There are also "whole house fans" which blow air from the house into the attic at high CFM rates. Those are belt driven and due to the high velocity are really noisy.
They are not all that way. There are direct drive (also noisy) and remote mounted, lower CFM, quiet versions (with electric doors)
You've been using the term "ECM motor" quite a lot, so I had to do the googles.
Yeah, ECM is basically a vrf controller integrated to the motor body.
... unlikely to filter the air with the ahu panels off...
This is because elderly people usually have poor blood circulation to the extremities. They suffer greatly in cold winters and that is why so many of them retire to Florida, southern Texas, southern Arizona or southern California. Long ago in Riverside I saw numerous old folks who would sit indoors, in 100+ degree summer days, with the AC completely shut off.
Welcome to PG&E's torture chamber. Last year they managed to talk the state PUC into allowing them to slowly increase residential electric rates, because "Oh dear, well you know, we just came out of a terrible terrible bankruptcy and we just NEED better profit margins to survive" blah blah. This is a corporation that went bankrupt because it was literally found guilty of murdering 86 people in Paradise in 2017. Several of the worst NorCal fires in the past five years were started by faulty PG&E equipment, or trees they failed to trim falling onto their transmission lines. Oh, I could tell you so many horror stories. Sometimes I seriously wonder if they are bribing state government regulators to look the other way.
apnews.com
Ha ha ha, don't kid yourself. That "silliness" has been extremely contagious for the past 50+ years.
Just like SDG&E and SCE will be paying for the decomississioning of S.O.N.G.S. 2&3 for the next 5 decades. ...finished my apprenticeship there while it was still under construction. I think peak for SDG&E is 49 cents. Folks here in my region that think they are immune from high rates might be in for a rude awakening. Right now a lot of our power here is coal fired. Coal just lost a lot of popularity with the passage of the IRA. That's what I mean about the nation following California in this case. That's why I'm making the moves I'm making.
Silliness eh? Where ya from, N.C? Tx? Yeah I think there's plenty of silliness spread out all over the country these days.
Well stop heating the attic.
If only vs motors didn't cost 3x as much to replace, are more prone to condensate pulloff damage, not normally stocked.
There is a little more to them than that. The motors are brushless, direct current designs, and allow for direct drive in many applications where it was traditionally not viable. Specific to the heating ventilation and air conditioning industry, they essentially integrate a variable frequency drive and enough smarts that they can do proportional, integral, and derrivative control algorithms internally, so if you have a 0-10 volt or 5-20 milli-amp sensor you don't need any further smarts to control them.
Is it still? When I visit family in St. Louis I barely see any coal trains any more. It used to be 2 or 3 3-4 mile long trains per day passing through; I haven't seen any my last few trips back.
Vertical Trane/American Standard AHU supported by made on job site, 2x4 and duct board, plenum. Return air is drawn into plenum below the AHU. Air then flows through the filter, coil, blower and past the heat strips at top of AHU. Removing the filter access panel and blocking off the return air grills will have the air coming in through the removed access panel hole, through the filter, coil, blower and past the heat strips. Other than having the AHU in the attic or a closet, this is the only way I have ever seen air to air heat pumps installed in FL. This idea would also work if the AHU was in the attic. The intake air would probably be hotter and removing the filter access panel, possibly daily, would be a pain in the ass. I have a direct drive whole house fan with shutters, but quit using it after I came up with the AHU idea about 15 or 20 years ago.
This from the google machine;
I guess that answers my question about their cost effectiveness, probly a lot more cost efective to add an extra panel.
Yes, unless you do hvac for a living, split hp systems above 16 SEER can be very expensive up front and to repair, even under the 10 yr part warranty.
We just went through a really bad heat wave and a buddy in the next town over was having trouble with his a/c blower on his outdoor package unit not coming on when when it called for cooling. He could hear the compressor kick in but the fan wouldn't start. So he called the local hvac professional and they came out to troubleshoot the problem. When the service tech arrived mu buddy Mike says to him, "I think that control board is bad. I've heard they have issues." The tech made note and went out to check the unit. He returns in about 20 minutes and says "Yup. That's the problem. I'll get one ordered for you."
