Hi,
I have just moved into a house about 40 years old. Very nice condition and was a good buy. There anyway to modify the fan motor so when heat or air is required will torque up to a higher RPM.
I had this in my previous house and it was great. I admit I have not done too much research on the motor, so this question is just for feelers and help.
Thanks.
Jeff
There are a couple of nice HVAC guys in this group and several who are not.
I am not one of either group.
It may be possible if you have a multi-speed motor. For anyone to help you is going to require more information. I suggest you post again with the brand name and model number of the furnace. A guy with the nick of Turtle is one of the nice guys.
Colbyt
Yes, there is, but ... you have to do so with knowledge of what you're doing. The pulley sizes can be modified (assuming it's not a direct drive type) to increase the speed of the fan, but the motor must be able to handle the added load. It's also possible that the belts, assuming there are belts, are too worn or even the wrong width to ride properly in the pulleys. Some pulleys are even adjustable in size. But, add too much load and you'll be looking for another motor, so step carefully and listen to any experts that may chime in here.
Regards,
Pop
The standard air flow rate is 400 CFM / ton for cooling and whatever the heating (furnace or resistive heat) manufacturer recommends for heating. Don't go messing with this unless you know what you are doing.
Jeff,
Your question is a bit confusing. Most of us are assuming that you are asking if you can have two different fan speeds - one lower speed for heating and a higher speed for AC. If so, then the answer is "usually." Many fan motors have multiple taps for multiple speeds and it is pretty easy to determine how to change those taps IF you know what you are doing. If not, then get some advice from somebody who has done this many times or integrate this simple modification with a routine service call for HVAC maintenance. The pro shouldn't charge you too much extra to "rewire" the motor as long as he is already out to your home for the annual maintenance call.
Also, many tract home developments built around 40 years ago had the same furnace, AC and ductwork in most of the homes. If you locate a neighbor with the same setup as yours, then you can check out which taps are being used on his fan. This isn't 100% guaranteed, but it is usually safe. Many of us could make a good educated guess on which taps and fan speeds should be used, but I'm not going to make that blind suggestion over a newsgroup.
Final comment: Be certain that whoever pulls out that fan/blower assembly cleans the squirrel cage if needed and lubes the motor. Fins on the squirrel cage can get clogged with dust, especially if the home has every had an electronic air filter which was neglected. Also, some motors are difficult to lube and some HVAC guys skip one or both oil ports on the motor.
Good luck, Gideon
You can adversely affect your system's performance as well as indoor comfort by injudiciously changing the blower speed. Motors that have multiple speed taps are designed to allow for maximizing performance and/or to allow the same motor to be used for multiple applications. Increased blower speed will result in less effective air filtration and greater air noise.
hvacrmedic
I admit I have not done
Since you mention AC, I should guess that the furnace system has both heat and AC?
In this case, typically the AC is set to the highest blower power. But not always. You do have a local HVAC guy who services your system?
This probably came up beforebut I still am not sure of the answer. My AC condenser is exposed to the sun for a good part of the day. I have often thought that by making some sort of a covering to ward off the sun the unit would cool better and perhaps not work as hard.Any ideas? Frank
The cost of any cover will be more than any return you will see in efficiency. Plus you want the AC to be in the open as much as possible to get good air flow around and above the unit. Good chance a roof over it would block the air flow enough to be counter productive! Leave it alone! Greg
No ideas off the top of my head, but ... yes, getting the sun off an air conditioner will make it work better and more effieicntly. The trick though is not to block any air flow. It varies from unit to unit, but it can be done. I had some noticeable luck and a measured increse in the cooled air temp of a few degrees just by putting mirror-film on the case of one of mine, a 10k btu unit. Since the western sun hits it both from the top and the west-side directly it was hard to figure any way to get the sun off it without stopping some air flow. The tree I finally planted does a great job now, after only a few years. BTW, it only took the film idea a few weeks to get so dirty it didn't reflect anymore so it's not a good answer. I suppose there are ways to do it with properly positioned louvres but that's beyond my abilities . The tree worked best in the long run, for me at least. Also shades part of the hosue of course.
HTH
Pop
No...wont make any difference you will ever see. Want proof? Just look at the millions of units in CA, NV etc that are installed on rooftops....and yes, I started working in the deserts of CA in HVAC, and I can promise you, the units are designed to be outside, in the sun...and work.
Then there is the effect that the condenser is buried in the housing, not being hit directly by the sun. As soon as the unit kicks on (or very soon thereafter) the interior of that housing is going to be at the ambient air temp anyhow. The heat exchangers (radiators) will also reach operating temperature whether the sun hits them or not.
Harry K
This is Turtle
This question has been ask at least a 100 times that i know of and here is what was said just about everytime.
The HVAC People and some manufactors say it makes very little difference as to sun hitting it or not. Now when they say that it is on the thought that it will run just fine but at a little higher head pressure which will cost a little bit more to operate the system. This will come from the ground, unit, and area around the unit will be heated up and will be putting off heat to be sucked into the condenser coil which will be a little higher temperature than if it was setting in the shade. Now this small amount of added heat is small but may not justify any cost to build a shade cover for it but shading may not be cost effective but it does save a little money to shade it.
I researched it over the internet and came up with a few good sights that said it saved money but none said how much. Now here is one from the Florida Public Service Commision on 101 ways to save on your electric bill. Check out Artical number 53 to see about condenser in the sun.
You don't need any research.
Just put your clamp-on ammeter on the compressor, and hold up a big sheet of something lightweight to turn the shade on and off. Does it register anything on the meter when you do so?
Would like to hear your results.
Not likely. The AC is looking for Air temp and that is not going to be much different with or without shade. In fact if the shade reduces the air flow, it will increase operating expense.
This is Turtle.
Hummmm , I will try this in the next day or two while working on the systems. I'll get back to you.
TURTLE
My understanding of things, shade is cooler. However, I've seen one study where they did one test (two houses, one in the shade) and found less than
5% savings.I'd go wtih the shade, as long as it isn't blocking the air flow.
I'm guessing with as large a mass, it would take an hour or so to make any readable difference.
Instantaneous current mesurement isn't the answer. When the compressor is running, it always requires the same power. But maybe it will run less often to keep the set point...
Watt hour meter is the required device to compare for example, two similar weeks temperature.
Frank
HomeOwnersHub website is not affiliated with any of the manufacturers or service providers discussed here. All logos and trade names are the property of their respective owners.