Carrier furnace ECM blower motor problems
#1
08-06-17, 08:17 AM
Carrier furnace ECM blower motor problems
blower doesn't run and I took out blower to check out. After I disconnect blower motor control module, I tested resistance as manual said:
1) resistance between any motor leads
- I got 3 leads here, I tested between 1-2, 1-3 and 2-3, Got 10.6 reading, good!
2) resistance between any motor leads to unpainted motor end plate
- where is unpainted motor end plate?
I randomly pick up some place on motor and got 0 reading to any 3 motor leads. It is not good, it sounds i have to replace motor on this carrier 58mvp080 , not cheap one.
Please help on how to do step 2 correctly.
1) resistance between any motor leads
- I got 3 leads here, I tested between 1-2, 1-3 and 2-3, Got 10.6 reading, good!
2) resistance between any motor leads to unpainted motor end plate
- where is unpainted motor end plate?
I randomly pick up some place on motor and got 0 reading to any 3 motor leads. It is not good, it sounds i have to replace motor on this carrier 58mvp080 , not cheap one.
Please help on how to do step 2 correctly.
#3
08-06-17, 12:25 PM
Group Moderator
There should be no continuity between any motor wire and ground. Ground is any metal part of the motor or the frame.That is what you have found which is correct.
Your motor appears to be electrically ok.
What is the problem ?
Your motor appears to be electrically ok.
What is the problem ?
#4
08-06-17, 12:59 PM
Forum Topic Moderator
Some meters may show OL and some may show 1 and some may show 0 when you have infinite resistance to ground.
You want the meter to give the same reading from each leg to the unpainted body of the motor that you get whet the leads are not touching anything. I believe that the Gentech manual state anything over 75000K Ohms is okay ( but I would want to see Infinite)
The module is the most common failure. The motor is often okay.
You want the meter to give the same reading from each leg to the unpainted body of the motor that you get whet the leads are not touching anything. I believe that the Gentech manual state anything over 75000K Ohms is okay ( but I would want to see Infinite)
The module is the most common failure. The motor is often okay.
#5
08-06-17, 02:48 PM
Thanks skaggsje, PJmax and Houston204
I think motor itself is OK after I saw picture in this blog "ECM Motor Troubleshooting — Part 2".
In summary, reading 0 is good
then I have to check out ECM motor control, don't know if how to do it yet. My problem is furnace blower didn't run from last week after a thunderstorm. 
I think motor itself is OK after I saw picture in this blog "ECM Motor Troubleshooting — Part 2".
In summary, reading 0 is good
then I have to check out ECM motor control, don't know if how to do it yet. My problem is furnace blower didn't run from last week after a thunderstorm. 
#6
08-06-17, 04:56 PM
Forum Topic Moderator
You can sometimes see obvious damage on the motor module after a storm.
If the motor is the ECM 2.3 with a 16 in connector, you can give the stat a cooling demand and measure between pins 1 and 6 for 12 (or 10) volts DC on the 16 pin connector to the motor.
If the motor is the ECM 2.3 with a 16 in connector, you can give the stat a cooling demand and measure between pins 1 and 6 for 12 (or 10) volts DC on the 16 pin connector to the motor.
#7
08-06-17, 06:50 PM
Thx Houston204,
I checked out ECM document and it seems this motor module is version 2.5.
I would read through this 58 paes ECM document to see if I can get more clues on motor module.
I checked out ECM document and it seems this motor module is version 2.5.
I would read through this 58 paes ECM document to see if I can get more clues on motor module.
#8
08-06-17, 09:59 PM
Group Moderator
I didn't realize that was an ECM motor. I didn't see anything other than the three pin connector on the back.
I'm guessing the back was removed before that picture was taken.
I'm guessing the back was removed before that picture was taken.
#11
08-07-17, 09:12 AM
Carrier furnace blower doesn't run
Last week, we got thunderstorm in the late afternoon. At night, I noticed no cold air came out. I found
1) COOL was ON, FAN was AUTO, no cold air
2) COOL was OFF, FAN was ON, no air
It seems blower issue. I was able to took out blower and I did 2 tests so far
1) tested resistance on motor, good
- see thread Carrier furnace blower motor resistance test
2) checked out input power of motor module
- it sounds weird, pin 5-4 120 VAC, pin 4-3 0 VAC, but pin 5-3 is about 65 VAC, sounds bad, what is the problem?
BTW my furnace is Carrier 58mvp80 f 15114, built in year 2001. ECM motor 2.5
1) COOL was ON, FAN was AUTO, no cold air
2) COOL was OFF, FAN was ON, no air
It seems blower issue. I was able to took out blower and I did 2 tests so far
1) tested resistance on motor, good
- see thread Carrier furnace blower motor resistance test
2) checked out input power of motor module
- it sounds weird, pin 5-4 120 VAC, pin 4-3 0 VAC, but pin 5-3 is about 65 VAC, sounds bad, what is the problem?
BTW my furnace is Carrier 58mvp80 f 15114, built in year 2001. ECM motor 2.5
#12
08-07-17, 09:56 AM
Group Moderator
#13
08-07-17, 02:09 PM
I assume input power to ECM motor module is good after I found "ECM textbook", it just mentioned pin 5-4 should be 120 VAC if jumper in pin 1 and pin2 or 240 VAC.
ECM motor module might be the problem and it would cost $400 in Canada. I also found lot of guys talked about SG 379 thermistor, I would check it out to see if it burnt up.
ECM motor module might be the problem and it would cost $400 in Canada. I also found lot of guys talked about SG 379 thermistor, I would check it out to see if it burnt up.
#15
08-07-17, 08:21 PM
Group Moderator
I have them that I purchased thru an online parts distributor. Many don't ship to Canada.
Here's one you should be able to get with no problem. Amazon ships over the border.
AMETHERM-SL22-1R020-THERMISTOR-piece/dp/B00FQURZSE
Ohm-Amp-Thermistor-SL22-1R020/dp/B018COFZR8
Here's some good reading.... http://www.doityourself.com/forum/ai...ble-motor.html
Here's one you should be able to get with no problem. Amazon ships over the border.
AMETHERM-SL22-1R020-THERMISTOR-piece/dp/B00FQURZSE
Ohm-Amp-Thermistor-SL22-1R020/dp/B018COFZR8
Here's some good reading.... http://www.doityourself.com/forum/ai...ble-motor.html
Last edited by PJmax; 08-07-17 at 09:10 PM. Reason: added thread link
#16
08-08-17, 08:19 AM
Thx PJmax,
I found that part at SL22 1R020 AMETHERM, Thermistor, ICL NTC, 1 ohm, -20% to +20%, Radial Leaded, SL22 Series, Newark element14 Canada Ordered it and waiting it come.
it is good thread http://www.doityourself.com/forum/ai...ble-motor.html !
I found that part at SL22 1R020 AMETHERM, Thermistor, ICL NTC, 1 ohm, -20% to +20%, Radial Leaded, SL22 Series, Newark element14 Canada Ordered it and waiting it come.
it is good thread http://www.doityourself.com/forum/ai...ble-motor.html !
#17
08-13-17, 07:51 PM
I unsoldered old g381 and soldered new purchasedc piece, well, I noticed I need more practice on soldering skill. Then i set blower back into furnace, it started blowing again!!! Cold air come back. My efforts paid off.
#18
08-17-17, 12:43 PM
bigpang where did you find that ecm document? I have GE ECM 2.3 not working. I have thread on it-Carrier furnace blower not working
So houston204 can I start testing by removing 16 pin plug from main control board (not motor module) and testing for voltage between pins 1 and 6 on the board when I turn fan to "on" on thermostat as you mentioned above. My thread seems to have died never got testing info and removing it to look for burnt up circuit is not feasible (see my thread )
So houston204 can I start testing by removing 16 pin plug from main control board (not motor module) and testing for voltage between pins 1 and 6 on the board when I turn fan to "on" on thermostat as you mentioned above. My thread seems to have died never got testing info and removing it to look for burnt up circuit is not feasible (see my thread )
#19
08-20-17, 08:12 PM
hammerash,
I got idea from this guy on how to unsolder and solder SG379.
https://www.youtube.com/watch?v=e8ye0rwv7tI
As for ECM document, check out this link.
http://www.prokupmedia.com/seminarfi...m_textbook.pdf
I got idea from this guy on how to unsolder and solder SG379.
https://www.youtube.com/watch?v=e8ye0rwv7tI
As for ECM document, check out this link.
http://www.prokupmedia.com/seminarfi...m_textbook.pdf
#20
08-20-17, 08:33 PM
Thanks. I ordered part on Amazon. About $8 extra For 1 day shipping. Got it today. Guy i know is electrical engineer so asked him and he has lot experience soldering on boards. He did it for me. Trying to get motivated to put back together but watching recording of IndyCar race from Pocono today.
