Everything Drolet Tundra - Heatmax...

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Anyone with an ICM controler on there sleeve bearing furnace... Looking for some input. How slow does your fan go when it's about to kick off?

I tried my ICM hooked upto blower speed 1 and also tried blower speed 2. Got similar results works great!! Just don't want to cook the motor. I like it hooked to blower 2 better for the simple fact its quieter at crusing temp with the odd surge to bring the plenum to the set temp. (Has little wider band for cfm output)

I have the ICM currently on max cutoff for sleeve and max hard start to ensure adequate lubrication.

The system seems to be working as expected. I'm not to consurned with the voltage... more so with the speed of the shaft to get proper oil. When the plenum temps drop to around 100f it is SLOW! But I'm not used the it.
 
Anyone with an ICM controler on there sleeve bearing furnace... Looking for some input. How slow does your fan go when it's about to kick off?
I have mine set in the middle range for a sleeve bearing motor on both settings on the ICM. I have no idea what speed the motor is going or the voltage of the motor at the settings I'm using. I don't have the nice Fluke meter like @JRHAWK9 has that reads RMS :p. I haven't messed much with it since I installed it. My furnace is set to speed 2 also.

Edit: I lied, I had it originally set in the middle and moved both to max. The motor was making some weird sounds when I had the cut out speed set in the middle. I forgot about that.....
 
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I have mine set in the middle range for a sleeve bearing motor on both settings on the ICM. I have no idea what speed the motor is going or the voltage of the motor at the settings I'm using. I don't have the nice Fluke meter like @JRHAWK9 has that reads RMS :p. I haven't messed much with it since I installed it. My furnace is set to speed 2 also.

Edit: I lied, I had it originally set in the middle and moved both to max. The motor was making sounds some weird sounds when I had the cut out speed set in the middle. I forgot about that.....

Ok good to know. I'll leave my sleeve setting on max for cutout. I know each motor has different characteristics... So long as the motor isnt making any noises it should be good? lol.
 
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Anyone with an ICM controler on there sleeve bearing furnace... Looking for some input. How slow does your fan go when it's about to kick off?

I tried my ICM hooked upto blower speed 1 and also tried blower speed 2. Got similar results works great!! Just don't want to cook the motor. I like it hooked to blower 2 better for the simple fact its quieter at crusing temp with the odd surge to bring the plenum to the set temp. (Has little wider band for cfm output)

I have the ICM currently on max cutoff for sleeve and max hard start to ensure adequate lubrication.

The system seems to be working as expected. I'm not to consurned with the voltage... more so with the speed of the shaft to get proper oil. When the plenum temps drop to around 100f it is SLOW! But I'm not used the it.
There is no lubrication to be concerned about on most sleeve bearing motors used on direct drive furnace blowers...the sleeve bearings are permanently lubricated..."oilite" bearings I think they are called.
If you see them mention lubrication in the ICM manual...you have to remember, these things are made for AC compressors...so they use the "hard start" for full voltage starting (since they are turning a compressor, that is a heavy load) and possibly for compressor lubrication too.
I have my hard start set to a minimum...a couple seconds...just enough to get the blower spooled up to full (ish) speed.

As far as the minimum speed...if it is barely moving air, and you are down the minimum setting for sleeve bearing motors, I see no sense in going any slower. Now if you have a ball bearing motor such as @JRHAWK9 has, then the sky is the limit with how slow you can go...and it sounds like he is getting great results with slowing his down a lot!
I also set the minimum speed somewhat by how much noise the motor made before it shuts off...some are noiser than others...and at different speeds...gotta experiment and see what works for ya. But in no case would I go below the factory minimum setting for a sleeve motor unless I had a ball bearing motor.

Just to be clear here...the main issue with controlling speed this way is heat buildup...but doing it on a centrifugal blower like this is an ideal situation to do it...way better than an AC compressor.
There is no high load at start up. (unlike an AC compressor)
The load lessens as the speed drops (unlike an AC compressor)
And the motor is in a cool environment (unlike an AC compressor)
Every blower I have tried this on remains no more than warm (not hot!) to the touch after long periods of low speed running...and I have not heard of one person losing a motor yet either.
 
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There is no lubrication to be concerned about on most sleeve bearing motors used on direct drive furnace blowers...the sleeve bearings are permanently lubricated..."oilite" bearings I think they are called.
If you see them mention lubrication in the ICM manual...you have to remember, these things are made for AC compressors...so they use the "hard start" for full voltage starting (since they are turning a compressor, that is a heavy load) and possibly for compressor lubrication too.
I have my hard start set to a minimum...a couple seconds...just enough to get the blower spooled up to full (ish) speed.

As far as the minimum speed...if it is barely moving air, and you are down the minimum setting for sleeve bearing motors, I see no sense in going any slower. Now if you have a ball bearing motor such as @JRHAWK9 has, then the sky is the limit with how slow you can go...and it sounds like he is getting great results with slowing his down a lot!
I also set the minimum speed somewhat by how much noise the motor made before it shuts off...some are noiser than others...and at different speeds...gotta experiment and see what works for ya. But in no case would I go below the factory minimum setting for a sleeve motor unless I had a ball bearing motor.

Just to be clear here...the main issue with controlling speed this way is heat buildup...but doing it on a centrifugal blower like this is an ideal situation to do it...way better than an AC compressor.
There is no high load at start up. (unlike an AC compressor)
The load lessens as the speed drops (unlike an AC compressor)
And the motor is in a cool environment (unlike an AC compressor)
Every blower I have tried this on remains no more than warm (not hot!) to the touch after long periods of low speed running...and I have not heard of one person losing a motor yet either.

I can't see the blower being much more useful going any slower than the sleeve cutout. It literally just blows enough air to feel at cutout at that setting... now a ball bearing lowest cutout I can only imagine not feeling air leaving the ducts... how is that useful?
 
now a ball bearing lowest cutout I can only imagine not feeling air leaving the ducts... how is that useful?
You have to remember that the ball bearing motor has lower rolling resistance, so it will turn faster at a lower voltage.
 
I also set the minimum speed somewhat by how much noise the motor made before it shuts off...some are noiser than others...and at different speeds...gotta experiment and see what works for ya. But in no case would I go below the factory minimum setting for a sleeve motor unless I had a ball bearing motor.
Like I said, I had my cut out speed set to in the middle and my blower motor was making some noises I don' think a motor should make. Even on max it makes some noises, but it will generally turn off shortly there after. I've kind of a alleviated the situation by turning up the cut out temperature on the snap disc to a little over 100.

If you see them mention lubrication in the ICM manual...you have to remember, these things are made for AC compressors...so they use the "hard start" for full voltage starting (since they are turning a compressor, that is a heavy load) and possibly for compressor lubrication too.
I have my hard start set to a minimum...a couple seconds...just enough to get the blower spooled up to full (ish) speed.

I'll probably turn my hard start setting back down to the middle. I'm with you @brenndatomu, no use of start something as hard as you can when you can start it nice and gentle ::-).
 
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I'll probably turn my hard start setting back down to the middle. I'm with you @brenndatomu, no use of start something as hard as you can when you can start it nice and gentle ::-).
Well, starting a motor on low voltage is not a great idea...but since there is almost no load (just getting the weight of the motor rotor and the blower wheel spinning) on a blower like these at low (no) speed, it will work...but I still like to give it a couple seconds to get up to speed, then the ICM lets the temp sensor take over and adjusts the speed accordingly.
 
I have no idea what speed the motor is going or the voltage of the motor at the settings I'm using. I don't have the nice Fluke meter like @JRHAWK9 has that reads RMS :p.

:) I actually just have a El cheapo Craftsman from about 15 years ago. It does read True RMS, which you do need. Otherwise your voltage reading will be inaccurate. You may have thought I had a Fluke because of the link I posted a couple times: https://www.fluke.com/en-us/learn/best-practices/measurement-basics/electricity/what-is-true-rms


As far as the minimum speed...if it is barely moving air, and you are down the minimum setting for sleeve bearing motors, I see no sense in going any slower. Now if you have a ball bearing motor such as @JRHAWK9 has, then the sky is the limit with how slow you can go...and it sounds like he is getting great results with slowing his down a lot!

I do have mine slowed down a lot and for some reason it heats the house better. It prefers lower volumes of higher temp supply air. Can't tell you why, but it does. The most voltage the motor sees, when the Kuuma is running full out, is ~70V RMS at max plenum temps. My low limit shuts it off when it's seeing around 45V RMS. So, it's pretty much running in the 40V - 75V RMS range at all times.
 
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:) I actually just have a cheapo El Craftsman from 15 years ago. It does read True RMS, which you do need. Otherwise your voltage reading will be inaccurate. You may have thought I had a Fluke because of the link I posted a couple times: https://www.fluke.com/en-us/learn/best-practices/measurement-basics/electricity/what-is-true-rms




I do have mine slowed down a lot and for some reason it heats the house better. It prefers lower volumes of higher temp supply air. Can't tell you why, but it does. The most voltage the motor sees, when the Kuuma is running full out, is ~70V RMS at max plenum temps. My low limit shuts it off when it's seeing around 45V RMS. So, it's pretty much running in the 40V - 75V RMS range at all times.

It could have alot to do where your ducts are located... maybe since your heat loss at your roof is significantly higher also with the tall ceiling it helps keep an even stream of heat lower to your floor level.
 
Like I said, I had my cut out speed set to in the middle and my blower motor was making some noises I don' think a motor should make. Even on max it makes some noises, but it will generally turn off shortly there after. I've kind of a alleviated the situation by turning up the cut out temperature on the snap disc to a little over 100.



I'll probably turn my hard start setting back down to the middle. I'm with you @brenndatomu, no use of start something as hard as you can when you can start it nice and gentle ::-).

I don't rely on just the ICM to shut off the blower motor- even adjusted to the fastest cut off speed it will run the motor down to what sounds like barely spinning. Instead I replaced the factory fan snap switch with an adjustable version that will cut power to the ICM. Between adjusting the snap switch and the 5k pot inline with the thermistor, I can get things to shut off at an appropriate rpm.

As far as the hard start, I set that to maximum because it's usually best to start loaded motors at full voltage, although this one is lightly loaded at start up so it may not matter too much if you soft start it.
 
It could have alot to do where your ducts are located... maybe since your heat loss at your roof is significantly higher also with the tall ceiling it helps keep an even stream of heat lower to your floor level.


They are pretty much all around the perimeter of the house.

One of my theories is what you have mentioned, maybe being more about the velocity coming out and the lower velocity doesn't send it straight up to the roof. Who knows. just glad I stumbled across it by experimenting. :)
 
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I don't rely on just the ICM to shut off the blower motor- even adjusted to the fastest cut off speed it will run the motor down to what sounds like barely spinning. Instead I replaced the factory fan snap switch with an adjustable version that will cut power to the ICM. Between adjusting the snap switch and the 5k pot inline with the thermistor, I can get things to shut off at an appropriate rpm.

I agree. This is how I have mine set up and allows me to easily experiment with different blower speeds.
 
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I also have a kick off for the icm about 95f. The factory tundra board controls my on/off cutoff. I tested the fan and it will still go much slower than the setting, but the board kicks it off before. I'm pretty lucky though... at the low sleeve bearing setting my blower is quite, to the point I don't know it's on not even a noticable hum!

The broad is still wired to cycle through the speeds if the plenum reaches over 135f (after resistor mod) which is highly doubtful.

What I have noticed if you disconnect the thermo probe on the icm while it's running the unit will kill the fan. Or if the icm fails it will kill the fan aswell. The way I have my icm set up, the tundra board will still take over in the event of failure or overheat. It can cycle through all the variable speeds if needed.
 
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Instead I replaced the factory fan snap switch with an adjustable version that will cut power to the ICM. Between adjusting the snap switch and the 5k pot inline with the thermistor, I can get things to shut off at an appropriate rpm.
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My Caddy is setup very similar to yours then minus the 5k pot. I'm not relying on the ICM to turn the fan off either. I'm still relying on the factory snap switch to do that. I've had a 5k pot sitting on my bench collecting dust for a couple years now. Maybe I should knock the dust off of it and finally install it.
 
My Caddy is setup very similar to yours then minus the 5k pot. I'm not relying on the ICM to turn the fan off either. I'm still relying on the factory snap switch to do that. I've had a 5k pot sitting on my bench collecting dust for a couple years now. Maybe I should knock the dust off of it and finally install it.

I'll have to double check... but I'm pretty sure I have the pot tuned for the icm to give full current at 115-120 f plennum. Maintaining very close to that set point.

What is your snap disk set at?
 
I'm not relying on the ICM to turn the fan off either. I'm still relying on the factory snap switch to do that.

Same here. I'm using the factory fan & limit furnace control to control the on/off of the blower circuit (low limit) as well as for my high limit. Works great.

It appears the motors which come with the Tundras are quiet when speed controlled. I think @DoubleB had mentioned in the past how his was nice and quiet back when he had it speed controlled. All the ones I've played with (5 total, including the stock one) all made some goofy resonate humming when getting down there in voltage.
 
I'll have to double check... but I'm pretty sure I have the pot tuned for the icm to give full current at 115-120 f plennum. Maintaining very close to that set point.

What is your snap disk set at?
My snap disk is set to turn on at 150 and to turn off at a little over 100.
 
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All the ones I've played with (5 total, including the stock one) all made some goofy resonate humming when getting down there in voltage.
My motor doesn't make a humming noise. It makes a noise almost like the power to it is being turned off and on really fast. It doesn't sound "healthy" by any stretch of the means. I'll try to get a video of it.
 
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My motor doesn't make a humming noise. It makes a noise almost like the power to it is being turned off and on really fast. It doesn't sound "healthy" by any stretch of the means. I'll try to get a video of it.

I'm thinking the cabinet it's sitting in is making it sound even worse.

Here at work for years we had an AC unit outside which would run in winter, all winter, I guess to keep our server room downstairs cool. I am pretty sure it had a head pressure control on it as the motor was always making a strange noise and the fan was always turning VERY slowly. One could actually watch it go around. Always wondered what the deal was with it.....until I speed controlled mine and remembered that setup. Things have changed since then, but that AC ran for lots of years with that motor spinning very slow. The noise I remember that motor making and what mine makes are pretty similar.
 
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Well, all good things must come to an end. My ICM speed controller gave up the ghost today. Got home from work today and made a fire and heard a click from the snap disc but the fan didn't turn on. Immediately pulled the power plug and plugged it back in and the fan still didn't run. Unplugged the furnace again and unscrewed and screwed the wire nut on the on the hot side of the ICM and motor and plugged the furnace back in and still no go. I then heard the cut out switch kick in and new it was time to unwire the ICM and wire the connections back directly into the furnace. Grabbed my book and wired everything back together and the fan kicked right on.

The controller I bought was brand new. I bought it and installed the ICM 326 in January of 2017. For now, I think I'll just stick with keeping my summer switch ( wired to speed 1 ) on all of the time and let that help circulate the warm air off of the furnace some.
 
Well, all good things must come to an end. My ICM speed controller gave up the ghost today. Got home from work today and made a fire and heard a click from the snap disc but the fan didn't turn on. Immediately pulled the power plug and plugged it back in and the fan still didn't run. Unplugged the furnace again and unscrewed and screwed the wire nut on the on the hot side of the ICM and motor and plugged the furnace back in and still no go. I then heard the cut out switch kick in and new it was time to unwire the ICM and wire the connections back directly into the furnace. Grabbed my book and wired everything back together and the fan kicked right on.

The controller I bought was brand new. I bought it and installed the ICM 326 in January of 2017. For now, I think I'll just stick with keeping my summer switch ( wired to speed 1 ) on all of the time and let that help circulate the warm air off of the furnace some.


well that sucks! I just looked back. I installed mine at the end of 2016. I hope yours was a fluke. I do have a spare one sitting on the shelf though if mine ever gives up.
 
My ICM speed controller gave up the ghost today.

Yea that stinks indeed. I agree I hope that's a fluke, I'm just paranoid enough of adding the ICM in series to the stock circuitry that's part of the reason I haven't been using it lately. Plus, I realized I actually like faintly hearing the blower cycle on/off from my room in the early morning...it tells me whether I need to get out of bed right away to warm up the house, or whether I still have good coals going. I lost that audible thermometer when I used the ICM. :rolleyes:
 
Yea that stinks indeed. I agree I hope that's a fluke, I'm just paranoid enough of adding the ICM in series to the stock circuitry that's part of the reason I haven't been using it lately. Plus, I realized I actually like faintly hearing the blower cycle on/off from my room in the early morning...it tells me whether I need to get out of bed right away to warm up the house, or whether I still have good coals going. I lost that audible thermometer when I used the ICM. :rolleyes:
Yep, I hope it is a fluke too. I'm actually bidding on another speed controller on eBay. I'm generally like @JRHAWK9 and have two of everything but for some reason I didn't have a backup speed controller. I listened to the furnace go off and on a couple times and thought it was really a step backwards in functionality. Of course my speed controller has to die right before the polar vortex is ready to hit.
 
Of course my speed controller has to die right before the polar vortex is ready to hit.
I would think you would be loading enough to keep the blower running during this extra cold weather though?
You still lose the extra efficiency that seems to come with the blower speed matching the heat output...but I think the blower cycling at the end is the real killer...