HVAC filters

[KrisZ]

They must’ve updated the code to allow this cheap way of bringing fresh air into the house.
Normally you need to use an HRV which conditions the air before it gets into the air handler.

 

[alarmguy]

They must’ve updated the code to allow this cheap way of bringing fresh air into the house.
Normally you need to use an HRV which conditions the air before it gets into the air handler.

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I dont know what is up in the attic but if this piece of equipment isnt there I wouldn't care. I like simplicity

 

[KJSmith]

If your home is really tight, there would have to be a way of losing as much air as you are bringing in.
The dirty filter tells you air is coming in.
So, air is escaping somewhere.

Bringing in outside air is nothing new to the industry.
Its common in large buildings.
The better building management systems use enthalpy programs to determine when/if it's worthwhile energy wise.
They take both temperature and humidity into consideration.

 

[alarmguy]

If your home is really tight, there would have to be a way of losing as much air as you are bringing in.
The dirty filter tells you air is coming in.
So, air is escaping somewhere.

Bringing in outside air is nothing new to the industry.
Its common in large buildings.
The better building management systems use enthalpy programs to determine when/if it's worthwhile energy wise.
They take both temperature and humidity into consideration.

Oh yeah, first thing I thought with the dirty 6 x 6 filter is I know it’s working.
I also checked it without the filter, turned on the AC unit and the flapper opened up.

It would be easy to lose that volume of air coming in the intake while other air is pushed out besides normal however small gaps in doors and windows you have the clothes dryer and hood over the range which would be especially easy to push air out. Actually just one of them is probably sufficient however, I’m sure all rooms equally lose some air. I would imagine at least a little bit.

It’s certainly not a powerful force of air being sucked coming in, but holding your hand there you can feel it. I even questioned the need for it, but whatever it’s there it would be easy to disconnect, though I have no intention.

Yes, I know it is very common with commercial buildings, it’s actually amazing science when it comes to them. Including positive pressure in stairwells and stuff like that. Things we never think about.

My best friend since birth and that was a long time ago was a senior vice president for international air-conditioning (climate) engineering firm. He was with them for life.
He started sometimes seven days a week almost 40 years ago on a drafting table with the schematics and diagrams that were ginormous and worked his way up from there. he used to complain about contractors who would swap out expensive equipment for cheaper equipment and then have issues

They do big buildings all around the globe, skyscrapers. I was always fascinated by it, but he paid more attention in college than I did.

With that said, I never saw anything like this until now in an average production type residential home until we just moved into this house.
It still can’t be that common because it was a ***** (pain) trying to find the filters, but I have a good source now I’d have to buy them and lots of 12

 

[factorytuned2012]

Just another fine day over 90 degrees in the Carolina’s.

 

[rekit]

If your clothes dryer is in your house it could remove a lot of conditioned air every time it runs. That's the reason I put ours in the garage. I built our home in the 80's, and at the time my brother had been fired from his job as Air Traffic Controller by Reagan and was working at a Radio Shack to get by. At Christmas I asked him for two of the Electronics Cooling fans they sold as a cheap Xmas gift. I was going to use them for bath exhaust fans as I hated the noisy ones I had seen, and as such they had no auto-closing doors on them. Several months went by as I finished building the home, and one day I noticed that running the fan in one bathroom would spin the other one backwards. Later I got some really nice fans with good doors on them. 1500 sq ft one story. I was impressed!

 

[factorytuned2012]

If your clothes dryer is in your house it could remove a lot of conditioned air every time it runs. That's the reason I put ours in the garage. I built our home in the 80's, and at the time my brother had been fired from his job as Air Traffic Controller by Reagan and was working at a Radio Shack to get by. At Christmas I asked him for two of the Electronics Cooling fans they sold as a cheap Xmas gift. I was going to use them for bath exhaust fans as I hated the noisy ones I had seen, and as such they had no auto-closing doors on them. Several months went by as I finished building the home, and one day I noticed that running the fan in one bathroom would spin the other one backwards. Later I got some really nice fans with good doors on them. 1500 sq ft one story. I was impressed!

Yeah we don’t use the dryer during the peak heat of the day

 

[alarmguy]

Just another fine day over 90 degrees in the Carolina’s.

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You know keep thinking about the "Humidity" on that Stat. I cant help wonder if it is indoors or part of the weather forecast above.
I only wonder because 71% seems way to high in A/C mode if it is interior I would question the accuracy

Ahhh ... I just looked it up = in door Humidity, wow that seems high, I would question that reading, maybe you have something to compare. I think one other time you posted and it was even higher than that.

 

[factorytuned2012]

You know keep thinking about the "Humidity" on that Stat. I cant help wonder if it is indoors or part of the weather forecast above.
I only wonder because 71% seems way to high in A/C mode if it is interior I would question the accuracy

Ahhh ... I just looked it up = in door Humidity, wow that seems high, I would question that reading, maybe you have something to compare. I think one other time you posted and it was even higher than that.

Here’s humidity at 9 o’clock this morning if I can measure humidity another way and see if there’s a difference I can’t fine tune the stat in settings.

 

[alarmguy]

Here’s humidity at 9 o’clock this morning if I can measure humidity another way and see if there’s a difference I can’t fine tune the stat in settings.

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Im curious about our house now. We had a Honeywell "Home" T5 Zwave and it had humidity on it. I don't recall ever seeing it higher than the mid 50s (but I can be wrong) We had our electric co-op install a new WiFi T5 which is also updated and they left the humidity off it. The older version of the T5 was a while LCD screen, the new version (to update the look) is a black screen much like what you have but they left the humidity out.

Frustrating, I had some interior thermometers with the display but either thrown out of lost in the move. Im going to get another because I am curious now. Im no expert but until just now I think I saw your display showing up in this thread 2 times in the 70s
I cant saw much without one in my house now but will soon.
Interesting app you got there. Honeywell is more basic (lack of better words) works well though and I do love the "Circulate" function when people sleep over.

PS. I just ordered an Accurite, which will come in handy as will record high and low humidity and temperature. I make an effort to make sure rooms are balanced and that is tricky when you are sleeping but anyway, we are Walmart+ customers and same day delivery (shipping) Amazing.

 

[factorytuned2012]

Yes I have my fan circulate 15% or 9min on the hour. This is only the sensei lite thermostat. The better model has even more features.

 

[alarmguy]

Yes I have my fan circulate 15% or 9min on the hour. This is only the sensei lite thermostat. The better model has even more features.

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I can see why that is such as respected thermostat, I didnt know others offer CIRC and you can adjust it, VERY cool. It would have been my choice IF I didnt already have the Honeywell T5 zwave on the wall, yet my understanding that Honeywell was the only one with this feature also played a part. The T5 Wifi Honeywell was a direct plug in with the already in place optional trim ring. I was afraid if another thermostat was used, removing the trim ring might have meant some minor patching and painting. I love options and it's cool you can adjust the fan run time. I dont need more than that. Meaning the more expensive Sensi line. I dont believe in separate sensors etc.

I had to pay our co-op $25 for the Honeywell and the Sensi was free at the time. Now this month (or quarter) the Honeywell is free (go figure) I should let my wife call them for the $25 I would be too embarrassed. *LOL*

 

[factorytuned2012]

I can see why that is such as respected thermostat, I didnt know others offer CIRC and you can adjust it, VERY cool. It would have been my choice IF I didnt already have the Honeywell T5 zwave on the wall. The T5 Wifi Honeywell was a direct plug in with the already in place optional trim ring. I was afraid if another thermostat was used, removing the trim ring might have meant some minor patching and painting. I love options and it's cool you can adjust the fan run time. I dont need more than that. Meaning the more expensive Sensi line. I dont believe in separate sensors etc.

I had to pay our co-op $25 for the Honeywell and the Sensi was free at the time. Now this month (or quarter) the Honeywell is free (go figure) I should let my wife call them for the $25 I would be too embarrassed. *LOL*

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That’s a handsome looking thermostat however. Yes, I could join my co op electric I just don’t want them meddling with my comfort settings for a one time $50 in bill credits

 

[alarmguy]

That’s a handsome looking thermostat however. Yes, I could join my co op electric I just don’t want them meddling with my comfort settings for a one time $50 in bill credits

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Yes, seems like all CO-OPs (at least) offer these. Even the wording on the website. I think it's a third party who handles it for the co-ops but a co-op employee does do the install. We didnt do it on the last house.

I agree on the messing with the settings but went for it anyway as I wanted my zwave stat replaced as I threw out all the Amazon smart features that the builder installed and were tied to Ring (there were A LOT). The only way to do it was going Wifi.
So for the heck of it, I opted for them to do it at a total cost of $25. They adjust max of 4 times a month, max 4 hours each time but have never seen more than 3 hours), you can override a certain number of times if you wish, if you override too much, you lose the $50 a year. We actually had an "Energy Savings Event" two days ago, since we were home I turned the thermostat down two degrees a half hour before the "event" SO the net was only up 1 degree once they raised it 3 degrees for 3 hours. Also if your thermostat is programed, it will still adjust the schedule during an energy savings event but at 3 degrees warmer Or colder in the winter.
I do get not wanting to lose control, decided to just go for it and it works out ok, wife wasnt as sure as me *LOL* Im just ok with anything in the 70s in the house but also someone who cuts the lawn midday at the hottest time of the day.

One thing I can tell you, born raised spent most my life on Long Island NY electricity is DIRT CHEAP here. I thought the midlands/upstate of SC was cheap. Now on the NC side of the boarder even cheaper at 10 cents a kWh.
When I left Long Island almost 2 decades ago it was 20 cents.

 

[alarmguy]

@factorytuned2012
AS you know the Humidity reading on your thermostat made me curious so I bought a meter in Walmart. It's only about $14 and maybe you want to check it against your stat. Kind of neat, records high and lows over 24 hours.
Right now I am at a high because it went from 72 degrees sleeping to the current 77. So the AC have not come on for hours, it will shortly now that the house made it to 77 daytime. (though when home we typically put it at 76, I forgot until just taking this photo)

Anyway, bottom line is with AC running we are always in the middle 50% and most all times lower. AS you can see, despite the rain last night and today. It was down to 48% with the system running. I think it may be worth looking further into if it turns out your stat humidity it correct.
Maybe a major intake leak or something in the attic. Dont know.

Again, this current 57% peak is only due to the system not on for a few hours of this rainy day. It takes a while climbing from the sleeping temp of 72 to get to 77 before the system turns on again. IN the meantime humidity increases until it does. Once the system starts cycling on and off it drops surprisingly fast. I think I can see why now, with the new building standards and windows/insulation, even the insulation about the flex ducts is higher how for our house the 2 ton unit seems to be right.
My son with a 20 year old house in the update of SC as noted has a 2.5 and a family member in N. Myrtle has a 3 ton unit all homes about the same square footage. I suspect your AC guy was correct and maybe needed a 2.5 ton.

As I have been carefully watching our own system now because of what I thought was a past issue and reading about yours. I was telling my wife last night that we seem to be running correctly here.

I wasnt going to post the photo below because it was out of "normal" We were out on the boat yesterday, since our thermostat was set at 82, little did I know there would be an "energy savings adjustment for three hours) So even with a peak of 84 degrees on a HOT sunny day our Humidity never went above 52% For most the day the unit didnt turn on until the "energy savings event" was over. By this time I was home and I was noticing a 3 to 4 degree drop per hour. (if I remember correctly) that is when I said to my wife that we are good with the system.

I cant help wonder why your humidity is so high compared to ours unless the meter I bought is bad but I think correct. Our house feels dry too. I wonder if something else is in play and why I thought maybe an attic duct leak or something... Im clueless but I like puzzles.

 

[KrisZ]

This should not be a mystery to any competent HVAC tech, but apparently OP has not found a good one yet.

 

[factorytuned2012]

@factorytuned2012
AS you know the Humidity reading on your thermostat made me curious so I bought a meter in Walmart. It's only about $14 and maybe you want to check it against your stat. Kind of neat, records high and lows over 24 hours.
Right now I am at a high because it went from 72 degrees sleeping to the current 77. So the AC have not come on for hours, it will shortly now that the house made it to 77 daytime. (though when home we typically put it at 76, I forgot until just taking this photo)

Anyway, bottom line is with AC running we are always in the middle 50% and most all times lower. AS you can see, despite the rain last night and today. It was down to 48% with the system running. I think it may be worth looking further into if it turns out your stat humidity it correct.
Maybe a major intake leak or something in the attic. Dont know.

Again, this current 57% peak is only due to the system not on for a few hours of this rainy day. It takes a while climbing from the sleeping temp of 72 to get to 77 before the system turns on again. IN the meantime humidity increases until it does. Once the system starts cycling on and off it drops surprisingly fast. I think I can see why now, with the new building standards and windows/insulation, even the insulation about the flex ducts is higher how for our house the 2 ton unit seems to be right.
My son with a 20 year old house in the update of SC as noted has a 2.5 and a family member in N. Myrtle has a 3 ton unit all homes about the same square footage. I suspect your AC guy was correct and maybe needed a 2.5 ton.

As I have been carefully watching our own system now because of what I thought was a past issue and reading about yours. I was telling my wife last night that we seem to be running correctly here.

View attachment 238439

I wasnt going to post the photo below because it was out of "normal" We were out on the boat yesterday, since our thermostat was set at 82, little did I know there would be an "energy savings adjustment for three hours) So even with a peak of 84 degrees on a HOT sunny day our Humidity never went above 52% For most the day the unit didnt turn on until the "energy savings event" was over. By this time I was home and I was noticing a 3 to 4 degree drop per hour. (if I remember correctly) that is when I said to my wife that we are good with the system.

View attachment 238440

I cant help wonder why your humidity is so high compared to ours unless the meter I bought is bad but I think correct. Our house feels dry too. I wonder if something else is in play and why I thought maybe an attic duct leak or something... Im clueless but I like puzzles.

I appreciate that and will pick one up next trip to Walmart. Thank you

 

[KJSmith]

@factorytuned2012

Can you get a return and supply air temperature while the unit is running.... preferably for several minutes?
Try to get a supply vent close to the fan unit.
Do you know approximately how long it runs each cycle?

I'll assume you have longer run times if you are not keeping set point.

Also....post #169.... cooling cycle rate in your TStat settings.... have you ever tried adjusting that, so you get a longer run time?

 

[KJSmith]

This should not be a mystery to any competent HVAC tech, but apparently OP has not found a good one yet.

This is a simple unit. No real provisions for humidity control.
An HVAC tech can come out and see if the unit is cooling or running correctly.

Lowering the humidity is a byproduct of removing heat from the space.
If the unit is sized correctly by the engineer... it will usually control humidity.

 

[KrisZ]

This is a simple unit. No real provisions for humidity control.
An HVAC tech can come out and see if the unit is cooling or running correctly.

Lowering the humidity is a byproduct of removing heat from the space.
If the unit is sized correctly by the engineer... it will usually control humidity.

I realize this, but we have to look at two things not just one in isolation, the unit cannot keep the set point and the humidity is high.
This, to me, leads to a leaky return somewhere in the attic, since the unit was already looked over and deemed to be operating normally. It would be easily confirmed by measuring the return air temp. Again basic stuff especially for an HVAC tech.

Edit:
Here is the humidity my Nest thermostat is reporting at 50% downstairs. The upstairs one is showing 53%. Not sure how accurate it is, but the house is cool and comfortable, so I take it’s pretty close.