My feelings are not hurt , nor do I wish to debate you when it's obvious you're more worried about being right than trying to understand a different point of view . If you think a dirty filter is the better way to roll then have at it . Different strokes and all of that ...
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- Thread starter factorytuned2012
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I have been reading up on blower speeds and most are saying it should be set to 400 CFM per ton of AC. After looking at my air handler document, I adjusted my speed from high to low and it does make a difference. Most blower speeds are set to high by default. I think you need to be careful in not setting it so low the system freezes up. Do any of you mess with your fan speed setting?
I would keep an eye on the temperature drop across the coil.
18f-23f is in the acceptable range.
I would also keep an eye on the rooms farthest away from the unit and smaller bathrooms.
Some of the newer units with varible or multi-speed compressors will also slow the blower automatically.
I'm not an engineer, but I would think the lower blower speeds would lessen the amount of air going down the smaller ducts.
18f-23f is in the acceptable range.
I would also keep an eye on the rooms farthest away from the unit and smaller bathrooms.
Some of the newer units with varible or multi-speed compressors will also slow the blower automatically.
I'm not an engineer, but I would think the lower blower speeds would lessen the amount of air going down the smaller ducts.
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This is standard modern construction practice.
There is typically a secondary return grill in the master bedroom. This keeps a nice mix of air as the unit cycles on and off with the bedroom door closed. More or less you don’t have to worry about the bedroom getting too hot or too cold in winter if the door is closed because it’s drawing air from within the bedroom itself and mixing it in with the rest of the house.
Very odd, with an undersized unit, the humidity levels would tend to be on the lower end since the compressor and evaporator coils are constantly running, removing moisture from the air.
If the system was more robust, you would get Cooling air fast and the unit would run less often, removing less moisture from the air where it would be clammy inside.
A perfect example would be condos and hotels along the shore in Myrtle Beach. If you ever check into one, you get ice cold, fantastic air conditioning, but they’re clammy as heck and the reason that is the systems are well oversized to keep the room cold, but they can’t remove enough moisture.
Somethings not adding up. I’m curious myself. We have a similar home not far from you and if the unit runs constantly such as about a week ago, when the humidity was very high, plus we had a house full of out of state company with the oven going. It’s true. The unit was struggling to get the temperature down to the set-point in fact, it failed in doing that, I was actually surprised as our house is one year old and I haven’t had this happened to me before but the humidity level was low because it was constantly running removing humidity.
Still, I was wishing for just a little bit more, but for the reasons that I just posted above, not too much more.
There is one thing you could do and I’m going to either do it myself or I’ll get the original installer back here, but I refuse to pay him a diagnostic fee. If anything I’ll buy my own gauges and Freon sometimes just adding a half a pound or a pound of Freon can make a difference I just want to stress that air conditioning companies that know what they’re doing in Very humid places will make sure not to oversize a unit or else you will have a moisture problem inside the house..
It really is a balancing act, and of course, with everything and energy efficiency nowadays may be a little bit more so.
It would be cool to know if you ever had anybody look at it or if you intend to, hopefully you will update. We are in very similar circumstances, but our problem is not as extreme as yours. Our issue that day was as you know the blaring hot and humid days we had just over a week ago now I guess, and a house full of company and oven going, I think the temperature was climbing up to 78 or 79 and the thermostat was on 75.
However, foolishly, maybe I should’ve set it at 75 to begin with initially it was set at 77 and once I lowered the temperature it didn’t go down. It actually actually went up another degree or two.
But one thing for sure inside the house it’s nice and dry
You know we just had a new Honeywell T5 Wi-Fi thermostat by our electric co-op put in and I just realized I can’t find the humidity level that we had on the Honeywell T5 Z wave thermostat. Anyway, this was the week which I’m sure you remember, it’s been a crazy summer to begin with. It was that Saturday of the most struggle even though it looks like Friday was pretty heavy too
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this is very interesting similar situations. Had the original installer look over the install while the house was under the 1 yr warranty was told everything is functioning as should be. One hour heating and air gave me the same answer all though one hour admitted the unit is undersized. Original installer is tech service heating and cooling.
Is your system multi stage?
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Single stage
Dang I was hoping you'd say multi stage. My brother has a 4 ton system that was running constantly with high humidity and we found out (no AC tech did) that the damper/load controller used was not able to activate the high stage. Once we figured that out all his AC problems were fixed.
I would still peek at the outside units user manual for any verbiage of running at least than full capacity, you never know... Do you have the model number?
Worst case id invest in a minisplit they are fairly cheap and can be set to dehumidify. They don't all have to be ugly wall mounted ones though those are the easiest to install.
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I spoke with an AC tech that service’s my job he suggested a whole house dehumidifier said with the dehumidification assistance it would add around 1/2 ton of cooling ability to the unit.
I had my first ever home inspection done right before the one year ended. The output and input spread was around 15 or 16 degrees at the time. I honestly cant remember other than I check myself as well. There were no problems with the system except one loose duct missing some insulation and leaking some air. That was repaired. I do wish now I asked them to check the freon. System was installed wintertime house was completed in March 2023
and ... I can see you posted to someone else you also have a Lennox. (I'll get back in another post.)
Anyway, the spread was always good meaning 14+ degrees. But on that day almost 2 weeks ago it was only 11 or 12.
I need to pay more attention to it this week moving forward, sadly it is not going to be as hot and humid though.
Im wondering if you also have a fresh air intake inside the main air box. A flapper opens when the system turns on to bring in fresh air. I guess because the house is sealed well.
I have noticed for a long time, builders state in their warranties that the AC should not be expected to cool below 75 degrees and is not covered under warranty. I just found some interesting statements pertaining to that from our installer on the BBB site when people complained. Granted there are not a lot of complaints about this company and they seem responsive, it just rubs we the wrong way that purchasers are supposed to accept the major climate control system of the entire home, that should function properly for at least a decade is covered by a one year warranty from the company that installs it.
I found this interesting, (I am not in anyway defending a company) I do see why the warranties mention 75 degree now. It seems things are calculated so closely that they do not always get it right, obviously .
Here is a clip from the link below. I found it an interesting thread. I do need to know what is required as far and input and output spread. You sound like you had some competent people at your house. Fogel was out company and I believe they are in SC too, we are right over the border in NC Calabash Area
This is the link, it's a good read going through the complaints and the company response.
https://www.bbb.org/us/sc/ladson/pr...r/fogel-services-inc-0663-34010794/complaints
Looks like there is nothing there it, hooks directly to the unit outside via two wires (Y1 and C) so its either in or off. I wonder if the thermostat is not running the compressor all the time? Air coming out of the vent always cold?
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From what I can tell yes. Air handler runs along with the condenser minus a few mins I’ll hear the thermostat click off soon after the air handler is off. I know some units will run the blower longer to scavenge the remaining air to dry up the coil
Most of you are probably aware that you need to reference YOUR exact filter dimensions. A 20 x 25 does not mean another brand 20 x 25 will fit properly. I've seen 1/4-1/2" variations in both dimensions. Just a way to get you to pay more for their brand, but if you look you can find one that fits, just have to check. On a side note, when I had our Central put in (3 ton Carrier) I had them use a return grill in the ceiling that can use a 1" cheap-o filter before the 4" downstream one up in the attic. Kinda like a K&N rock-catcher LOL.
I wish I knew how to read this stuff, but face value its seems our unit for our 1800 sq ft house is larger. I have no clue where or how to find tonnage. Also what about the air handler/evaporator? How does one determine if it's properly sized with the condenser/compressor?
This is what I found for your model
https://www.lennox.com/residential/products/heating-cooling/air-conditioners/ml14xc1
This is our model
https://www.lennox.com/residential/products/heating-cooling/heat-pumps/ml17xp1
I did wash down the coils with a hose last week, fair amount of mud from construction but doubt that was on the coils.
Looks like a 2 ton....
Also if I am reading the BBB complainants correctly, for our area, if it is 92 degrees out the unit needs to be designed to maintain only 75 degrees inside.
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2ton. 024 in the model number. 1 ton is equal to 12,000 btu
THANK YOU! *LOL*
Ive been around refrigeration of all sorts before many some here were born *LOL* But one thing that always got me (even on my last home that had two units) was telling the Tonnage.
Our last units in the house we sold back in 2022 were Heil builder supplied and I know a lot of people in here are into the late most complicated designs I like simple and clean. Less to break and if they do break, readily available parts AND techs that understand basic systems. Anyway, the Heil basic units were running in a 3000+ sq ft home pretty much trouble free (one condenser fan motor, 2 capacitors, one contractor, all replaced by me) Both units still running strong after 16 years in the Columbia SC area of scorching hot summers (more hot then here at the coast but less humid) in this home, we NEVER opened a window, units ran all year long both for heat and cooling but main floor was a gas heat unit inside the blower box.
So I am good with the basic Lennox. I guess it wouldnt have hurt to have a 2.5 ton for you and maybe me too.
Im going to keep an eye on the temperature spread of intake and output. I believe it should never be below 15 degrees.
My old house, with the older freon and my own set of gauges I adjusted early on and pretty much had the differential trouble free at a solid 18 degrees. So two weeks ago, I was measuring 12 degrees on that hot day with many people in the house and the one going... well, still trying to understand that.
One thing I didnt see if you replied, do you have an outside air intake inside your main filter box? We do and I was wondering if the was contributing to the less than stellar performance on that hot week
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