New gas furnace/AC recommendations?

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PSC blower motors are not really multispeed at all. All the extra speed taps are are taps on what acts as an internal autotransformer. High is rated voltage and the lower speeds just effectively undervolt the motor. Run a typical 1050 RPM 6 pole PSC blower motor on high sometime and measure the voltage from the low tap to neutral, it is usually around 170 volts AC depending on the motor.
There are true 2 speed induction blower motors that are wound as both a 4 pole and a 6 pole. The high and start windings are 4 pole so the motor always starts on high but if it is hooked up as low it switches the power from high to low as it starts using the same centrifugal switch that cuts off the start windings. When not running these motors will show a direct short between the 2 speed wires.

Less airflow allows the evaporator to run colder hence it cools the air more and the leaving air has a lower dew point hence a lower humidity % when warmed back up by the house/building..
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http://www.buildingscience.com/documents/published-articles/pa-ecm-eficiency/at_download/file
Exactly, and this applies to *ANY* type of blower motor

Your idea if "gating" around the coil will cause more resistance to airflow becaise of the right angles, and induced turbulance than just going straight through the coil..... this is assuming that your using a coil that is designed specificaly for that furnace (OEM).

There is no benifit with a 2 speed PSC motor, other than it has 2 speeds, as compared to a single speed PSC motor.

It slows down the air passing the evap coil and allows more moisture to condense on the coils to increase humidity removal.

None of the "new" fractional horsepower motors will last 30 to 40 years anymore, 10 - 15 years is a good lifespan. As a rule, none of them have oil ports for lubrication, and *most* of them have sleeve bearings, not ball bearings.

You don't have a choice anymore.

Your furnace is no more succeptable to lightning or power surges than any other appliance in your home that has a circuit board in it.
Your going to be dragged into the 21st century whether you want to or not. Get over it

This means that your ductwork will have to be checked for correct design and airflow. If your too cheap to pay have it done right, then there *WILL* be consequences, and its going to hit you right in the wallet in the form of failures/repairs, higher utility bills, and lower comfort levels.

Your *STILL* have to have the ductwork and system sized for your home.

This is why you need to get a *competent*, licensed, insured, professionally trained HVAC technician to do the job. One who can and will do the calculations, and take the measurements to insure that everything is correctly sized and operating at peak efficiency............ or you can call "Billy-Joe-Jim-Bob" down the road, or try to DIY. Either way, your going to get what you paid for.
There is a reason that the very best techs do 5 - 7 semester hours a year in continuing education and training. your not *JUST* paying for a guy with a ticket book and a truck, unless your looking for the lowest price.
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wrote:

Needs to be dragged into the twentieth first, before the twenty-first

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Good point.
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yes anyone interested in this subject should read that...
and take note that the study system had the blower running 100% of the time. When the furnace was not heating, the blower ran for circulation. and the ECM motor ran much sloer in circ mode compared to the standard blower so there was much less circulation and not surprisingly less energy was used.
But if you turn the blower OFF when the furnace is off like most real people do, then it is less relevant.
and also note the part where the ECM blower caused gas consumption to increase..
I would say the facts are presented in this paper but the writer slanted the conclusion in favor of the ECM.
Follow the money...
Mark
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Whats obvious is you are doing everything you can to put down Vsdc motors and modern electronics for no good reason. Its future is here, live with it.
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wrote:

transfer - and actually the best air flow as well. Running a squirrel cage fan too fast can actually REDUCE circulation. I think that was also explained in the article. That's also why restricted ducting is such a big deal.

MOST people turn the blower off??? Not up here. Running the blower on low speed keeps temperatures even, and makes the air filter a lot more effective.

That was also explained - and I mentioned that in an earlier thread - the higher efficiency of the blower means more gas is required - but the cost per therm using gas is a lot lower than the cost per therm for electric, so it is still a net saving.

follow. They are neutral, and not funded by manufacturing or marketing companies.

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On Dec 8, 5:53pm, snipped-for-privacy@snyder.on.ca wrote:

I would bet 90%+ of the HVAC installed in the USA runs the blower only when the furnace is heating or the AC is cooling, not 24/7. In a typical house with an unfinished basement or crawl space, I would think running it constantly would be a significant waste of energy from two standpoints. One is that it obviously uses a lot more electricity. Second is that while circulating all that air around you are running it through the basement or crawlspace, attice, etc that is unheated and you are losing heat through the duct work on each pass.
With a properly designed system, I don't see the need for constant circulation.

From the research I've done, I've concluded that the ECM motors are a mixed bag. In a typical house like mine (note that means running it only when heating/cooling), you might save 20% on electricity. I would pay some extra $$ for that. However compared to a regular motor, you have the issue of potentially higher repair cost, ie $700 bills instead of $100 due to the increased cost of the motor as well as the electronics to run it.
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On Thu, 9 Dec 2010 05:42:21 -0800 (PST), snipped-for-privacy@optonline.net wrote:

installations in ontario are set to run the blower on low, constantly. All 3 contractors we contacted for quotes for my daughter's furnace (multi-story condo) strongly recommended it.

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On Thu, 09 Dec 2010 14:27:24 -0500, snipped-for-privacy@snyder.on.ca wrote:

Strange that Canadians do that. Maybe makes sense for that multi-story condo building. Wouldn't make sense for my house. Small 3-bedoom, no "zoned" heating. Though you can "zone" by closing vents and doors to some extent. In some situations a blower always running during heating cycle would work that works - to distribute fireplace heat is one. In my house the thermostat is located in the hallway adjacent to where we spend most of our time - bedrooms, bathroom and kitchen. The dining room and living room are cooler. Maybe a degree or 2. And they are as big as the other rooms combined. This suits us fine.
When we have company and are in the living room/dining room body heat and sometimes cooking heat spilling from the kitchen keeps those rooms comfortable. When it's hot though I have to lower the thermostat to keep those rooms cool. I could reverse all that by moving the thermostat if I wanted to, but it works how it is.
What would happen if my blower was constantly running during heating and cooling times is this. In winter heat would be lost through living/dining room walls and windows, and when the A/C is running heat would be gained through the same. All of this come down to personal tolerance for uneven heat in different rooms, and how much you want to pay.
There's absolutely no question that in my house a constantly running blower would cost me both in electricity and natural gas. Because it would move heat or cool air to places it's not needed. I used to argue with my wife all the time about heating and cooling. She can't take it cool in the winter, or warm in the summer. I gave up the argument. You got to know when to fold 'em. But I never even started an argument with the laws of thermo dynamics, and don't intend to.
BTW, this reminds me how car A/C compressors kick in on defrost mode. I used to pull the A/C plug when winter rolled around because I never had a problem defrosting with just undried hot air and didn't wait to waste a couple/few HP all winter just to blow dried air on the windshield. I stopped that when I heard the compressor seals could suffer from disuse, but mostly because I lost my "need for speed."
--Vic
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On Thu, 09 Dec 2010 14:51:36 -0600, Vic Smith

in my house - a 2 story with finished basement and no doors between floors. The house is quite well insulated, but the upstairs is still cooler than the main floor, and the basement is very comfortable year round.With the blower running on low constantly we do not get condensation on the patio door on extreme cold days like we did without the blower running, (RH is steady at about 35%) (one register is at the corner of the door)
My daughter's place is a 6 level split, basement, entry, living room, kitchen/dining, 2 BR and bath, and master bedroom. Built like a ruddy silo - definitely no place for old men!!!! We just insulated the basement and attic, and right now, with temps down to -17, the only cool area is the entry level (built on concrete slab - 3 outside walls)
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snipped-for-privacy@snyder.on.ca improperly and unnecessarily full-quoted:

Look - I live in Ontario too. And I just got dumped on with 3 feet of snow, and it's like 16 to 24 F around here lately.
I live in a drafty 1976-era house. I can tell you that there is no reason to run the blower constantly in the winter. When I switch my HVAC from summer to winter mode, the only time my blower fan comes on is when the furnace is on. There is just no need for a constant breeze inside your house in the winter.
Running the fan constantly in the winter, even at a low speed, is not efficient from a heating point of view. By keeping a constant breeze, you're helping interior heat loss by causing interior air to constantly come into contact with your walls and windows, which are the coolest parts of the interior and from which heat is transfered out of your house. When the fan is off and there's no air circulation, a temperature gradient will set up in the air near the surface of the walls and that air will be cold but you won't get as much heat loss through this gradient as you would if the air was constantly mixing.
In the summer (late may to maybe late september) yes my fan is on quite a bit, and even if I had a low-speed option I would not use it - I would still be using the normal hi-speed mode for circulation and comfort.
And I still say that having the ability to draw return air totally from a dedicated outside duct in the summer and force the normal return air out of the house through another duct is more energy-efficient at cooling your house vs using an AC during those times when the outside air temp is lower than the current inside air temp, which frequently happens in the late afternoon and evening in the spring and late summer.
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I totally agee with that. Probably isn't done because of issues with ducting to the outside. For my basement furnace it wold take a up window, not counting the ductwork and diverters. So we open the windows when it's cooler outside than in. But if there's no breeze you really need fans in the windows to make that work well.
--Vic
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I'd say it depends on how much cooler the outside air is. And even then, you have the issue of humidity which is a major concern in many climates. Pulling humid air from outside that happens to be 5 deg cooler than the house inside wouldn't seem to make a lot of sense to me. And here in the NYC area, the few days of the year you would do that, ie some Spring and early Fall days, it just isn't worth it comared to the addional ducting. Besides, I thought Home Guy was all about simplicity. At a minimum such a system would require actuators, more controls, etc. To do it right you'd have to measure outside temp, outside humidity, inside temp, inside humidity and then have a mircrocontroller decide what to do. Sounds exactly like the complexity that HG wants to rip out of a new high efficiency furnace.
If you want to go that route, a whole house fan to pull air in from outside is an option. But it too has the above problems and being in the upstairs ceiling/attic interface, you now have something difficult to seal and insulate perfectly for the entire winter. Meaning what you gain in a few days that you use it could be more than lost.
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On Fri, 10 Dec 2010 03:57:10 -0800 (PST), snipped-for-privacy@optonline.net wrote:

You don't need microcontrollers. Just go to the basement and pull a lever or crank on a chain fall (-: Where I live, and the house I live in, it makes sense to draw in outside air at night about 10-30 days a year, depending. My house is brick, with little or no insulation. Haven't torn off any drywall on the exterior walls, but I know from drilling the drywall is on furring, maybe 1", not 2x4's. Never picked up any fluff when drilling. Surprisingly, my gas bill isn't bad. But it can absorb a lot of heat during the days of high sun and the heat migrates in if the nights aren't sufficiently cool. Better to have the night air working on both sides. Adds up to 10-30 days a year, depending. The same was true of my last brick house. Besides, if it's not too humid, outside air is good.
--Vic
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On 12/10/2010 8:03 AM, Vic Smith wrote:

I've rented old buildings in the past that had an interesting hollow tile like building block construction for the walls. The material looks like the red roof tiles and with no heat in the warehouse area, the temperature never got into the low 30° range, nothing ever froze. I don't know what the material is but it seems like the designers knew what they were doing around the turn of the last century. :-)
TDD
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On Fri, 10 Dec 2010 08:03:57 -0600, Vic Smith

to draw in the outside air, the humidity is way too high to make it an acceptable alternative most days.

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snipped-for-privacy@snyder.on.ca followed incorrect usenet style by full-quoting:

Down here in south-western ontario that is not usually the case.
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"ON THE DAYS WHEN YOU REALLY NEED IT"
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snipped-for-privacy@optonline.net wrote:

Some systems for commercial buildings do use all outside air when economical. They need, if I remember right, 10% outside air when occupied in any case. Makes it more practical to go to 100%. Duct control is with "damper motors".
They don't just use outside temperature. They likely use an "enthalpy" controller, which combines temperature and humidity. If you don't take in air with humidity that is too high you don't have to worry about inside humidity, and control on temperature. One I remember had a temperature "set point" control in the supply air duct, that was a potentiometer output, which connected to the damper motor that controlled the amount of outside air that came in.
--
bud--

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