Light Dimmer powering blower/squirrel cage?

[Opcom]

.

[W1VD]

T

Instead of paint consider 'Stove Black'. Comes in various packaging and by various names. Does a good job of 'coloring' rust black and slowing down it's progress. Kinda like shoe polish for steel/cast iron stoves. Apply it every couple years where needed.

[WA1GFZ]

stove black works great. Kind of like VHT header paint
Rustolium makes a good product I have been spraying on the underside of my truck. It turns surface rust black. Home chepo sells it. I wouldn't use it on a hot surface though

[K1JJ]

T

Instead of paint consider 'Stove Black'. Comes in various packaging and by various names. Does a good job of 'coloring' rust black and slowing down it's progress. Kinda like shoe polish for steel/cast iron stoves. Apply it every couple years where needed.

Good suggestion, Jay. I wasn't keen on painting the stove anyway cuz of the potential problems of prepwork, break-in smell, etc.  This black stove polish looks perfect for the job. TrueValue Hardware has it:

http://www.idealtruevalue.com/servlet/the-41767/Detail

BTW, I have some brickwork the stove will sit on that needs some serious cleaning after 15 years of stove abuse.  What product or method should I use?  It's in the house over a wood floor, so sand blasting or soaking with a liquid might be a problem, unless it requires small amounts of liquid so not to drain thru the cracks. I thought some kind of acid was used with a stiff brush?

Opcom:  Thanks for the info on the various controllers. I'm still looking and deciding what to use.

T

[KA2QFX]

Tom,
 LOL! Funny you should ask about this topic. I just got flamed by a couple or morons on another board regarding dimmers and inductive loads.  Suffice to say the other posters are correct here, it's not a recommended way to go.

I have often reduced/adjusted the speed of small fans and blowers with a series capacitor. They don't dissipate any significant energy and don't get the motor hot. Depending on the impedance and load of you motor you may have to try quite a few values. 300 to 600 volt, polys in the 1-2uF range, or less, usually do it the average 120 VAC muffin fan.

[K1JJ]

Thanks for the suggestion, Mark.

I will try clip leading in a few capacitor values and see if I can get the two fan speeds in the ballpark.  At full speed they are too noisy and blow too much air anyway.  Hopefully I can find lower settings that are good and will start up - and leave it alone. The variable controls will be my second choice, but will cost $50+ to do.


T

[KB2WIG]

 " Nice old buzzard stove!  I'll bet that's a 90K BTU from the looks. It's almost looks bronze? "

The Gay uta-Andes apears to be cast iron. The construction has a 'firebox' base, front doors and vent and a top, all apear to be cast iron. The center, or cylinder part is sheet metal, probably steel, I donta know. Its thin compared to the casting..... The 'skirts' are removeable. They are chromed, along with the nameplate you see in the picture. The crome is showing some rust; thats the 'brass' look. The top thing is removabel, so you can put your coffee pot or frying pan on it. The thingie is just a ornament although it would help to radiate heat from the top..... 

gottra get the chimbeley sweep in to check the stack.....



klc

[W7SOE]

Oh BTW, be safe and install a CO detector down there.  Prevents the permanent nap....

73

Rich

[KB2WIG]

Oh BTW, be safe and install a CO detector down there.  Prevents the permanent nap....

73

Rich

I've played the game and puked till i bled.... just a little Code violation. Natural gas water heater vented into a unlined bric chimbley.... the brick dust, soot, bird crap buried the exhaust and nearly killed all of us. Funny how them little rules have a meaning.


klc

[Opcom]

Be sure to post up how the series cap works.

[w4bfs]

Does anyone have experience using a standard 120VAC light dimmer to power a blower/squirrel cage fan?  I wonder about start-up load stress and longevity.  I'm looking at 150-200 CFM size blowers - not all that big.

I use Variacs now for the rigs, but want to add a few blowers around the house to circulate warm air from the coal stove and use the cheaper, easy-to-install dimmers to ramp down the fans at times.

Anyone doing this now?

T

hi Tom ... seems like the cheapie wall dimmers don't like highly inductive loads so the question becomes just how much resistive (acting) load do you put in series or parallel to tame the critters ...an experiment to try would be to put a 100 Watt incadescent lamp in parallel with the fan ... iffin I can find some time I will try ....be willing to bet ittl werk

******* ....the next day .... *******

did a quick test using a $5 rotary dial chinese dimmer .... instruction paper said incad or halogen NO motors, transformers, lids or space cadets ...40 w min load if you prease ... the resistive load is a 60 W incad bulb and I paralled 2 diff centrifugal fans and tested

fan #1 is small (approx 2 1/2 " impeller) shaded pole motor with nameplate draw of .17 Amp

fan #2 is medium size (approx 4 " impeller) shaded pole motor with nameplate draw of .37 Amp
(out of Henry 2K amp)

while running into the lamp dimmed somewhat I added the fan with clip leads and the dimmed lamp brilliance remained unchanged and either fan ran quietly at reduced speed ... connecting/unconnecting the fan did not change lamp indication ... ran this for 15 min ...dimmer box didn't even warm up any that I could tell

so I guess that it can work .... I suppose that an inductive power factor limit should be determined

[Rob K2CU]

Tom,

If you build an outside bin, be sure it is well covered and protected from snow/rain/ice. Back in the mid nineties, Baltimore suffered from power outages during one winter cold spell, because the giant mounds of coal for their municipal power generators froze solid. Granted it was sub zero weather.

When I was a kid, we would visit my grandparents in Queens, NY and they had a "basement" under their back porch that was actually an old coal bin, then no longer used. There was a loading chute opening outside and a small access door in the basement near the furnace, which had been replaced with a gas fired furnace. My brother an I pretended that the bin was a dungeon!

[Ed/KB1HYS]

Coal bins were typically built in the basement for a lot of reasons:
Easy ramp style filling from the truck.
Close to the point of use, just across the basement.
Keeping the weather out of the coal, and keeping the operator out of the weather. Who wants to leave the house when it's -15 outside to shovel some coal into the bin? 

I ran a coal stove some years ago. Reliable and put out good heat. No problems with ash, but we burned anthracite, lump coal. Poor coal forms lots of ash and clinkers (lumps of nonburning material that can clog up the grates, black sand or some such I think that gets fuzed by the heat). A small shovel and an iron rod bent into a hook shape with abit of a point. Use the shovel to fill, and the rod to rake, bank, and break up clinkers if needed. That thing only when out once, and I was not really that reliable at filling it.  I'd usually put in a good bit before bed, bank it up and set the damper.  We didn't have a bin in that place, but would have a pile dumped in the drive and would load up a bunch of old 5-gallon pails.  Kept a pail in the room near the stove, the others could be kept anywhere with the lids on and stacked etc.  I'd have rather had a bin but it wasn't my house.

[WA1GFZ]

Yes an rod about 3 feet long bent into about 4 to 5 inch L is great for clearing grate. When you burn good coal you will never need it.
My first couple years I burned crap and used it every day.

[K1JJ]

OK the bin info, etc.  I guess most older stoves/furnaces were in the cellar, so a good idea to have the bin there too. In my case, the stove is on the main floor, above the celllar, so an outside bin would be the shortest trip and less gravity to fight.  Good point on the coal icing.

Well, I moved the old 400 pound stove outside and brought the new 550 pounder in and put it up on a 18" pedestal. Did it myself - with a good dolly and rolling engine hoist it was a piece of cake...  

The stove itself has a blower that moves air thru the body. That, coupled with the two blowers pushing air to the adjoining rooms should be a great system. Can't wait to try it out this season.

I'll key an eye on the coal klinkers, Frank. I got the coal with the deal, so pot luck.

Think I'll make up an "L" rod like you guys suggested - thanks.

I might take a phoro of the installation once the bricks are cleaned up.

T

[w1vtp]

My coal bin was in the corner of the basement (my former QTH).  It was next to a cellar window that I could open and shovel the coal from my pickup right into the window.  In the basement, I had a opening about a foot wide going from the floor to the top of the bin with slots for several pieces of plywood with handles on 'em.  I had stops about 6" from the floor so the plywood pieces wouldn't go all the way to the floor.

When I needed coal I merely took a heavy duty plastic shovel with a square blade (slipped under the coal easy) and took some coal from the bin and put it into a special coal pail (hopper).  Then over to the stove and dumped it into the top and had another several hours of comfy heat.  Wish I had taken a pic of it  .  I still have the shovel and the pail. 

Oh yeah, back then we could buy bulk by weight

Al

[Ed/KB1HYS]

It was a good heating system. Just a little less convenient than oil, unless you had a top of the line furnace with an auto-stoker system, which most average joes couldn't afford. I think it was the mess with the coal dust and the ashes, and the required work that made most folks go over to oil heat.

Anyone remember Blue Coal ads?

[k4kyv]

I remember fireplaces with coal  grates when I was a kid. I enjoyed watching and listening to the psychedelic blue flames that would blow out of a lump of coal as it heated up and outgassed.

And the iron poker used to punch the fire and let the ashes fall to the bottom. My first pyrotechnic experience, at pre-school age, was to stick the poker into the fire and pull it out once it got red-hot.  I never managed to set anything on fire or burn the house down.

I can still close my eyes, reminisce, and feel my face and shins scorch while my back side is freezing.

[K1JJ]

I think I found the goods for the job - these are 120VAC 2.5A  blower motor contollers for only $7 each on eBay. I ordered four and will test them out and report back.   The feedback on them is good in the ebay files.

T

http://cgi.ebay.com/Solid-State-AC-speed-Control-for-Blower-motors_W0QQitemZ140451274231QQcategoryZ71393QQcmdZViewItemQQ_trksidZp4340.m444QQ_trkparmsZalgo%3DCRX%26its%3DC%252BS%26itu%3DSI%252BUA%252BLM%252BLA%26otn%3D5%26ps%3D63%26clkid%3D5168298676862381365

[W1RKW]

vary the speed by changing the frequency.  Maybe a homebrewed amp with a fist full of FETS and a signal generator might do the trick???

[WA1GFZ]

Bob,
Fans will suck a lot of current at a lower frequency (Xl)

[K1JJ]

http://cgi.ebay.com/Solid-State-AC-speed-Control-for-Blower-motors_W0QQitemZ140451274231QQcategoryZ71393QQcmdZViewItemQQ_trksidZp4340.m444QQ_trkparmsZalgo%3DCRX%26its%3DC%252BS%26itu%3DSI%252BUA%252BLM%252BLA%26otn%3D5%26ps%3D63%26clkid%3D5168298676862381365

These work very well on both a blower or muffin fan.  They appear to perform much like a Variac.  One blower could be turned down very slow while the other had a minimum threshold and then slowed to a crawl.

All in all, for <$ 7 each, highly recommended as an alternative to a Variac. (Limited to 2.5A, 120AC)  I have them installed on all three related fan/blowers for the coal stove.


BTW, Jay, the stove black polish worked out FB. Looks like a new stove, tnx.

T

[WA1GFZ]

Fire the stove up before it gets cold. This way you can open the windows to let the smell out. Once the paint has been heated once you will be fine.