Ceiling fan helpful?

Create a Post
Tommy P

Tommy P

MGF, Master Grumble Framer
Joined
Nov 16, 2003
Posts
870
Loc
Mid North Indiana
We have them at home and have always thought they helped with heating and cooling. Especially with moving the warmer air up by the ceiling down to the rest of the area. The winter season here in northern Indiana really makes the furnace run at the business! So I'm trying to combat the rising natural gas price coming this season. Our ceiling height is 10'. Of course when I change any light bulbs I'm always amazed at how much heat is up at the ceiling.

I'd like to push some of that wasted energy (and money!) down where we can get some added benefit.

Has anyone else invested in fans for your business space and do you feel they were worth the money spent? I figure I could use about four of them for a total cost of 400 - 500 bucks. I can install them myself.
 
I've had ceiling fans in two different stores and found them in both to be highly beneficial in both winter and summer. The first store we had 14' high ceilings and the second 22'. In the store with the 22' ceilings we had 300 watt high pressure sodium lights and 1000 watt metal halide lights. Believe me...these lamps give off a lot of heat!

Currently my ceilings are only10' with a drop ceiling and flourescent lighting. I don't believe in this scenario I would benefit that much from ceiling fans and they could cause a hazard.
 
Dave said:
....Currently my ceilings are only10' with a drop ceiling and flourescent lighting. I don't believe in this scenario I would benefit that much from ceiling fans and they could cause a hazard.
Click to expand...

I agree with Dave on this issue. We've had 3 ceiling fans in our shop since the mid 1980's and have used them ONLY on occasion. They really have minimal benefit in our 10 ft ceiling situation.

With higher ceilings, I could see them helping.


Now installing an exhaust fan with a thermostat above the lowered ceiling to draw out trapped warm air in the summer is another thought!

John
 
Wow, so you two really don't think adding fans to a 10' ceiling does much? When I change bulbs I bet there is a twenty degree difference up there!

And as far as danger goes Dave......just how tall are you?
 
watch out for oversize pieces..frames and ceiling fans don't mix...I know from experience!!!
 
Oh,and if you are playing with gold leaf(or the "fake stuff") do turn off the fan....NO,don`t ask! :D L.
 
Baer Charlton said:
Mary, I had to look up........ clockwise for down draft.
Click to expand...

Dislexia.... if you look UP at the fan, it will be running counter clockwise... which is the normal direction of the motors..... and most people just leave them that way. That way in the summer you get the cooling moving air, and in the winter you get that breeze of heated air.
 
In a former life I engineered ventilation systems for factories -- not exactly the same, but similar principles.

Ceiling fans will equalize the temperatures from floor to ceiling. That means "stratification" of the air -- warm up, cool down -- would be eliminated. That also means the thermostat would react to the average temperature in the room, and would not be calling for heat when there is heat at the ceiling. No question about it; ceiling fans are proven to save on heating and cooling costs. Usually the payback is about two heating seasons, if the installation is done right.

The direction of the fan will not matter, other than the comfort factor. If the air blows down from the fan, it will circulate up along the walls. That makes wind under the fan. If the air blows up from the fan, it will circulate down along the walls. That makes wind along the walls. Either way, the anti-stratification benefit is working for you. Take your pick.
 
Thanks for the advice.....
I'm going to give them a shot. Wasted money before on stuff that made less sense.
 
I have them in my shop, one in the front and one in the back. They do help with circulating the air, whether it be warm or cool. If you put one in the back room and you cut length moulding just remember to turn it off when you pull out big sticks, or you will have little sticks!
 
Our shop has 18 ft ceilings .... I wish we had fans that would move the air around a bit better then the floor fans that sound like small jet engines. How annoying.
 
freakquency said:
Our shop has 18 ft ceilings .... I wish we had fans that would move the air around a bit better then the floor fans that sound like small jet engines. How annoying.
Click to expand...

I guess you use the floor fans because people have complained about the need to move air? The person who makes the money decisions may be excited to learn that ceiling fans can move more air more effectively, they are almost silent, and their operating cost is much less than that of high-speed fans. Since they're off the floor and on the ceiling, they're completely out of the way.
 
tool man Tim will soup up your fan motors so they will work with high ceilings....but be careful..too much power will take the roof airbourne and suck everything out of the shop.
 
what a timely subject...i just called a contractor to install a ceiling fan in my home to equalize temperatures between upstairs and downstairs.

in our stairway above the landing (7 steps up, then landing, then 7 more steps), we're replacing light with fan/light. One of our 2 intake vents also happens to be near the ceiling and light in this stairway.

up till now, we've opened and closed vents strategically too minimize excessive heat upstairs in winter and and not enough a/c upstairs.

will a fan in our stairway help??
 
froptop said:
...we've opened and closed vents strategically too minimize excessive heat upstairs in winter and and not enough a/c upstairs.

will a fan in our stairway help??
Click to expand...

It might, but you may have an inherent problem with your HVAC (Heating, Ventilating, Air Conditioning) system.

Warm air naturally rises, so the upstairs would tend to be warmer than downstairs. The way to avoid that uncomfortable and inefficient air stratification is to circulate the air. How the air circulates is important. HVAC systems are generally designed to move enough cubic feet of air per minute (CFM) to eliminate stratification. That requires a certain CFM capacity in the furnace blower, and in the structure's connected ductwork. If your system is moving too few cubic feet per minute, it would be difficult to compensate for that deficiency.

If your HVAC system is inadequate to move the necessary cubic feet per minute through its ductwork, ceiling fans could be a partial solution for specific rooms of the structure. A better solution might be to move more air through the ducts by increasing the air-moving capacity of your furnace blower.

Some experts recommend running the furnace blower continuously in order to keep air moving throughout the structure. That is especially helpful if an electrostatic air cleaner is used to remove airborne contaminants that contribute to allergies -- it works only when the air is moving.

A dirty air filter; closed, covered, or dirty ducts; or anything else that restricts the movement of air could foul an otherwise-adequate HVAC system.
 
In SoCal we had a 24' ceiling and put a fan/light for the same hot air pocket during the summer. We ran the fan in the "up" position to disperse the air across the great room then down the walls.
If you just have a stair well, "down" and medium would be my suggestion. It will be quiet, and create a moving "air dam" in the stairwell.
 
Baer Charlton said:
... It will be quiet, and create a moving "air dam" in the stairwell.
Click to expand...

Such an "air dam" would tend to divide the air flow between the two floors, but it might not eliminate the temperature difference upstairs vs. downstairs.

If you shut off the upstairs registers, then the upstairs cold-air returns would either draw warm air from downstairs or, if you create an effective "air dam" in the stairwell as Baer suggests, the cold-air returns upstairs could not function in the circulation of air in the structure.

A fundamental fact is that when air (or water) is to be moved, it must have a place to come from, and a place to go; cubic feet in, and cubic feet out. If you remove air from a space without a free-flowing source, you create a vacuum. If you put air into a space without a place for it to go, you pressurize it.

That bit of natural physics is important. For example, if you installed a powerful whole-house fan and sucked air out of the house through a roof vent, it would be important to open windows to allow air into the house. If you leave the windows closed, the house would become pressurized (depending on how tightly it is sealed) and the fan motor would be overloaded.
 
Jim Miller said:
If you leave the windows closed, the house would become pressurized (depending on how tightly it is sealed) and the fan motor would be overloaded.
Click to expand...


Actually, the fan would become LESS loaded. If you ever put your hand over the end of a vacuum cleaner you will notice that the RPM instantly skyrockets. The reason that happens is because no air is moving, which decreases the resistance and allows the motor to run closer to its unloaded speed. It seems backwards, and I think it's because we are familiar with governor controlled gasoline motors that increase power upon resistance.

However, we can seen this principle quite visually with our shavings collection fan because we have a Variable Frequency Drive (VFD) controlling it. A VFD is a computer that controls motor speed by manipulating the frequency that is fed to the motor. Without going into all the details of how it works and what you can use it for, the bottom line is that it has a digital display of the amperage draw. We leave our set to the same frequency (which equates to RPM), so the only change is the amount of air flow. If all the collection pipes are closed the amperage is maybe 35, whereas with them all open it will go up to as much as 55.

If you don't believe me, find an electrician with a clamp-on amperage meter and hook it up to your vacuum. I guarantee that you will see the amperage drop (which means less load and less energy consumption) as you put your hand over the end.

Now you may be wondering that if that's the case, how can a vacuum pump even work. The fact is that vacuum pumps do not use fans, so the principles are entirely different. Not merely comparing apples and oranges, more like apples and cashews...

If you're interested in more scientific or in-depth reading, do a search for "fan laws".
 
We have 14' ceilings in our store and have 6 ceiling fans, and have for probably over 20 years. We actually benefit from them more in the winter than the summer. Because it's so warm near the ceiling the fans bring the warm air down in the winter and help ease the load on the furnaces. In the summer we have a problem because the fans bring the warm air down to the air space we work. Sometimes I'm inclined to shut the ceiling fans off during the summer and use floor fans.
 
David N Waldmann said:
Actually, the fan would become LESS loaded.
Click to expand...

Thanks Dave, simpler you can go make a blended drink. If the slurry stops moving, the blade is turning in just juice the RPMs ramp up; as soon as the ice breaks up and hits the fan as it were.... the RPMs grind down into the lower band width.

Jim, the air dam is an important tool for separating two air conditioned levels or areas; but only works where each section or level has delivery and return separate from the stairwell.

But then when you're trying to retro-fit an 80 year old house with modern delivery and recovery... it becomes a whole different ball game. Next time, I'm switching to a water furnace and hot water space heaters. :icon11:
 
Create a Post
Back
Top