC system for solutions, I would investigate the above. The HVAC company's initial response (cleaning the outside air unit and putting in a new filter) seems almost laughable. You might start with getting the HVAC company to send a new tech, who can talk you through thermostat settings and obvious airflow issues driven from the unit side (rather than your house's design)

2) Vent and return management can be a big issue. Make sure the upstairs vents - both those pushing air OUT and those returning air IN are unimpeded - not blocked by beds or furniture, AND that the registers are fully open. Then, experiment with reducing airflow downstairs to push more of the flow upstairs. You probably don't want to completely cut off downstairs airflow though. (That said, typical registers don't completely cut off airflow anyways).

3) If there are windows upstairs getting a lot of sunlight, and especially if those windows are in rooms/places seldom used, consider blinds/drapes, and/or use the ones you have.

4) Generally, keep doors open for airflow. If there's a TRULY unused room or two in the house, you could "cut it off" by closing the door and registers inside.

5) Be aware of possible airflow leaks, especially as this seems to be an old house.

6) Consider adding an extra vent upstairs in your bedroom, possibly fed by new ducting, or just tapping into existing ducting. I spend much of my time in a large-ish room on the 2nd floor of my house that was being inadequately cooled by the single vent. I had an HVAC company run an extra vent to the room (required ductwork through the kitchen pantry on the main floor - not ideal, but...) and it was highly effective.

7) Consider a smart thermostat (or use the settings of your current thermostat, if it has them), to crank the overall temperature DOWN in the evening (and UP somewhat during the day). If you spend your evenings mostly upstairs, and days mostly downstairs, and the house is ~6-8 degrees cooler downstairs than up (not entirely atypical), then you may want the evening temperature 3-5 degrees cooler than the daytime temperature (comfortable sleeping temp may be a little higher than comfortable daytime temp). Is this a little inefficent? Sure, but it probably doesn't make THAT much difference to your electric bill, and evenings tend to be cooler than days anyways, and you're probably only dealing with the hottest 90+ degree days for ~2-3 months/year.

===

In general, there are a lot of free/cheap solutions I'd try before sinking thousands into more insulation and more furniture, or even hundreds into more window A/C units (those have their own issues - noisy and interfere with window function). It's possible that YES, you do need more insulation, but I wouldn't jump to that conclusion quickly.

[psteinx]

Other relatively inexpensive thing to do is add ceiling fans in upstairs bedrooms. Big help.

l2r

Good idea.

[Watty]

The HVAC guy noticed that I had a bed in front of one of the intake vents.

Intake vents should be near the ceiling so they will get hot air. In that room you might want to measure the temperature at the floor level and ceiling level to see if there is much difference.

He also put his hand in front of the vent and mentioned that the flow was not very strong.

That is a problem that should be looked into.

[psteinx]

The HVAC guy noticed that I had a bed in front of one of the intake vents.

Intake vents should be near the ceiling so they will get hot air. In that room you might want to measure the temperature at the floor level and ceiling level to see if there is much difference.

I'm guessing either the installer said it was an OUT vent and the OP misheard, or the OP is just fumbling the word choice here on this forum.

I know the phrase "intake vent", but I'm not even sure of the correct term for a vent that does the opposite. (I think most folks just call it an unspecific "vent").

[Valuethinker]

I would appreciate advice on how to cool the upstairs of my house in Michigan. It is a 1400 sq foot bungalow that was built in 1950. Probably 60% of the small houses like mine in my neighborhood have been torn down and replaced by houses costing from $1 to 1.5 million.

I had a new Bryant furnace and air- conditioner installed in September 2021 by a reputable local HVAC company. It cost about $10,000 with rebates for being energy efficient. I had problems with the heat upstairs with my first HVAC, the second one seemed OK. The new one was installed in late 2021. In the spring, I noticed it was getting hot upstairs. Recently we had several days in the high nineties and I could not sleep at night as it was so hot. The HVAC company sent out a technician who services and cleaned Air Conditioner outside as well as giving me a new filter.

As I was so desperate, I had bought window fans, tower fans and a Black and Decker portable air conditioner. I installed the portable air conditioner in the window after having to saw the slider. It may work but it is too noisy and I cannot sleep. As an interim solution, I reconverted a study downstairs and sleep quite comfortably there on the new bed I purchased.

The HVAC guy recommended that I get the insulation blown in insulation for the attic. A company is coming to remove the old batt, install new and spray foam in the knee walls next week. This will cost slightly over $5,000. I do not think it will help sufficiently.

I really do not know what I am doing. I have been researching solutions. I do not like the window air conditioners, the portable window fan is too noisy. The window fan works quite well but sucks in humidity as well. I would appreciate any advice - probably I will have to sleep downstairs in summer and upstairs in winter. I read old Boglehead threads and I guess that I should have had a multi-split system installed. But I have recently spent about $16,000 already and the house will likely to torn down when I move in a few years.

Thanks,

Lyntee

Drawing together all of the suggestions:

1. get an energy audit done. Without that you could miss the real cause of the situation

2. it may/ may not be feasible to address problem with insulation and air tightness. But probably no solution will work without having done the minimum at least of that.

3. this problem screams "mini split" upstairs. Which can also be a very efficient solution. Put it on a few hours before you go to bed (hence point 2).

So 1 & possibly 2 come first. Then mini split.

[jayjayc]

My guess is that your attic is acting like an oven. Take the temperature in the attic around 5pm and see how hot it is. The sun bakes the attic and it retains heat into the evening and night. I'd call a roofing company to assess it and see what's best for you. One good solution is to install ridge vents. They're installed on the very top of your roof and allow hot air to escape.

Your A/C may be working fine. It just can't out-compete the heat in the attic.

[Mister Whale]

Good article in Fine Homebuilding about the technical aspects of insulating attic space with knee walls:

https://www.finehomebuilding.com/2012/0 ... -kneewalls

If you currently have old batt insulation in the knee walls, spray foam (or some other approach to insulating and air-sealing) will make a big difference.

I would also want to conduct an energy audit to see how much heat load is being transferred to the living space, and a Manual J calculation done to correctly size the cooling load necessary.

[Mr. Rumples]

One overlooked consideration is clothing and bedding. Wear all cotton clothing, not blends and have sheets and throws that are all cotton. Better yet, but not as common, is to have the sheets made out of true linen (which comes from flax). Linen sheets are not inexpensive, but a good night's sleep is priceless.

When I replace my attic insulation I might add reflective foil insulation between the rafters. I have more research to do on this, might be overkill, but perhaps not since the air handling unit is up there.

Regarding ridge vents, I had them put in when I had my roof replaced. I wish I had had something with a power fan, either solar or electric.

Note about insulation. There is some debate where I live about insulating walls on older homes. Some "experts" say not to, others say to. In short, these homes were built to "breathe." As I said, there is debate. I have thus decided to be cautious and won't. An insulation "expert" should know about older homes.

If there are any museum houses nearby contact them, or contact your local historic preservation society, local historic commission or state preservation society. For more about energy and older homes:

https://archive.epa.gov/region5/sustain ... -homes.pdf

Many of today's trained folks simply don't know about older homes. A quick search shows MI has older home experts.

[Lynette]

Here is a simple thing that hasn't been mentioned yet. The fan setting on your thermostat, is it set to "auto" or "on" during the summer? Years ago we learned to switch it to on May through September. Cold air sinks. Our basement is always much cooler during the summer. Air intakes on lower level(s) will take in that colder air and circulate it throughout the house. Significant and noticeable improvement.

l2r

Yes, thanks - HVAC guy told me to put it onto ON. So that has not helped much.

[delamer]

What was your upstairs like, cooling-wise, with your previous system?

I have been in this house for nearly 30 years so this is my third HVAC. With the first one, I slept downstairs as the solo owner could not do anything. The second and third were installed by this reputable HVAC Company. With the second one I slept upstairs and did not notice the heat too much. The latest HVAC is really quiet and cools downstairs well. I was told that by he manager who sold me the new HVAC, that I did not need such a powerful one as the newer technology had improved the systems. The only think I can think is that it is not powerful enough to blow the cool air upstairs. I have been noticing that in my neighborhood most of the bungalows have window air conditioners upstairs.

If the old unit supplied the necessary coolness upstairs, then the new unit isn’t up to snuff. All the other suggestions — like adjusting the vents or keeping the fan on —may be helpful at the margins, but they aren’t going to solve the problem.

So the HVAC company sold you a unit that doesn’t fit your needs.

Have you considered having another contractor come in amd evaluate the system you were sold? Or maybe arranging to have a rep from the manufacturer come out for the same purpose?

[Lynette]

Other relatively inexpensive thing to do is add ceiling fans in upstairs bedrooms. Big help.

l2r

Thanks - Yes I have a ceiling fan - its great for making me feel cool. However, it does not actually lower the termperature.

[Lynette]

I don't think windows are the problem. Windows installed 15yrs ago would surely have been Low-E and while some of the gas might have leaked out that gas is what, maybe half an R-value?

It sounds like you downsized the air conditioner? If so that could be a problem. Air conditioners have gotten more efficient but I'm not aware that they've become magically more effective per btu or per ton. On the other hand they've been somewhat unpredictable in my experience. I went from 2.5T (1-stage) to 3T (2-stage) and it seemed like that 3T provided more like 2T of cooling (and yes the 2nd stage was confirmed to be working.) Now I have a 3.5T 1-stage and so far it feels more like at least a 4T vs. the 3T.

Either the air conditioner or furnace. I did this on advice of the HVAC guy. I am sorry I did but this was installed in September 2021 and I cannot go back. The

[CC1E]

Many HVAC “professionals” just eyeball things and rely on past experience. They don’t actually run the calculations required to size and properly install systems. In the case of old houses with poor supply/return ductwork this is what happens.

I would install mini split unit(s) for the bedroom(s) upstairs. They’re the best way to get cooling where it’s needed.

[orange96]

Use a fan at the bottom of the stairs to move air to the second floor.

[Walkure]

The HVAC guy noticed that I had a bed in front of one of the intake vents.

Intake vents should be near the ceiling so they will get hot air. In that room you might want to measure the temperature at the floor level and ceiling level to see if there is much difference.

I'm guessing either the installer said it was an OUT vent and the OP misheard, or the OP is just fumbling the word choice here on this forum.

I know the phrase "intake vent", but I'm not even sure of the correct term for a vent that does the opposite. (I think most folks just call it an unspecific "vent").

All of these things fall under the category of what an HVAC engineer would call "Air Terminals," e.g. where the ductwork terminates in a space. Air flowing into the room is called "supply," air being drawn out the room is called "return."

A very handy summary from the Lowe's website:

Grilles and Vents
The difference between a vent or register and a grille is that registers often have dampers, or louvers, that allow you to control the airflow by opening or closing the vent. Grilles don’t come in these louvered styles and are typically used in homes with central heating and cooling units for removing air and returning it to a heating, ventilating and air conditioning system. A return air vent also extracts air from a room and recycles it, rather than pushing it out into the space. These are typically installed in hallways or ceilings and don’t have a damper.

Floor Vents
Floor vents or registers are ideal if you live in a climate where heating your home is your primary concern. Since warm air rises, the heat that comes out of your floor vents will warm your room as it ascends. These types of vents are typically placed near windows so the warm air from the ducts and the cooler air coming from the window can mix.

You’ll want to ensure that your floor vents aren’t obstructed so as not to interrupt the airflow, so consider choosing decorative vent covers that’ll complement the décor of your room. Consider vents in scroll or wicker patterns that are both visually appealing and functional. If you want your vents to truly blend in with wood floors or paneling, filter a search by wood vent covers on Lowes.com.

Sidewall and Ceiling Registers
Ceiling registers are ideal for warm climates, where you’re more focused on cooling your home. The placement of sidewall and ceiling registers helps to circulate air, as the register will draw warm air up to it. The grilles or vent covers used on these types of registers are typically thinner, as they don’t need to withstand foot traffic like floor vents do, and registers on ceilings and sidewalls will generally be more visible in a room. Depending on the size and shape of your room and the placement of the vent itself, you may need either a two-way or a three-way register that sends air out in several directions at once.

Diffusers
If you’re looking for a way to push air into all parts of a room, a baseboard diffuser or ceiling diffuser may be more useful than a register. Though you can open and close registers with louvers, the direction in which a register will distribute air is fixed to one, two or three directions. A diffuser sends air out into your room in all directions, helping to heat or cool it more uniformly.

Boosters
If your vents alone aren’t heating or cooling your home as efficiently as you’d like, consider the addition of a register booster. Also called an in-floor booster or register fan, this option consists of a small fan that sits in or on registers in rooms where the airflow is suboptimal.

[tibbitts]

I don't think windows are the problem. Windows installed 15yrs ago would surely have been Low-E and while some of the gas might have leaked out that gas is what, maybe half an R-value?

It sounds like you downsized the air conditioner? If so that could be a problem. Air conditioners have gotten more efficient but I'm not aware that they've become magically more effective per btu or per ton. On the other hand they've been somewhat unpredictable in my experience. I went from 2.5T (1-stage) to 3T (2-stage) and it seemed like that 3T provided more like 2T of cooling (and yes the 2nd stage was confirmed to be working.) Now I have a 3.5T 1-stage and so far it feels more like at least a 4T vs. the 3T.

Either the air conditioner or furnace. I did this on advice of the HVAC guy. I am sorry I did but this was installed in September 2021 and I cannot go back. The

It doesn't seem typical for an hvac person to recommend a smaller unit, because ultimately people will almost never complain if they are at least as hot/cold as they want to be. Humidity might be a factor in a few cases with overcapacity on the cooling side. An exception during this pandemic era would be if they could obtain a smaller unit but not a larger one.

[Johnny Thinwallet]

Our house was built in 2005 so this may or may not be pertinent to your situation with an older house, but we previously had issues cooling the upstairs bedrooms.

What solved the problem for us was addressing our attic insulation this past spring. Now this summer our 2nd story actually runs slightly cooler than our main level even during hot summer days (and we've had several days with heat indexes at 100-105 so far this year). Each evening it's cool and comfortable for sleeping. And our AC is running less and we're saving $$ on electricity too.

Prior to the insulation, we had R30 (at best) with tons of air leaks and areas with far less than R30. Now we're R60, air gaps are sealed and a knee wall was reinforced with a radiant barrier. It's been a game-changer in comfort for us this summer. I did the project primarily for comfort, and the energy savings has been a bonus.

[dboeger1]

I have long been of the opinion that a 2 story house must have two separate units, one for upstairs, and one for downstairs.

Admittedly, I am not very knowledgable about HVAC, but this just makes sense to me. I mean, when you go to Asia and see these huge high rises with mini-splits in all of the units and people just setting whatever independent temperature they want in their own rooms, it makes perfect sense. We have 2 mini-split systems in our house now, a 3-zone for the bedrooms and a separate 1-zone for the larger kitchen/living room area, and they work wonderfully. We never cool or heat the whole house, just whichever room(s) we're in at the time. I'm not sure it's strictly more efficient on a per-sqft basis just because there's obviously much more leakage between indoor rooms, but you're heating/cooling way fewer sqft, so I can't imagine it's as expensive overall, and it's great not having to worry about air flow through the ducts. It's all ductless, so the cooling goes directly where it's needed.

[MathWizard]

Likely you have a single zone, and the thermostat is downstairs.

Getting the system balanced is best, but having a separate zone upstairs
with its own thermostat would help. The solution of a mini-split for the
upstairs would do that, but proper duct sizing and perhaps automated
dampers may do this as well.

Automated dampers and booster fans are old school, but so is your house.
I used a booster to get extra warm air into a large addition built well after the
HVAC was put in. Not ideal, but a cheap solution.

The simplest may just be in inline booster to get more air to the 2nd floor.
You could use a timer so that it only runs during the evening and night, or just let it run all day
until you get the problem corrected.

Not a recommendation, but these are what I am describing:
https://suncourt.com/collections/automa ... ol-dampers

[windaar]

Here is a simple thing that hasn't been mentioned yet. The fan setting on your thermostat, is it set to "auto" or "on" during the summer? Years ago we learned to switch it to on May through September. Cold air sinks. Our basement is always much cooler during the summer. Air intakes on lower level(s) will take in that colder air and circulate it throughout the house. Significant and noticeable improvement.

l2r

Yes, thanks - HVAC guy told me to put it onto ON. So that has not helped much.

Beware that in most situations leaving the AC permanently blowing ("on") greatly decreases dehumidification, which relies on cycles for the moisture to condense and run off of the coils when not blowing.

[Finnegan]

Second the recommendation for a zone valve in the ducting and a second thermostat for upstairs. That fixed the problem I had in my two story townhouse.

[59Gibson]

Attic fan has helped me with a similar style and age house. Its consistency 2 degrees cooler upstairs than 1st floor, even when near 100 degrees outside. I'm not saying it's the only answer, but it's a fairly inexpensive piece of the solution.

[Harry Livermore]

Dumb question, but have you tried closing some/all of the downstairs supply registers? We have to do that in our house (2-story 1950s colonial; half baked duct layout) in the summer. It helps immensely -- even with downstairs vents mostly closed, enough air leaks out that it's chilly, while forcing more through the upstairs vents. We also upgraded our thermostat to an ecobee to have sensors upstairs in the rooms we're using / sleeping in.

Was going to suggest this too. It may be that you just need to "balance" the air flow between the upstairs (which clearly needs more) and the downstairs (which might be adequate or even over-cooled)
Where is the thermostat located? My opinion is that it should be where the cooling is needed more (usually upstairs)
Cheers

[Lynette]

The HVAC guy noticed that I had a bed in front of one of the intake vents.

Intake vents should be near the ceiling so they will get hot air. In that room you might want to measure the temperature at the floor level and ceiling level to see if there is much difference.

I'm guessing either the installer said it was an OUT vent and the OP misheard, or the OP is just fumbling the word choice here on this forum.

I know the phrase "intake vent", but I'm not even sure of the correct term for a vent that does the opposite. (I think most folks just call it an unspecific "vent").

All of these things fall under the category of what an HVAC engineer would call "Air Terminals," e.g. where the ductwork terminates in a space. Air flowing into the room is called "supply," air being drawn out the room is called "return."

A very handy summary from the Lowe's website:

Grilles and Vents
The difference between a vent or register and a grille is that registers often have dampers, or louvers, that allow you to control the airflow by opening or closing the vent. Grilles don’t come in these louvered styles and are typically used in homes with central heating and cooling units for removing air and returning it to a heating, ventilating and air conditioning system. A return air vent also extracts air from a room and recycles it, rather than pushing it out into the space. These are typically installed in hallways or ceilings and don’t have a damper.

Floor Vents
Floor vents or registers are ideal if you live in a climate where heating your home is your primary concern. Since warm air rises, the heat that comes out of your floor vents will warm your room as it ascends. These types of vents are typically placed near windows so the warm air from the ducts and the cooler air coming from the window can mix.

You’ll want to ensure that your floor vents aren’t obstructed so as not to interrupt the airflow, so consider choosing decorative vent covers that’ll complement the décor of your room. Consider vents in scroll or wicker patterns that are both visually appealing and functional. If you want your vents to truly blend in with wood floors or paneling, filter a search by wood vent covers on Lowes.com.

Sidewall and Ceiling Registers
Ceiling registers are ideal for warm climates, where you’re more focused on cooling your home. The placement of sidewall and ceiling registers helps to circulate air, as the register will draw warm air up to it. The grilles or vent covers used on these types of registers are typically thinner, as they don’t need to withstand foot traffic like floor vents do, and registers on ceilings and sidewalls will generally be more visible in a room. Depending on the size and shape of your room and the placement of the vent itself, you may need either a two-way or a three-way register that sends air out in several directions at once.

Diffusers
If you’re looking for a way to push air into all parts of a room, a baseboard diffuser or ceiling diffuser may be more useful than a register. Though you can open and close registers with louvers, the direction in which a register will distribute air is fixed to one, two or three directions. A diffuser sends air out into your room in all directions, helping to heat or cool it more uniformly.

Boosters
If your vents alone aren’t heating or cooling your home as efficiently as you’d like, consider the addition of a register booster. Also called an in-floor booster or register fan, this option consists of a small fan that sits in or on registers in rooms where the airflow is suboptimal.

Lol - thanks. The "things" that have louvres and blow cold air into the room are on the baseboard. The "things" that don't have louvres are also on the baseboard. As I mentioned I live in Michigan and the main purpose is to heat the house in winter. When I purchased the house it did not have air-conditioning. The solo HVAC guy who installed it tried to install a booster in the basement to force air up into the ducts. It did not help.

[Lynette]

My guess is that your attic is acting like an oven. Take the temperature in the attic around 5pm and see how hot it is. The sun bakes the attic and it retains heat into the evening and night. I'd call a roofing company to assess it and see what's best for you. One good solution is to install ridge vents. They're installed on the very top of your roof and allow hot air to escape.

Your A/C may be working fine. It just can't out-compete the heat in the attic.

There is a window on top of the stairs that divide the attic. There are two hatches to access the access on both sides. I opened the hatches the other day and to look at the attic. It was boiling up there and there was a gap between the batt and the roof so that I could see the light. The Insulation company states the front of the house is 32 feet and the knee wall 6.5 ft. They are going to remove 352 sqft of batt and replace 416 R30 batt. They are going to 704 sqft with foam. For this I will pay $5,154.

I have also been reading that ridge vents are the best. I will consider this as a possible solution but I don't want leakage in my roof that I think is about ten years old.

Thanks!

Lynette

[Lynette]

I have long been of the opinion that a 2 story house must have two separate units, one for upstairs, and one for downstairs.

Admittedly, I am not very knowledgable about HVAC, but this just makes sense to me. I mean, when you go to Asia and see these huge high rises with mini-splits in all of the units and people just setting whatever independent temperature they want in their own rooms, it makes perfect sense. We have 2 mini-split systems in our house now, a 3-zone for the bedrooms and a separate 1-zone for the larger kitchen/living room area, and they work wonderfully. We never cool or heat the whole house, just whichever room(s) we're in at the time. I'm not sure it's strictly more efficient on a per-sqft basis just because there's obviously much more leakage between indoor rooms, but you're heating/cooling way fewer sqft, so I can't imagine it's as expensive overall, and it's great not having to worry about air flow through the ducts. It's all ductless, so the cooling goes directly where it's needed.

I think that this might be an ideal solution. Does anyone know if I can keep my present system and add a split system for upstairs? I assume that I would need to have an additional unit outside as well as running cables upstairs.

[Lynette]

What was your upstairs like, cooling-wise, with your previous system?

I have been in this house for nearly 30 years so this is my third HVAC. With the first one, I slept downstairs as the solo owner could not do anything. The second and third were installed by this reputable HVAC Company. With the second one I slept upstairs and did not notice the heat too much. The latest HVAC is really quiet and cools downstairs well. I was told that by he manager who sold me the new HVAC, that I did not need such a powerful one as the newer technology had improved the systems. The only think I can think is that it is not powerful enough to blow the cool air upstairs. I have been noticing that in my neighborhood most of the bungalows have window air conditioners upstairs.

If the old unit supplied the necessary coolness upstairs, then the new unit isn’t up to snuff. All the other suggestions — like adjusting the vents or keeping the fan on —may be helpful at the margins, but they aren’t going to solve the problem.

So the HVAC company sold you a unit that doesn’t fit your needs.

Have you considered having another contractor come in amd evaluate the system you were sold? Or maybe arranging to have a rep from the manufacturer come out for the same purpose?

The HVAC company guy ran various calculations and came up with the recommendation for the size of the HVAC. I asked the technician whether they would look at the duct work or consider alternatives. I think he was highly experienced but a little lazy. He mentioned that it might take several visits to diagnoze and repair the problem. I will wait until the insulation is installed and if it is not suitable, I will call the HVAC company again. I think they care as they have been in the business for a long time and have a good reputation. If this does not help, I will call an independent contractor to do an evaluation. Detroit Energy does a "free" audit.

I will see but in my neighborhood about 50% of the bungalows like mine see to have have window air conditioners,

Thanks,

Lynette

[indexfundfan]

Consider adding a register booster fan to boost the airflow to the room.

https://www.amazon.com/AC-Infinity-Regi ... B07T929DXL