If i turn off central AC will it damage drywalls?

Questions on how we spend our money and our time - consumer goods and services, home and vehicle, leisure and recreational activities
Post Reply
math22
Posts: 57
Joined: Wed Jan 13, 2016 8:11 pm
Location: USA

If i turn off central AC will it damage drywalls?

Post by math22 » Fri Jul 14, 2017 1:52 pm

I have heard from different people that we should keep our house (with central air) somewhat cool even when we are out of the house.
We live in a townhouse (3000 sqrft).

There are 2 situations that I am interested:

1. During the day while we are all out at work, temperature outside can reach 90-100 degrees during summer. Can I turn off the AC and turn it back on after I get home? Or will it somehow damage the house structure/drywalls?

2. During summer vacation, if I am out for lets say 3 weeks .Can I turn off the AC and turn it back on after I get home? Or will it somehow damage the house structure/drywalls?

Please Ignore how long the AC will take to cool the house down to the temperature that i like. The question is more if it will damage the house.

User avatar
dm200
Posts: 17780
Joined: Mon Feb 26, 2007 2:21 pm
Location: Washington DC area

Re: If i turn off central AC will it damage drywalls?

Post by dm200 » Fri Jul 14, 2017 1:55 pm

math22 wrote:I have heard from different people that we should keep our house (with central air) somewhat cool even when we are out of the house.
We live in a townhouse (3000 sqrft).
There are 2 situations that I am interested:
1. During the day while we are all out at work, temperature outside can reach 90-100 degrees during summer. Can I turn off the AC and turn it back on after I get home? Or will it somehow damage the house structure/drywalls?
2. During summer vacation, if I am out for lets say 3 weeks .Can I turn off the AC and turn it back on after I get home? Or will it somehow damage the house structure/drywalls?
Please Ignore how long the AC will take to cool the house down to the temperature that i like. The question is more if it will damage the house.
My guess is that high humidity might be potentially harmful.

jandres12
Posts: 6
Joined: Mon Apr 04, 2016 11:20 am

Re: If i turn off central AC will it damage drywalls?

Post by jandres12 » Fri Jul 14, 2017 1:57 pm

If you live in the South or in a humid climate, leave the AC on at a higher temperature. Otherwise you risk mold forming on your drywall and other parts of your house. I personally leave it at 82 during the day and when on vacation.

retiredjg
Posts: 33588
Joined: Thu Jan 10, 2008 12:56 pm

Re: If i turn off central AC will it damage drywalls?

Post by retiredjg » Fri Jul 14, 2017 1:59 pm

Where I live, turning it off will result in mildew. Even though I don't "need" a/c all the time, I make sure it runs at least some.

User avatar
TheAlaskan
Posts: 12
Joined: Sun Jun 11, 2017 7:31 am

Re: If i turn off central AC will it damage drywalls?

Post by TheAlaskan » Fri Jul 14, 2017 2:07 pm

You should leave it on to some high set point when you are away, maybe 85F. As you said, it's not so much a temperature issue, it is a humidity issue. You just want your AC to drop the humidity out of the air inside the house in order to prevent from creating an environment where mold/mildew can grow.

neilpilot
Posts: 1830
Joined: Fri Dec 04, 2015 1:46 pm
Location: Memphis area

Re: If i turn off central AC will it damage drywalls?

Post by neilpilot » Fri Jul 14, 2017 2:12 pm

Also, if you have any hardwood flooring it's susceptible to damage (warpage) from humidity.

runner3081
Posts: 1588
Joined: Mon Aug 22, 2016 3:22 pm

Re: If i turn off central AC will it damage drywalls?

Post by runner3081 » Fri Jul 14, 2017 3:30 pm

As others have mentioned, depends on the humidity.

As we speak, our house in the Phoenix area is sitting at 86 on the thermostat while we are on vacation. Have done this many times before with no issues at that temp.

We can't completely turn it off, the cats might be baked when we get home :)

User avatar
jharkin
Posts: 1781
Joined: Mon Mar 28, 2016 7:14 am
Location: Boston suburbs

Re: If i turn off central AC will it damage drywalls?

Post by jharkin » Fri Jul 14, 2017 3:36 pm

We need to know where you live. In New England where I am only newer construction homes even have central AC... And we do get into the 80s and occasionally 90s and humid in Summer.


The ultra humid deep south is another story, but remember that prior to the last 50 years people did live there... without any AC... and their houses didn't just collapse :)

retiredjg
Posts: 33588
Joined: Thu Jan 10, 2008 12:56 pm

Re: If i turn off central AC will it damage drywalls?

Post by retiredjg » Fri Jul 14, 2017 3:37 pm

jharkin wrote:The ultra humid deep south is another story, but remember that prior to the last 50 years people did live there... without any AC... and their houses didn't just collapse :)
Lived it! An attic fan is a wonderful thing. :happy

User avatar
jabberwockOG
Posts: 1395
Joined: Thu May 28, 2015 7:23 am

Re: If i turn off central AC will it damage drywalls?

Post by jabberwockOG » Fri Jul 14, 2017 3:37 pm

Big temperature changes in a house are not good for the structure or the trim, paint and caulk of your house. All materials will expand and shrink at different rates as temperature and humidity goes up or down. Same goes for furniture. Result is cracks and potential warping of materials. Leave HVAC on but set to slightly higher temp in summer (and slightly lower in winter) but nothing too extreme if you are going to be gone for a long period of time. So for example we leave AC at 82 instead of the normal setting of approx 76 if we are going to be gone for a few days or more.

why3not
Posts: 187
Joined: Wed Aug 10, 2016 12:07 pm

Re: If i turn off central AC will it damage drywalls?

Post by why3not » Fri Jul 14, 2017 4:00 pm

jabberwockOG wrote:Big temperature changes in a house are not good for the structure or the trim, paint and caulk of your house. All materials will expand and shrink at different rates as temperature and humidity goes up or down. Same goes for furniture. Result is cracks and potential warping of materials.
+1
I have an inlaw/guest suite with it's own AC system. It gets used a few times a year at best a week or so a time at best. AC doesn't get turned on except when guests are here. I live in hot & humid south. No mold issues in the last 5 years, but you bet the drywall seams, nail pops & caulked joints crack much, much more than the rest of the house. I can repair all that myself & do, but if I had to pay someone to do it I would guess I would still probably come out ahead by leaving the AC off for the most part.

Gill
Posts: 4596
Joined: Sun Mar 04, 2007 8:38 pm
Location: Florida

Re: If i turn off central AC will it damage drywalls?

Post by Gill » Fri Jul 14, 2017 4:06 pm

In Florida you wouldn't dare shut off your air conditioner in the summer.
Gill

carolinaman
Posts: 3208
Joined: Wed Dec 28, 2011 9:56 am
Location: North Carolina

Re: If i turn off central AC will it damage drywalls?

Post by carolinaman » Fri Jul 14, 2017 4:14 pm

jandres12 wrote:If you live in the South or in a humid climate, leave the AC on at a higher temperature. Otherwise you risk mold forming on your drywall and other parts of your house. I personally leave it at 82 during the day and when on vacation.
I agree. It is 94 degrees in NC today with high humidity which will likely continue into August. The lack of circulating air could create mold and mildew in these kinds of conditions.

User avatar
just frank
Posts: 1455
Joined: Sun Nov 02, 2014 4:13 pm
Location: Philly Metro

Re: If i turn off central AC will it damage drywalls?

Post by just frank » Fri Jul 14, 2017 4:32 pm

Don't worry about the daily cycle....the long run at the end of the work day will be more efficient and give better dehumidification overall...and you will save energy and $$.

AS for the vacation...get a wifi thermostat like the EcoBee3 lite. I did. I can set the setpoint wherever I want while I'm away, and see how the temp and the humidity evolve over time by logging in every few days for a minute or two. If the humidity gets higher than 60%, I run the AC for a awhile, then return it to a high setpoint. IF the weather is dryer, this never needs to be done. Also....if I had a (surprise) flood, I would see a spike in the humidity and could act on the info.

jebmke
Posts: 8286
Joined: Thu Apr 05, 2007 2:44 pm

Re: If i turn off central AC will it damage drywalls?

Post by jebmke » Fri Jul 14, 2017 4:46 pm

just frank wrote:Don't worry about the daily cycle....the long run at the end of the work day will be more efficient and give better dehumidification overall...and you will save energy and $$.

AS for the vacation...get a wifi thermostat like the EcoBee3 lite. I did. I can set the setpoint wherever I want while I'm away, and see how the temp and the humidity evolve over time by logging in every few days for a minute or two. If the humidity gets higher than 60%, I run the AC for a awhile, then return it to a high setpoint. IF the weather is dryer, this never needs to be done. Also....if I had a (surprise) flood, I would see a spike in the humidity and could act on the info.
I'm surprised that there isn't an automatic humidity set point. Our system will kick on a low level (first stage on compressor, low fan) if the humidity goes above a certain level whether the temp calls for cooling or not.
When you discover that you are riding a dead horse, the best strategy is to dismount.

sk2101
Posts: 182
Joined: Sun Jun 02, 2013 4:54 pm

Re: If i turn off central AC will it damage drywalls?

Post by sk2101 » Fri Jul 14, 2017 5:01 pm

math22 wrote:I have heard from different people that we should keep our house (with central air) somewhat cool even when we are out of the house.
We live in a townhouse (3000 sqrft).

There are 2 situations that I am interested:

1. During the day while we are all out at work, temperature outside can reach 90-100 degrees during summer. Can I turn off the AC and turn it back on after I get home? Or will it somehow damage the house structure/drywalls?

2. During summer vacation, if I am out for lets say 3 weeks .Can I turn off the AC and turn it back on after I get home? Or will it somehow damage the house structure/drywalls?

Please Ignore how long the AC will take to cool the house down to the temperature that i like. The question is more if it will damage the house.
In areas of high humidity YES. I live in Florida and we have detached guest quarters that are seldom used so I used to set the thermostat at 82. It was still not enough and we still had issue with mold getting into clothes that were in the closet. Then I put in a Nest Thermostat that monitors the humidity and has a function "Cool to Dry" and it will turn cooling whenever it detects that humidity is getting high. No more issues since then.

User avatar
MikeWillRetire
Posts: 312
Joined: Fri Jun 29, 2012 12:36 pm

Re: If i turn off central AC will it damage drywalls?

Post by MikeWillRetire » Fri Jul 14, 2017 7:42 pm

Gill wrote:In Florida you wouldn't dare shut off your air conditioner in the summer.
Gill
What do the poor people do?

rgs92
Posts: 2145
Joined: Mon Mar 02, 2009 8:00 pm

Re: If i turn off central AC will it damage drywalls?

Post by rgs92 » Fri Jul 14, 2017 8:12 pm

My central air is never set above 74 degrees (F). Normally it's at 72. I don't like to sweat. Nah, don't be cheap and turn if off when you're away. I would never abuse my house like that.

The Wizard
Posts: 12168
Joined: Tue Mar 23, 2010 1:45 pm
Location: Reading, MA

Re: If i turn off central AC will it damage drywalls?

Post by The Wizard » Fri Jul 14, 2017 9:59 pm

MikeWillRetire wrote:
Gill wrote:In Florida you wouldn't dare shut off your air conditioner in the summer.
Gill
What do the poor people do?
I'm guessing they have the equivalent of air conditioning food stamps in Florida...
Attempted new signature...

tibbitts
Posts: 7944
Joined: Tue Feb 27, 2007 6:50 pm

Re: If i turn off central AC will it damage drywalls?

Post by tibbitts » Sat Jul 15, 2017 12:06 am

rgs92 wrote:My central air is never set above 74 degrees (F). Normally it's at 72. I don't like to sweat. Nah, don't be cheap and turn if off when you're away. I would never abuse my house like that.
I leave my condo in FL at 77 when I'm gone, and here in OK at 78 during the day. But 78 at the thermostat here means 82-ish in the main living area, and probably 80 average around the house. In FL 77 is 77. FL is very cheap to cool and for $10 or whatever extra a month I think it might benefit some things like my old photos to be at a reasonable temperature. In Oklahoma any hotter and I'd never get the place cool at night - I need stage-2 running constantly after work to get the place comfortable for sleeping.

Goal33
Posts: 625
Joined: Sun Apr 12, 2015 12:30 pm

Re: If i turn off central AC will it damage drywalls?

Post by Goal33 » Sat Jul 15, 2017 12:09 am

I will start by saying I live in California and have basically no experience with humidity or temperatures managing to get above 80 degrees indoors.

I am just curious, if the concern of folks is humidity, what about a dehumidifier?... what am I missing?
A man with one watch always knows what time it is; a man with two watches is never sure.

The Wizard
Posts: 12168
Joined: Tue Mar 23, 2010 1:45 pm
Location: Reading, MA

Re: If i turn off central AC will it damage drywalls?

Post by The Wizard » Sat Jul 15, 2017 1:04 am

tibbitts wrote:
rgs92 wrote:My central air is never set above 74 degrees (F). Normally it's at 72. I don't like to sweat. Nah, don't be cheap and turn if off when you're away. I would never abuse my house like that.
I leave my condo in FL at 77 when I'm gone, and here in OK at 78 during the day. But 78 at the thermostat here means 82-ish in the main living area, and probably 80 average around the house. In FL 77 is 77. FL is very cheap to cool and for $10 or whatever extra a month I think it might benefit some things like my old photos to be at a reasonable temperature. In Oklahoma any hotter and I'd never get the place cool at night - I need stage-2 running constantly after work to get the place comfortable for sleeping.
Sell the place in OK and go to New Hampsha henceforth in the summahs. Much coolah...
Attempted new signature...

Keepcalm
Posts: 225
Joined: Sat May 13, 2017 7:51 pm

Re: If i turn off central AC will it damage drywalls?

Post by Keepcalm » Sat Jul 15, 2017 1:34 am

The Wizard wrote:
tibbitts wrote:
rgs92 wrote:My central air is never set above 74 degrees (F). Normally it's at 72. I don't like to sweat. Nah, don't be cheap and turn if off when you're away. I would never abuse my house like that.
I leave my condo in FL at 77 when I'm gone, and here in OK at 78 during the day. But 78 at the thermostat here means 82-ish in the main living area, and probably 80 average around the house. In FL 77 is 77. FL is very cheap to cool and for $10 or whatever extra a month I think it might benefit some things like my old photos to be at a reasonable temperature. In Oklahoma any hotter and I'd never get the place cool at night - I need stage-2 running constantly after work to get the place comfortable for sleeping.
Sell the place in OK and go to New Hampsha henceforth in the summahs. Much coolah...
I concur (NH resident).

User avatar
bertilak
Posts: 6058
Joined: Tue Aug 02, 2011 5:23 pm
Location: East of the Pecos, West of the Mississippi

Re: If i turn off central AC will it damage drywalls?

Post by bertilak » Sat Jul 15, 2017 6:14 am

Goal33 wrote:I will start by saying I live in California and have basically no experience with humidity or temperatures managing to get above 80 degrees indoors.

I am just curious, if the concern of folks is humidity, what about a dehumidifier?... what am I missing?
Both heat and humidity can be a problem but humidity is the worst. Think of those pictures of the interiors of abandoned buildings: warped floorboards, peeling walls.

A standalone dehumidifier is a huge bother. It will require running some kind of drainage since there will be no one present to empty the collected water. A standalone will be unlikely to have whole-house capacity and won't address the heat issue.

A decent air conditioner will solve both problems: heat and humidity.
May neither drought nor rain nor blizzard disturb the joy juice in your gizzard. -- Squire Omar Barker, the Cowboy Poet

HoosierJim
Posts: 442
Joined: Wed Mar 24, 2010 7:11 pm

Re: If i turn off central AC will it damage drywalls?

Post by HoosierJim » Sat Jul 15, 2017 6:15 am

One strategy is to get a programmable thermostat and have the temperature brought down to 82 degrees for a few hours starting at about 5 am - 6 am (coolest part of the day). The rest of the day - set the thermostat to 99 degrees so the air doesn't come on. This has two effects
    1. Removes the moisture from the air.
    • Temperature differential is lowest so you move a lot more heat out for the same cost
Then as the temperature increase through the day - the infiltration adds to the moisture - but note the relative humidity is attenuated by the temperature increase.

Image

User avatar
Cosmo
Posts: 1194
Joined: Mon Mar 05, 2007 9:46 pm

Re: If i turn off central AC will it damage drywalls?

Post by Cosmo » Sat Jul 15, 2017 6:40 am

jabberwockOG wrote:Big temperature changes in a house are not good for the structure or the trim, paint and caulk of your house. All materials will expand and shrink at different rates as temperature and humidity goes up or down. Same goes for furniture. Result is cracks and potential warping of materials. Leave HVAC on but set to slightly higher temp in summer (and slightly lower in winter) but nothing too extreme if you are going to be gone for a long period of time. So for example we leave AC at 82 instead of the normal setting of approx 76 if we are going to be gone for a few days or more.
I would not characterize the South as having big temperature changes in the summer. Humidity is the culprit. Here in Texas, 95 max 75 min from June to September.

Back to the OP, my much bigger concern would be hardwood floors and other interior wood trim -not drywall. The drywall would likely be just fine.

Cosmo

User avatar
Cosmo
Posts: 1194
Joined: Mon Mar 05, 2007 9:46 pm

Re: If i turn off central AC will it damage drywalls?

Post by Cosmo » Sat Jul 15, 2017 6:43 am

jabberwockOG wrote:Big temperature changes in a house are not good for the structure or the trim, paint and caulk of your house. All materials will expand and shrink at different rates as temperature and humidity goes up or down. Same goes for furniture. Result is cracks and potential warping of materials. Leave HVAC on but set to slightly higher temp in summer (and slightly lower in winter) but nothing too extreme if you are going to be gone for a long period of time. So for example we leave AC at 82 instead of the normal setting of approx 76 if we are going to be gone for a few days or more.
I would not characterize the South as having big temperature changes in the summer. Humidity is the culprit. Here in Texas, 95 max 75 min from June to September.

Back to the OP, my much bigger concern would be hardwood floors and other interior wood trim -not drywall. The drywall would likely be just fine. I will use the example of our finished, non-climate controlled attached garage. Many times, it is kept open in the summer exposing it to the heat and the humidity. No mildew and no mold to be found anywhere in the garage on the drywall.

Cosmo

carolinaman
Posts: 3208
Joined: Wed Dec 28, 2011 9:56 am
Location: North Carolina

Re: If i turn off central AC will it damage drywalls?

Post by carolinaman » Sat Jul 15, 2017 7:14 am

Cosmo wrote:
jabberwockOG wrote:Big temperature changes in a house are not good for the structure or the trim, paint and caulk of your house. All materials will expand and shrink at different rates as temperature and humidity goes up or down. Same goes for furniture. Result is cracks and potential warping of materials. Leave HVAC on but set to slightly higher temp in summer (and slightly lower in winter) but nothing too extreme if you are going to be gone for a long period of time. So for example we leave AC at 82 instead of the normal setting of approx 76 if we are going to be gone for a few days or more.
I would not characterize the South as having big temperature changes in the summer. Humidity is the culprit. Here in Texas, 95 max 75 min from June to September.

Back to the OP, my much bigger concern would be hardwood floors and other interior wood trim -not drywall. The drywall would likely be just fine.

Cosmo
I agree with the impact of humidity on wood. Our wood floors and doors swell in the humid summer conditions and shrink in the dry winter conditions. Not sure what would happen if we left the AC off for an extended time in summer but it would not be good.

pshonore
Posts: 6420
Joined: Sun Jun 28, 2009 2:21 pm

Re: If i turn off central AC will it damage drywalls?

Post by pshonore » Sat Jul 15, 2017 8:08 am

The Wizard wrote:
MikeWillRetire wrote:
Gill wrote:In Florida you wouldn't dare shut off your air conditioner in the summer.
Gill
What do the poor people do?
I'm guessing they have the equivalent of air conditioning food stamps in Florida...
I imagine people without Central Air open the windows. That should eliminate mold, mildew, etc but would still be uncomfortable in hot, humid weather

User avatar
bertilak
Posts: 6058
Joined: Tue Aug 02, 2011 5:23 pm
Location: East of the Pecos, West of the Mississippi

Re: If i turn off central AC will it damage drywalls?

Post by bertilak » Sat Jul 15, 2017 8:33 am

Cosmo wrote:Back to the OP, my much bigger concern would be hardwood floors and other interior wood trim -not drywall. The drywall would likely be just fine. I will use the example of our finished, non-climate controlled attached garage. Many times, it is kept open in the summer exposing it to the heat and the humidity. No mildew and no mold to be found anywhere in the garage on the drywall.
Interesting point. I too have a garage that is not climate controlled. It is not even attached to the house. I have not noticed water damage to the dry wall other than at a place I can explain in another way. The floor is concrete so no problem their. That makes me rethink my thoughts on turning off air conditioning completely. Perhaps the real problem with humidity is condensation which is caused by temperature differences that may be more moderate in unconditioned spaces -- differences both time to time and air to surface.
May neither drought nor rain nor blizzard disturb the joy juice in your gizzard. -- Squire Omar Barker, the Cowboy Poet

tibbitts
Posts: 7944
Joined: Tue Feb 27, 2007 6:50 pm

Re: If i turn off central AC will it damage drywalls?

Post by tibbitts » Sat Jul 15, 2017 8:35 am

Keepcalm wrote:
The Wizard wrote:
tibbitts wrote:
rgs92 wrote:My central air is never set above 74 degrees (F). Normally it's at 72. I don't like to sweat. Nah, don't be cheap and turn if off when you're away. I would never abuse my house like that.
I leave my condo in FL at 77 when I'm gone, and here in OK at 78 during the day. But 78 at the thermostat here means 82-ish in the main living area, and probably 80 average around the house. In FL 77 is 77. FL is very cheap to cool and for $10 or whatever extra a month I think it might benefit some things like my old photos to be at a reasonable temperature. In Oklahoma any hotter and I'd never get the place cool at night - I need stage-2 running constantly after work to get the place comfortable for sleeping.
Sell the place in OK and go to New Hampsha henceforth in the summahs. Much coolah...
I concur (NH resident).
That idea will have more appeal in twenty-seven months, due to employment.

carolinaman
Posts: 3208
Joined: Wed Dec 28, 2011 9:56 am
Location: North Carolina

Re: If i turn off central AC will it damage drywalls?

Post by carolinaman » Sat Jul 15, 2017 8:48 am

bertilak wrote:
Cosmo wrote:Back to the OP, my much bigger concern would be hardwood floors and other interior wood trim -not drywall. The drywall would likely be just fine. I will use the example of our finished, non-climate controlled attached garage. Many times, it is kept open in the summer exposing it to the heat and the humidity. No mildew and no mold to be found anywhere in the garage on the drywall.
Interesting point. I too have a garage that is not climate controlled. It is not even attached to the house. I have not noticed water damage to the dry wall other than at a place I can explain in another way. The floor is concrete so no problem their. That makes me rethink my thoughts on turning off air conditioning completely. Perhaps the real problem with humidity is condensation which is caused by temperature differences that may be more moderate in unconditioned spaces -- differences both time to time and air to surface.
Garages are more open and get good airflow. Mold and mildew thrive in damp enclosed places with poor airflow, like a crawl space or a house that is not in use.

I have a neighbor who has lived at his lake house for over 20 years. His nearby house has been unoccupied all of that time. I believe it will have to be gutted to the studs and joists and rebuilt. I visited the house recently when he dropped by. I had to leave after 30 minutes due to the musty smell and affect on my lungs. An extreme example but houses need good continuous airflow.

Gill
Posts: 4596
Joined: Sun Mar 04, 2007 8:38 pm
Location: Florida

Re: If i turn off central AC will it damage drywalls?

Post by Gill » Sat Jul 15, 2017 9:01 am

MikeWillRetire wrote:
Gill wrote:In Florida you wouldn't dare shut off your air conditioner in the summer.
Gill
What do the poor people do?
They live with mildew. Easy to understand why Florida was not terribly liveable until air conditioning came along.
Gill

User avatar
bertilak
Posts: 6058
Joined: Tue Aug 02, 2011 5:23 pm
Location: East of the Pecos, West of the Mississippi

Re: If i turn off central AC will it damage drywalls?

Post by bertilak » Sat Jul 15, 2017 9:29 am

carolinaman wrote:I have a neighbor who has lived at his lake house for over 20 years. His nearby house has been unoccupied all of that time. I believe it will have to be gutted to the studs and joists and rebuilt. I visited the house recently when he dropped by. I had to leave after 30 minutes due to the musty smell and affect on my lungs. An extreme example but houses need good continuous airflow.
Never fear, I will NOT be turning off my AC when I am away!

ASIDE:

My AC died about a week ago and I had to replace it. The old one was a single-stage 5-ton system that was slightly oversized for my house. We had a big mold problem a few years back and solved it by wiring up the blower to its lowest speed. (It had three wiring positions, low, medium and high, originally installed at high.) This kept the AC running longer allowing it to squeeze out more moisture. We also cranked the temp down a few degrees and put the fan on auto on/off instead of continuous, as DW wanted it for filtration. (A continuous fan blew air across the collected water right back into the house.) Those three steps (slower fan, automatic on/off fan and lower temp) solved our mold problem.

Our new AC is a 5-stage system that runs quite often, mostly at the lowest stage. It senses humidity and automatically adjusts several parameters. Per installers recommendation I turned off the option that allows it to over-cool. (The old one did that, making the house even colder as it further dehumidified.) The new one is set at 77 instead of 73 and the humidity is kept pretty constant at about 45-47%. (The old AC often let it get to a barely acceptable 55%.)

The new AC also maintains a much narrower temperature range. It has a much fancier, integrated, filter with some sort of electrostatic feature that claims to not only capture but actually kill mold spores. The new AC is as quiet as a mouse. The old one rumbled like a train going by!

These things have come a long way in 10 years.
May neither drought nor rain nor blizzard disturb the joy juice in your gizzard. -- Squire Omar Barker, the Cowboy Poet

Rupert
Posts: 3574
Joined: Fri Aug 17, 2012 12:01 pm

Re: If i turn off central AC will it damage drywalls?

Post by Rupert » Sat Jul 15, 2017 1:47 pm

Goal33 wrote:I will start by saying I live in California and have basically no experience with humidity or temperatures managing to get above 80 degrees indoors.

I am just curious, if the concern of folks is humidity, what about a dehumidifier?... what am I missing?
Central AC is a dehumidifier. Running standalone dehumidifiers large enough to dehumidify an entire house would cost more than running central AC all the time. Standalone dehumidifiers also generate a lot of heat, which you wouldn't want in the south in the summer.
Last edited by Rupert on Sat Jul 15, 2017 1:52 pm, edited 1 time in total.

Rupert
Posts: 3574
Joined: Fri Aug 17, 2012 12:01 pm

Re: If i turn off central AC will it damage drywalls?

Post by Rupert » Sat Jul 15, 2017 1:48 pm

Gill wrote:
MikeWillRetire wrote:
Gill wrote:In Florida you wouldn't dare shut off your air conditioner in the summer.
Gill
What do the poor people do?
They live with mildew. Easy to understand why Florida was not terribly liveable until air conditioning came along.
Gill
Poor people have air conditioning like everyone else. Geez. Most electric utility companies in the deep south have assistance programs for people who truly can't afford summer electric bills. What do poor people in the north do in the winter time?

User avatar
digarei
Posts: 771
Joined: Sat Jul 05, 2014 1:41 am
Location: Sacramento
Contact:

Re: If i turn off central AC will it damage drywalls?

Post by digarei » Sun Jul 16, 2017 4:34 am

Rupert wrote:
Gill wrote:
MikeWillRetire wrote:
Gill wrote:In Florida you wouldn't dare shut off your air conditioner in the summer.
Gill
What do the poor people do?
They live with mildew. Easy to understand why Florida was not terribly liveable until air conditioning came along.
Gill
Poor people have air conditioning like everyone else. Geez. Most electric utility companies in the deep south have assistance programs for people who truly can't afford summer electric bills. What do poor people in the north do in the winter time?
No one had air conditioning 100 years ago; few had it sixty years ago.... are there no wood frame houses from those eras still standing?

I think some posters are conflating personal comfort with structural damage.
Connect with Bogleheads in Northern California! Click the link under my user info/avatar.

The Wizard
Posts: 12168
Joined: Tue Mar 23, 2010 1:45 pm
Location: Reading, MA

Re: If i turn off central AC will it damage drywalls?

Post by The Wizard » Sun Jul 16, 2017 4:44 am

digarei wrote:
No one had air conditioning 100 years ago; few had it sixty years ago.... are there no wood frame houses from those eras still standing?
Mildew and mold have gotten more aggressive in the last few decades.
They eat Chinese drywall for lunch nowadays...
Attempted new signature...

neilpilot
Posts: 1830
Joined: Fri Dec 04, 2015 1:46 pm
Location: Memphis area

Re: If i turn off central AC will it damage drywalls?

Post by neilpilot » Sun Jul 16, 2017 6:30 am

The Wizard wrote:
digarei wrote:
No one had air conditioning 100 years ago; few had it sixty years ago.... are there no wood frame houses from those eras still standing?
Mildew and mold have gotten more aggressive in the last few decades.
They eat Chinese drywall for lunch nowadays...
...and no one had drywall 100 years ago

Post Reply