Through floor ventilation.

[ts39136]

Hello All,

I spent yesterday re-thinking our wintertime ventilation situation. After much research and amazement at the cost of things, I found a new fan at WalMart for $12. It is a high velocity (high speed), 9-inch fan with aluminum blades. I took it apart and made a shroud for it. It will mount on the ceiling with only the back grate sticking out. It will replace out the two computer fans that I now have powering air through 8" flexible ducting to the upstairs. The computer fans have been very reliable (rated at 5000hrs) and have ran for three winters full-time from cold-snap to spring-frost. I'm guessing they have run for 12,000 hrs or better without a single squeak. I'm hoping that this new fan will last just as well if I keep it oiled.

I was hoping to be able to balance the fan by putting bits of solder on it, but it's proven a difficult task because the center of gravity if in front of the axle. I cannot find a way to string it up. I did readjust the pitch of the blades and got them all into line with each other. There is still some vibration present at super-high speed.

Last night I thought. The fan is mounted on a 12" by 12" frame. I will place this frame inside a 13" or 14" frame that is mounted on the ceiling. I will attach the fan frame to the mounting frame with strips of fiber reinforced rubber strips (army surplus). I thought I if I used rubber all the way around, it would transmit too many vibrations, so I think I'm going to use old bed-sheet strips to fill in the gap and paint the strips with latex to seal in the air.

I'm also going to rework the ducting for smoother flow. I'm hoping to get 200cfm with 70 watts instead of the current 80cfm with 44 watts. The overall objective is to keep the downstairs cooler while burning a greater percentage of firewood to pellets.We'll see.

EDIT -- I finished the duct fan. It came out really nice. No vibration transferred to the house at all. It will look better once I trim the fabric and paint it white (including the grille). The fiber reinforced rubber was too sturdy (military surplus, huh.)! I had to cut strips, then cut a "Z" in them to get enough flexibility. I also reworked the distribution box in the upstairs closet. I used cardboard and duct tape to coerce the air towards the grille. I also bent the fins on the grille to keep the air traveling down the hallway better. WHAT A DIFFERENCE!! Before, I could barely feel the air moving. Now, It feels like you are sitting in front of a fan, go figure. I estimate at least triple the flow and only twice the wattage. I am going to buy a spare fan tonight; $12 is cheap insurance.

 

[Beefie]

Keep us posted on how long the walmart fan lasts. . Hope it works out . I think you might have it nailed on vibration.

Beefie

 

[ts39136]

My daughter has a similarly built fan (AC to DC with built in transformer) that has been running non-stop for 3 1/2 years. It has LED lights that make designs and she has grown rather attatched to it. I had to tear it down once and remove dust from the shaft and reoil everything, but it's still running strong.

My worry is that the bushings are not designed to hold a vertical load. I tried to turn the fan blades over to give the shaft some lift, but design prevented me from doing that. We'll see.

 

[RCR 3 EVER]

Axial box fans

Last year I bought 3 axial box fans rated at 230 cfm, 115 AC, .23 Amps.
I tried them for our new fireplace to transfer the heat from living room and kitchen areas. I had thought that using a hi CFM fan would actually "feel" too cool instead of just transferring the heat to another area. I was able to actually transfer the heat to the basement using the 2 fans 1 fan at top of stairs and 1 fan at base. Our house is a 1,100 sq.ft. ranch with a unfinished basement and fireplace in Living room. I used another fan to transfer the heat from Living room to other end of house where our bedrooms are.

Basement did not get much heat since it is difficult to pump heat down but we did get rid of some of the excess heat in Kitchen. Living room and bedrooms were very comfortable and walking in front of the fans did not feel as if you were cooled down. It was more of a warm breeze being pushed by the fans.

Foer experimentation I tried higher capacity fans and they just seemed to cool the area in front of where the fans were placed by the breeze.

I just have to remove the extension cords and set up switches instead for the fans now that I have locations in mind.

 

[ts39136]

That would be hard to pull hot air downstairs. In my case I'm trying to pull COLD air downstairs to cool the living area of the room and the adjacent bedroom. The duct is very close to the stove and it pulls right off the ceiling. I have a non contact thermometer that says the air it is pulling is sometimes 120 degrees! Too hot.

If I leave the fan off, it acts as a cold sump, but it doesn't help to cool the livable area.

Here is a picture, don't really know how much good it does, but it sure was fun to make.

 

[JAM]

I use a couple of bathroom vent fans to pull cold air out of the basement through the dead space behind the fireplace to heat it and then out into the living room. this works pretty good pulling the air from the kitchen into the laundry room before recirculating across the basement. The fans are mounted to wood boxes with weatherstrip foam gaskets to deaden vibration. The only part visible from the living room are the grills over the fans.

 

[RCR 3 EVER]

Although not as efficient to run we can also use the old 1998 furnace fan system, We have doubled up the size of the cold air return grill opening at ceiling in Living room to 32"x16", this opening is approx 8' from the furnace. We then put pieces of magnetic sheets over some of the other returns to cover only about 1/4 opening in other rooms. We also closed heat vents to rooms except non accessible baths. We then opened up all vents in basement. We normally keep the vents closed in Summer.
Since our aim is NOT to use furnace for heat we have to get the heat to basement somehow from the kitchen which was stifling and at head of stairs to basement. Our plumbing system pipes can't freeze but our freezers will run cheaper though

Gravity air vents off the fireplace are very efficient along with the fan. The 8' ceiling temps got get as high 150 at times and I am 6'6" tall so no decapitating fans for me. Amazingly those little box fans did help but I needed 2 fans in the stairway.

 

[paladin]

I heat my whole house with two household fans. I put them on timers so they will run just when the burner is making good heat then they will shut off. My burners in the basement and it pulls heat up stairs. The older fans are better they are lower speed but move alot of air slower.

 

[ts39136]

I use a couple of bathroom vent fans to pull cold air out of the basement through the dead space behind the fireplace to heat it and then out into the living room. this works pretty good pulling the air from the kitchen into the laundry room before recirculating across the basement. The fans are mounted to wood boxes with weatherstrip foam gaskets to deaden vibration. The only part visible from the living room are the grills over the fans.

I really like the bathroom vent idea, but the ones I could find that had enough flow were $180 or so. Too much for me, I'd rather save for a new chainsaw or a rangefinder.

It would be have been really nice to have the living room right above the stove, too. Wonder how hard it could be....

 

[Straightgrain]

Great idea, I run horizontal ducts/fans (one story house).

Whatever my opinion is worth......What bugs me about some fans between floors is that it makes a place to allow fire and smoke to spread very rapidly. Floors with 5/8" gypsum below have a 20-30 minute fire resistive rating in that membrane/assembly.

The beauty of today's interconected fire/smoke/co2 detections sysytems is they can be interlocked so that the fan would shut down and the dampers would cose (slowing the pennitration of heat and poisonous gases to the upper floors) (ruskin is a brand name) if there was an unexpected external fire or leak. unchecked air from a solid wood buring appliance is very dangerous.

 

[RCR 3 EVER]

Firer dampers -automatic

Great idea, I run horizontal ducts/fans (one story house).

Whatever my opinion is worth......What bugs me about some fans between floors is that it makes a place to allow fire and smoke to spread very rapidly. Floors with 5/8" gypsum below have a 20-30 minute fire resistive rating in that membrane/assembly.

The beauty of today's interconected fire/smoke/co2 detections sysytems is they can be interlocked so that the fan would shut down and the dampers would cose (slowing the pennitration of heat and poisonous gases to the upper floors) (ruskin is a brand name) if there was an unexpected external fire or leak. unchecked air from a solid wood buring appliance is very dangerous.

There are also fire dampers in low pressure systems, they have a fusible link that closes automatically at 165 degrees

 

[JAM]

I really like the bathroom vent idea, but the ones I could find that had enough flow were $180 or so. Too much for me, I'd rather save for a new chainsaw or a rangefinder.

It would be have been really nice to have the living room right above the stove, too. Wonder how hard it could be....

I got mine from a BIL who was doing a remodel for free, The price kinda helped with the acquisition

 

[ts39136]

I heat my whole house with two household fans. I put them on timers so they will run just when the burner is making good heat then they will shut off. My burners in the basement and it pulls heat up stairs. The older fans are better they are lower speed but move alot of air slower.

Instead of a timer, I bought a "thermocube". It's a really simple thermostat. I bought one that turns on at 77 or so and off at 70 or so. CHEAP - $14!

 

[Straightgrain]

Way to go on the thermocouple, I run one on the flood lamp down in the well house. I drilled a little peep hole so I can see if the light is on from the house.

Is the fan quiet?

 

[ts39136]

Way to go on the thermocouple, I run one on the flood lamp down in the well house. I drilled a little peep hole so I can see if the light is on from the house.

Is the fan quiet?

Yes, as can be expected, I guess. On medium speed its quieter than the two computer fans. On high speed it's about the same.

We have a thermocube in our well-house too.

 

[ts39136]

Well, I turned off the cieling fan today. It's been running since mid october without a hitch. I might put a drop of oil on it before next season. I never ended up using a thermocube.

This made a HUGE difference this year. The downstairs was only a few degrees warmer than the rest of the house.

When sitting about 10 feet away it just sounds like a moderate breeze and I can't even hear any "mechanical" sounds.

Almost firewood gathering time... I even got to fire up the 210 for a little yard work. I'm glad I sharpened it before I put it away. What a joy... spring is almost here!

 

[Beefie]

I am glad to here that it worked out. It should be interesting to see how many years of ues you get out of that fan.


Beefie