Results 1 to 9 of 9
Thread: replacement cond. fan motors
-
06-21-2008, 02:06 AM #1
replacement cond. fan motors
Why must everything be built like junk nowadays?
anyone else have problems with all of the new cond. fan motors in the larger older styled equipment?
I have some custies with older equiptment that keeps eating our replacement mortors. some of these units still have the 1970's original motor and blades in them kicking away yet the replacements are dying left and right.(about 1 or 2 a year) bad bearings.
1. i did pull the proper drain plugs
2. installed with proper voltage, and amped out after every install.
3. proper capacitors installed
4. have suggested to custie to buy phase protection multiple times to reduce problems.
5. replaced fan blades with motors.
6. proper rotation
I realize that this building has occasional brown outs and blackouts, but why dont the older motors have the same problems? drysucker (motor distributer) says that they have different tolerances on the bearings these days. but they don't carry motors with the old school bearings.
-
06-21-2008, 02:38 PM #2
Regular Guest
- Join Date
- Jun 2008
- Location
- Palmer Alaska
- Posts
- 8
old stuff is tuff
I've had the same problem with AAF, Trane, Lemonox (lennox) and others. The old motors are alot heavier and have longer cases. The replacement motors were lighter. After replacing several of these cheapies I looked for a heavier motor and found some that weighed twice as much and cost twice as much. Haven't had to change the heavy ones yet. had to modify a couple of brackets but the rpm, voltage, and hp were the correct ratings. I look for motors that are the exact voltage and rotation instead of the multi voltage-bidirectional units. They can be found. The multi tap motors are ok for smaller rooftops but the larger condensers need heavy stuff that can handle being switched on and off alot. Up here in AK with the low ambient, condenser fans get hammered. Good luck.
-
06-21-2008, 03:30 PM #3
I know the class of insulation and the service
factor that the motor has can make a big difference in the longevity of motors. I would also recomend using a ball bearing motor on any commercial unit if possible, the cost isn't much more when you look at it.Last edited by jayhawker; 06-21-2008 at 09:16 PM.
"Paddle faster, I hear banjo music"
-
06-21-2008, 03:43 PM #4
Regular Guest
- Join Date
- Jun 2008
- Posts
- 19
Have you replaced the blades? An unbalanced blade will cause bearings to wear.
-
06-21-2008, 03:57 PM #5
Have you tried one of the commercial motors? The regular motors at the supply house are made much weaker than a commercial one. All the motor specs will be the same, but the commercial motor is built to last, much heavier and cost 2 - 3 times the normal residential motor. I've tried replacing a commercial motor with a resi one (same specs, amps everything) it would last about 8 months.

The manufacturer doesn't really matter, they all have a better line of motors for a little extra.
Many of them are high static motors, which could "boil down"
to bearing failure. Overheating and loss of lubricant.

-
06-22-2008, 05:27 AM #6
thanx for the replies

i'll ask about commercial motors.
ace
-
06-25-2008, 12:36 AM #7
Regular Guest
- Join Date
- Nov 2007
- Location
- Charlotte,nc
- Posts
- 15
Went on several, that the motors had been changed several times, orignial fan blad on one,fairly new on the others, found out that the orignal motor was 1/4hp 850 rpm and that some hilljack was instaling 1/2hp 1175rpm, given bigger hp but not able to pull the deep pitched fan blades. I guess if he kept it up there would have been 1.5hp motors on the units
-
06-25-2008, 10:15 AM #8
If you carry a laptop with you, set up a login to Emerson. This is a useful site when you need to do a little research on the job. They have a wide selection of condenser fan motors.
www.emersonclimate.com/contractor"Excellence is the gradual result of always striving to do better"
-Pat Riley
-
06-25-2008, 11:26 AM #9
Professional Member
- Join Date
- Mar 2003
- Posts
- 7,249
planned obsolescence. We have become a throwaway society. They just don 't make things like they used to. Keep in mind that A lot of the motors in generic supply houses are not the right replacement for an oem motor no matter what the counter guy says. They are just not built the same. Especially in harsh applications like condensers.


Reply With Quote