In the video, the outside condenser/compressor unit came pre-charged with a quantity of R-410A refrigerant with the assumption that the typical line set will be approximately 15' long. At the 34 minute mark in the video, the installer added supplemental R-410A since his line set was actually 30' long to compensate for the difference. If you go back to the thread on HVAC-talk.com and look at Post #28, you will see the label indicating a factory pre-charge of 8.3 lbs. of R-410A.
HVAC filters
- Thread starter factorytuned2012
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Thank you for explaining that because then it flips me around again, meaning I should check my Freon level just to be sure because some may or may not have been added at the time of install.
I took precharged as lines precharged at a certain length and snap together like many ductless systems.
Keep in mind I’m just a consumer. But can now see on unit for an 1800 square-foot house a 2 ton unit is barely sufficient.
A family member in North Myrtle Beach 20-year-old house or almost 20 years old has a 3 ton unit for the same square footage.
Compared to the old days this house has r15 in the walls over our 38 in the attic, low eglass throughout. Something must make a difference because for the most part, the house is always comfortable and the unit cycles on and off like today. I have a set for 76 cycling on and off throughout the day 85 and blistering sunlight hitting the house, we have no trees. But the air is dry and 85 isn’t exactly hot.
I really appreciate your input so just in case don’t misread any of my words the wrong way as debating you
14 foot sloped down to 12 ceiling in kitchen, 12 down to 9 in living room. Doors are a bit leaky and windows could stand replacing.
I thought 2 tons for it would be overkill. I think it's the ceiling that really kills it, especially in the kitchen. Traps a ton of heat.
Unit is 15 months old.
Check what your air handler allows for, mine allows up to .8" of water. I change it around .60" about double of new filters.
I use whatever has the lowest pressure drop, which coincidentally IS NOT the cheapest lowest MERV ones.
Good point the problem is there are good and bad filters in all Merv ratings and a staggering void of complete testing including long term testing and not just brand new testing. So unless you can find a source with reliable testing it is tough. Also the point of diminishing returns, a super high quality hi merv with low pressure drop may not be that low after 8 weeks. I just change whatever generic cheap filters I can every 3 months for the 2 in my system
I USED to buy 5inch return grill filters and run them 6 months to a year, last house had 4 of them and gets pricey, so figured cost difference in this new home, Ill just change cheaper 1 inch filters every 3 months.
Consumer reports used to test them, Im not sure if they do anymore, but even so, just a handful out of dozens of brands out there.
BTW- I agree with you but because of this I just buy generic Merv 8s and 11s since I have two intakes usually the smaller filter will be 11. but I dont have an opinion on 11s except I would never have two running at the same time. No need for it, prefer 8 and the max.
Now your post is making me re-think the subject again, that I have been thinking about and analyzing for the last 16 years
I’ve noticed the higher MERV filters tend to not bow nearly as bad (if at all) as the cheaper ones after 20 days of system run time.Good point the problem is there are good and bad filters in all Merv ratings and a staggering void of complete testing including long term testing and not just brand new testing. So unless you can find a source with reliable testing it is tough. Also the point of diminishing returns, a super high quality hi merv with low pressure drop may not be that low after 8 weeks. I just change whatever generic cheap filters I can every 3 months for the 2 in my system
I USED to buy 5inch return grill filters and run them 6 months to a year, last house had 4 of them and gets pricey, so figured cost difference in this new home, Ill just change cheaper 1 inch filters every 3 months.
Consumer reports used to test them, Im not sure if they do anymore, but even so, just a handful out of dozens of brands out there.
BTW- I agree with you but because of this I just buy generic Merv 8s and 11s since I have two intakes usually the smaller filter will be 11. but I dont have an opinion on 11s except I would never have two running at the same time. No need for it, prefer 8 and the max.
Now your post is making me re-think the subject again, that I have been thinking about and analyzing for the last 16 years
That being said, the Filtrete filters have the pressure drop ratings listed on them.
125 sq inches per ton of cooling
Grill will decrease surface area 20%
2 returns so it will pull air from two areas can't have a return air to big
Yes, true, I dont like the bow.
I get the pressure drop but I dont know what happens 30 days into using the filter, if it is too efficient I can't help but want to know what would the pressure drop be in 60 to 90 days if its catching all the smallest particles are they then clogging it up more than normal?
Only for the super efficient and why I like Merv 8 but now that the subject has come up next search I do will look for stats.
I order quite a view at a time and just getting into a bunch of Home Depots HDX labeled filters bought on price. Mere 8 and/or 11
With all the above said, I do agree and wouldn't mind quality 8 and 11 filters, I just dont know if they exist.
I will stick for a MERV 5 or less and change every 20 days. It has worked for me.. When my Goodman was replaced after 20 years of sevice the blower motor cage and the evap were clean...Evan the HVAC tech commented on how clean it was... So like I said I use them with good luck and get great air flow through the vents too...
Looks good and they publish all the filter stats on their website, nice to see.
https://www.glasfloss.com/wp-content/uploads/2021/08/06-PLEATED-BROCHURE-081921.pdf
https://www.glasfloss.com/product-categories/z-line-pleated-series-filters/
https://www.glasfloss.com/product/zl-hv/
I go with the Home Depot HDX brand at our beach house...FPR 4=MERV 8 and change every 2 months.
Works fine. I used to use the cheap glass spun filters in summer with the AC running and than switch to the Filtrete pleated ones for winter. System lasted 24 years problem free. Payne/Bryant single stage furnaces are work horses. Replaced the old Payne with the similar current model Bryant 2 years ago.
Just replaced the Honeywell Wi-Fi thermostat with a Google Nest a month ago. I liked the Honeywell better but the Nest gets the job done just fine too.
Works fine. I used to use the cheap glass spun filters in summer with the AC running and than switch to the Filtrete pleated ones for winter. System lasted 24 years problem free. Payne/Bryant single stage furnaces are work horses. Replaced the old Payne with the similar current model Bryant 2 years ago.
Just replaced the Honeywell Wi-Fi thermostat with a Google Nest a month ago. I liked the Honeywell better but the Nest gets the job done just fine too.
Mine allows 0.75, but derates the airflow setting above 0.5". If you use 0.5" of your budget on the return side, what's left for the rest of the system? Any time your blower isn't sucking against as much of a vacuum, it isn't using as much electricity. (delta p loss) Lower is better. Pressure drop across the system doesn't help anything.
A 4" magnahelic 0-1" differential pressure gauge was $30 on ebay. I cut a 4" hole in a scrap of plywood and installed it next to the air handler. Filter specs from manufacturers are nice, but the cost of the gauge vs endless swapping of filters, the gauge pays for itself.
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The best part about the glassfloss Z filters is that their deeper models (2" and 4") have cardboard fingers to keep the pleats separated.
Some of the cheaper brands...the pleats collapse together. Effectively the filter area is lost when this hapens.
Running fan all time in cooling mode will increase humidity in home. Set fan to auto when cooling.
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This is a technique when the blower is beginning to fail, I learned.
An indie guy told me a 20 yo furnace is like an old man or an aging hooker. They can’t blow as well as they once did. This clicked. Because I said how come I could use $8 3M filters 2002-2016, and today, I can’t?
Again, I get this concept applies to PSC motors. If it only had 3 speeds and suddenly the best short cycles on medium, you can go to high and buy cheap filters to avoid replacement. But with a modern ECM motor I use what was recommended, and it’s 4”.
Please explain exactly how that happens.
The partially true theory is that with the blower running, the vacuum level in the plenum causes there to be a higher level of condensate in the catch tray under the coils. Since the air never stops moving, this water re-evaporates into the air moving through the system back into the living space...until the system cycles again and proceeds to re-remove some of what it already once-removed.
This ignores any other intricacies of the installation...ductwork losses, etc.
If the drain is plumbed correctly, that should not happen.
Blow across coils should have a "T" and suck across coils should have a "P" trap.
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