240 Blower Motor on 110

[coleman10]

I've read through a few similar posts on this, but they don't seem to fit the bill and I'm having a pre-senior moment with this for some reason.

I just replaced my AC and grabbed the blower motor out of the air handler so I can use it in the garage. It's 240, does not have a capacitor (no brown wires), and the speeds are selected by dip switches, not by hooking up one of three wires to hot. There is one pigtail connector for the power, red and black, and a ground coming directly off the motor. I included the schematics below just in case.

So my question with this is, if I want to hook it up to 110, do I connect one of the 240 legs to hot or both legs to hot? I'd hook up the ground, of course, but since there isn't a common, I guess I'd just cap or tape that off on the wire I use. ? The white wires are shown in the schematic as low voltage, not line voltage, so I guess the power to those have already already been stepped down.

Thanks, guys.

 

[Norcal]

The blower motor is most likely a 208-230V motor and the only way it will run on 120 volts is with a transformer to boost the voltage to 240V from 120V, not worth the effort and money.

 

[coleman10]

The blower motor is most likely a 208-230V motor and the only way it will run on 120 volts is with a transformer to boost the voltage to 240V from 120V, not worth the effort and money.

Well, that’s not what I’ve seen on numerous posts at other sites and on YouTube. It should run fine on 110.

 

[TuxThePenguin]

Can you post more info about the motor itself? Does it have a tag you can show a picture of? There are several different types of motors you can buy (split phase induction motors, universal motors, shaded pole induction motors, tons more and tons of little variations). Depending on the type of motor it is, running a lower voltage might not give it enough power to start, or it might start and just run slower, or it could try to draw additional current (which may cause it to burn up if the wire gauge it was built with cannot sustain that current). I'm not that familiar with HVAC components and I'm not sure what kind of motor they generally use (and even if I knew what type of motor they "generally use," there are always exceptions)

A general answer to "can a 240v motor be used at 120v" is a definite "maybe"

 

[sberry]

Maybe you right and maybe he is wrong, its your blower, wire it up. Report back. Sounds like a hobby and non critical and the fault protection in a "110" circuit is likely adequate, might use 15 or gfci too give it a whirl.

 

[sberry]

Well, that’s not what I’ve seen on numerous posts at other sites and on YouTube. It should run fine on 110.

Are they guesses or facts and does any show this running after the fact? Without investigating or having my tech look I am not sure. Norcal and I are not close personal friends but he is a master. I would consider this if I was doing it.

 

[coleman10]

Are they guesses or facts and does any show this running after the fact? Without investigating or having my tech look I am not sure. Norcal and I are not close personal friends but he is a master. I would consider this if I was doing it.

Yes, a couple videos I pulled up last night were basically, “See? A 240 blower will run on 110” and had multiple comments from others that said they had done the same thing had theirs running for years, but they didn’t go into the actual wiring. I’m assuming it will run slower than normally at 110 and that’s okay. I don’t need it running at full blast.

No, this is not a critical component so I’ll give it a shot and see what comes of it. I figured since I had the blower available I could put it to use. Someone on another thread here about garage fans had suggested repurposing an AC blower so that’s where I got the idea.

 

[Dumber than lumber]

I remember years ago hearing that a 220v light bulb will last forever running continuously on 110v. Some old timers used to put the bulb inside an old refrigerator and remove the door switch. Then use that to store welding rods and keep them dry.
So i can see how the fan arrangement could work.

 

[Norcal]

If someone believes everything on YouTube, there is a bridge in Brooklyn for sale, and a certain tower in Paris being offered for scrap.


The motor will spin on 120V but it will stall easily, HVAC equipment is built to a price point so they are not going to spend extra for a dual voltage motor, same reason definite purpose contactors are used, they only need to last until the warranty expires.

 

[Norcal]

I remember years ago hearing that a 220v light bulb will last forever running continuously on 110v. Some old timers used to put the bulb inside an old refrigerator and remove the door switch. Then use that to store welding rods and keep them dry.
So i can see how the fan arrangement could work.

Ever used a 240V lamp on 120V? They are rather dim.

 

[coleman10]

If someone believes everything on YouTube, there is a bridge in Brooklyn for sale, and a certain tower in Paris being offered for scrap.


The motor will spin on 120V but it will stall easily, HVAC equipment is built to a price point so they are not going to spend extra for a dual voltage motor, same reason definite purpose contactors are used, they only need to last until the warranty expires.

Oh, I don’t believe everything I see on YouTube, just like I don’t believe believe everything I read on forums, but if I see something that piques my curiosity, sounds reasonable, and it’s not costing anything, there’s no reason not to give it a try.

 

[dave*99]

I think you have an ECM motor there. In normal use, 240V is connected to the motor (your R&B wires) and the other small white wires carry 24V programming voltages to an electronic control board in the motor housing. This programs the motor speed. And I don't think it will run at all without voltage applied to the 24V terminals.

As for trying to run THIS SPECIFIC 240V motor on 120V..... prolly not.

 

[coleman10]

I think you have an ECM motor there. In normal use, 240V is connected to the motor (your R&B wires) and the other small white wires carry 24V programming voltages to an electronic control board in the motor housing. This programs the motor speed. And I don't think it will run at all without voltage applied to the 24V terminals.



As for trying to run THIS SPECIFIC 240V motor on 120V..... prolly not.

Makes sense.

 

[Dumber than lumber]

Ever used a 240V lamp on 120V? They are rather dim.

Maybe that explains the genius of the welding rod storage trick. Bulb doesn’t burn out for years, so the welding rods stay dry.
Remember please, must of us here are learning and trying to help one another by exchanging information, etc.
Thanks for being part of the process!!

 

[sberry]

I wired 2 lamps in series for my rod box. Worked well and was reliable. But this is different type of load.

 

[wyliesdiesels]

Well, that’s not what I’ve seen on numerous posts at other sites and on YouTube. It should run fine on 110.

Yes, a couple videos I pulled up last night were basically, “See? A 240 blower will run on 110” and had multiple comments from others that said they had done the same thing had theirs running for years, but they didn’t go into the actual wiring. I’m assuming it will run slower than normally at 110 and that’s okay. I don’t need it running at full blast.

No, this is not a critical component so I’ll give it a shot and see what comes of it. I figured since I had the blower available I could put it to use. Someone on another thread here about garage fans had suggested repurposing an AC blower so that’s where I got the idea.

Are you comparing apples to apples? probably not.

What you have is an electronically controlled blower motor. Notice the 9-pin harness? That should've been the dead giveaway. this is connected to a control board that controls the motor speed. a regular non-ECM motor will have 3 leads- 2 hots and a ground, but NO control harness.

connecting 120v to it won't do diddly without also connecting the control board and the motor could overheat since the amp draw will double. The motor is a single volt motor.

either get a 120v/240v transformer and the correct control board or just scrap it and buy a multi-volt non-ECM motor.

I remember years ago hearing that a 220v light bulb will last forever running continuously on 110v. Some old timers used to put the bulb inside an old refrigerator and remove the door switch. Then use that to store welding rods and keep them dry.
So i can see how the fan arrangement could work.

apples to oranges. you cant compare a resistive load to an inductive load. not the same...

I think you have an ECM motor there. In normal use, 240V is connected to the motor (your R&B wires) and the other small white wires carry 24V programming voltages to an electronic control board in the motor housing. This programs the motor speed. And I don't think it will run at all without voltage applied to the 24V terminals.

As for trying to run THIS SPECIFIC 240V motor on 120V..... prolly not.

Bingo. beat me to it

 

[sberry]

If I needed one would be hard pressed not to buy something comes cord and plug. I understand salvage or using it as part of a machine but would toss it before investing in salvage.

 

[Bert_]

It's an ECM motor. It needs a circuit board and a bunch of BS to make it work. Not worth the time. I would swap in a PSC motor before I put any time into making the ECM motor work.

PSC is just a regular capacitor motor. Permanent split capacitor.

 

[coleman10]

Thanks for the explanations, folks. It’s all a learning experience. I’ll set it out for a scrapper to pick up and stick to a box fan for now. I have other projects to focus on right now.

 

[TractorJeff]

Maybe that explains the genius of the welding rod storage trick. Bulb doesn’t burn out for years, so the welding rods stay dry.
Remember please, must of us here are learning and trying to help one another by exchanging information, etc.
Thanks for being part of the process!!

When I was a kid, in the winter for our chickens water pan, we used a 100w 240v bulb on 120v partially submerged to keep the water from freezing. Worked great as long as the bulb was cold before you submerged it!
I know its not related to the OP Thread but just throwing it out there as light bulbs were mentioned.

 

[nadogail]

If I wanted a 120 volt blower for a shop ventilator, I would visit a local HVAC shop with something of value and make an informal trade.

A couple of six packs of adult beverages on a hot Friday Afternoon or a box of doughnuts and a container of coffee early in the morning.

 

[American Locomotive]

There is so much misinformation in this thread.

First, you have an ECM fan motor. The vast majority of ECM fan motors are dual voltage and a simple jumper switches betwwen 120v and 240v mode. More pictures would help here.

Second, most residential ECM motors are super simple to control. Just apply 24VAC between Pins 1 and 4 (use something lile a dorbell transformer) and it will light off.

 

[coleman10]

There is so much misinformation in this thread.

First, you have an ECM fan motor. The vast majority of ECM fan motors are dual voltage and a simple jumper switches betwwen 120v and 240v mode. More pictures would help here.

Second, most residential ECM motors are super simple to control. Just apply 24VAC between Pins 1 and 4 (use something lile a dorbell transformer) and it will light off.

You know, I had thought about that, but in the end, it was bulky, heavy, and would be difficult to move around the garage. I set it out for a scrapper to pick up. A box fan is probably better for the space I have.

 

[GonzoAcres]

Ever used a 240V lamp on 120V? They are rather dim.

Thats why they last indefinitely, because they are not operating at they maximum tolerance for their entire life time, and eliminating the additional stresses caused by the element expanding and contracting during on/off cycles further provides longevity to the filament..https://youtu.be/j5v8D-alAKE

 

[alfredeneuman]

You do realize this is a "zombie" thread almost 2 years old, don't you?