Speed control

[WESTVIRGINIAMAPLER]

My speed control for my forced air blower has went bad on my evaporator. I am curious if this will work. I can't see why it wouldn't?? I already have my blower wired up with a commerical grade 8 or 10 gauge extension cord with a 3 prong wall plug in on the end. This way I can plug and unplug it whenever not in use. Couldn't I just mount this on the wall and plug the blower into this?? This is nice as it even has a built in on/off switch. Here's the link to item at harbor freight:

http://www.harborfreight.com/cpi/ctaf/Displayitem.taf?itemnumber=43060

[mapleman3]

Hey Brandon, got your call today, was in a boiler room and couldn't talk, the switch I don't think will work, your blower is not a brush type motor, sure it will handle 15amps but I don't know how it will work on the blower you have... may need to check with Graingers.com Maybe Rick can chime in on this.. he's a real good motor man!!

[WESTVIRGINIAMAPLER]

The speed control I had on my blower was 10 amps if that helps any. I seriously doubt that most applications this is used for uses 15 amps. I think it is just a 15 amp circuit in case you are running anything that large. I wired my build with all 20 amp circuits. :D

[digman_41]

Brandon, my forced draft is homemade. The wiring from my fan is hooked to a reostat that is used for a celing fan. I just wired the reostat in a switch box on the side of my arch, and from the box to an outlet with a 3 prong cord. The switch cost about $10.00 it has worked out great, I assume the blower on your arch draws fairly low amperage so a celing variable speed switch should be fine. It was fairly simple to hook-up.

Good Luck, Mark

[WESTVIRGINIAMAPLER]

Mark,

That is exactly how mine is wired up also and the blower came with a 10 amp control switch. I went to an electrical supply placed and they supposedly ordered me on for $ 17 and when it showed up, it was a 3 amp switch. I don't know if the blower motor is bigger than 3 amps or not. I don't have it here and it is about 30 minutes away at the sugarhouse. Wish I knew for sure as the switch I got would work if so, but I like the looks of the one at Harbor Freight. I don't know what the normal amps is for a blower like that. I have a new harbor freight catalog with the speed control on the back page for 1/2 the price it is on the website.

This morning when I went to the website, they were $ 9.99 and now they are $ 24.99. 8O

[NH Maplemaker]

Brandon, I just got a new Harbor freight catalog yesterday and the 15 amp router speed controler on the back page is selling for $12.49 was 24.99. The item # is 43060-2RMB. Then on page 34 they have the same picture differant item # 43060-1RMA with out any details for $19.99 and it looks identical. I think the catalog # is 755-D/winter2005, and again I just got this catalog!

[syrupmaker]

Brandon.... Motors can be fussy with varying the voltage to them. Look and see if the nameplate says if it is a split phase or a shaded pole motor. The best to have for speed control motors will have a tin or silver looking can(run capacitor) straped to the blower housing or banjoed to the motor itself. Let me now and I'll see what we can do for you.

I'll send you a PM for what else to look for.

Rick

[FMWARREN]

Brandon if your rheostat was a factory leader , go to Home Depot and buy a 20amp light switch dimmer,it will have a push on or off and will do the job.FM

[sweetwoodmaple]

Yup, did the Home Depot number on mine and it worked great. Of Course, it's back to square one as I have a new evaporator and will have to fabricate something else. Was thinking of using my spare squirrel cage from my house furnace... That should give me lots of air (1500 CFM +)
:twisted:

8O :wink: Harbor Freight cracks me up. If you find something cheap, MAKE SURE to write the item # down as it usually locks in the price. They are notorious for having the same item listed several time in the catalog with different prices.

Even if you go to the web site or call and see a higher price, give them the item number and it should be ok.

Brian

[Sugarmaker]

Make sure you ask if the item is on sale? It saved me $20.00 on the winches I just bought at Harbor Freight.

[WESTVIRGINIAMAPLER]

Guys,

Thanks for all the help. The electrical supply places around didn't even carry a fan speed control switch and wanted a small fortune for a 3 or 5 amp. I went to Lowes and thought I would check there and they had 5 amp fully variable switches in stock for $ 9.99. They only had two, so I swiped both of them as my blower is a touch under 2 amps! :D

[maple flats]

If you can't find a speed control you could do like many outdoor furnaces do. Just put a damper on the inlet to the blower and vary the air that way, need more pivot it open more, need less, restrict it more. You will find this works fairly well. You can even put marks for reference to know where to set it. The pivot point will need to be fairly tight OR you can have a pin to set and physically hold it in position for several settings. You will find that a little change in inlet air makes a big change in airflow out so the adjustments tend to be rather small, especially if the blower is a little bigger than needed. A blower speed control is easier, but this does work.

[Amber Gold]

I need a variable speed switch for my blower and found these two on Graingers website.

http://www.grainger.com/Grainger/items/6E897

http://www.grainger.com/Grainger/items/1DGV1

Will either of these work and would one work better than the other?

Thanks

[danno]

Josh - I've run an $8 dimmer switch from Loews on my 550 cfm blower for the past two years and it's worked fine. I'm hookin' up the 1100 cfm furnace blower to give me air over and under the fire this year - might be pushin that on the dimmer, but I'll probably give it a shot. This one was free and old furnace blowers are a dime a dozen.

[johnallin]

I'm still pretty new at this and have a question for you guys. I know many use blowers and there must be a reason, but I can't figure out how it saves any wood.

If I put a blower on my half pint, won't I just be burning more wood and sending more cold air into the fire box? I can leave the draft wide open and the only real change I see is that the boil looks like it goes down a notch, if dark enough I see a plume at the stack top, and I have to feed wood more often.

A steam engine buddy told me that I should try to keep my wood loading down to 3 seconds with the door open to help prevent all the cold air from coming into the fire box.

Thanks..

[Haynes Forest Products]

Go with the 1dgv1 its ment for motor speed control. Dimmers for incondesent lighting dont last with the heavey motor load. Remember whats cheap in the beginning is the most expensive in the end.

[parsissn]

johnallin,

What happens is you provide more air to the fire, in turn this causes more complete combustion of the wood - specifically the flue gases the burning wood gives off. In a normally drafted fire, much of the gas going up the stack has not actually combusted and is therefore wasted potential heat. With forced draft (blower) you are providing the missing part of the equation (additional combustion air) that allows those gases to more fully burn thus putting out more heat per unit of wood fuel. It's not that your fire is hotter, but instead maximizing the heat output of your wood fuel source.

As for short firing time, that mostly applies to a boiler, not an arch. We own several steam engines. In a steam engine, the cold air coming in above the fire from the fire door can cause contraction of the firebox walls and the fire tubes in the boiler. Over time this can cause stress on the metal plates and loosening of the boiler joints if such a cooling cycle is repeated often. In a single walled firing container such as an arch this really isn't much of an issue. You still probably don't want to just leave your fire door standing open but the time the door is open is not nearly as sensitive as a steam engine firebox.

On a related note, who is your steam buddy? I know many (but not all) of the engineers in Ohio.

Mark

[3% Solution]

johnallin,
Well, the two examples I can think of would be a blast furnace (kinda what you have there, only smaller) and a blacksmith using a bellows in his shop.
Look into the firebox of that steam engine someday, notice how bright the flame is ......... white or almost white, now that's hot.

So with that said, you are basically super oxygenating the fire box, forcing that oxygen into the firebox, and the fire gets hotter (more BTU's) and the wood burns more completely.

You can force more air in with the blower than the draft door will allow to come by natural convective currents (hot air rises).

About burning more wood; a pound of wood will release x # of BTU's no matter the species of tree. You need a total of xxxxx BTU's to evaporate 10 gallons of sap. You can evaporate that in (just using numbers here) 10 minutes with a blower or you can evaporate that in an hour without a blower.
So my point is, your saving time and getting the most out of your wood.

Here's another example; turbo charger on an engine, same thing. Gives you more horsepower.

Hope this helps!!!

Dave

[3% Solution]

parsissn,
Thanks for the help there.
When your burning those gasses, we in the fire service call that a "flashover"
1800 degrees and most of the flame is black so you can't see it.
Sometime if you look it the firbox or under the flues mostly, you see flames floating around that kinda resemble a Jellyfish, that's the flashover!

Thanks

Dave

[johnallin]

Mark,
Thanks for the reply, it is making more sense now. I could not figure out how it could work in light of the cold air thing I was hung up on and trying to keep the box as hot as possible.

The steam buddy is Chan Bleil from Mentor, he and another friend Tom Meakin used to own "Moon Fleet" a steam boat. If you're into steam in Ohio I'm guessing you know them, they've both been out here several times.

John

[johnallin]

Dave,
Thanks to you also, sounds like wood is wood, but I know the locust burns like hell fire.

I also use it in the shop wood stove, maybe some just burn hotter with less help.

[WESTVIRGINIAMAPLER]

Gotta love the locust, that is mainly what I burn and it is all nice and dry and most of it has been seasoned for several years.

Lowes has a fan speed control for $ 9.99 and it is up to 5 amps. I am not an electrician, but I think you need a fan speed control and not a dimmer switch. I can't find the speed control on Lowes online, but I have one at my sugarhouse that is currently on it's 3rd season and I have two more spare ones and will try to get the exact info if I can remember. I was in there about a month ago and they still carry them.