DIY Chatroom Home Improvement Forum

DIY Chatroom Home Improvement Forum (http://www.diychatroom.com/)
-   HVAC (http://www.diychatroom.com/f17/)
-   -   Condenser fan noise and then blade breaks. (http://www.diychatroom.com/f17/condenser-fan-noise-then-blade-breaks-187755/)

whotheguy 09-28-2013 02:52 PM

Condenser fan noise and then blade breaks.
 
3 Attachment(s)
Hi all. I've got a heck of a head scratcher and was hoping I could bend the forums ear for a moment. My neighbor, a lovely retired senior citizen had me take a look at her outside unit because it was making noise. I've had a hand in a few repairs so I have some knowledge. She had her condenser fan motor and capacitor replaced about 3 months ago.

Tech said to also replace the fan blade, but didn't have one. I contacted the manufacturer and got one for her a few days later and installed it. Her old one would make a growl/vibration sound for about 1/2 a second at start up and then noise would be gone. Tech said the fan was out of balance, hence the replacement. After replacing with one I got from Goodman, #B1086775S-(22", 27 deg pitch), it sounded fine at start up, no noise. Couple of days later it started developing a noise while running, that lasted a couple days and then went away.Funny thing with that noise was when it was running you could give it a little bump with your fist on the top panel above the motor mounting area and the noise would go away, but only for a few seconds. Anyhow, weeks go by and the original growl/vibration sound came back. Well last night it was making a heck of a racket, I could hear it in my house, noise lasted about 1 minute and then a final "crash" sound. I went next door and pulled the circuit breaker, took a peek inside the housing, fan is missing a blade. Further looking and it's lying in the bottom of the unit. It's a miracle in my opinion it did not puncture the coil.

She had her old fan blade so I pulled the broken fan, fired up the motor for a couple of seconds to eliminate it as the problem, then installed the old, original fan. Turned it on, same noise as when it was originally on, that growl/vibration sound. Again, only lasts about 1/2 a second and only at start up. I got to thinking maybe they put in a 1075 RPM motor when the original was an 825 RPM. The motor is an Emerson K55HXCLF-586--1075 RPM, speeds 2, volts 208-230. I did some looking online for what her original motor would be and I found it to be also a 1075 RPM but 1 speed. Her unit is a Goodman CLJ48-1C. I'm afraid that this fan is going to to do the same thing. Anybody have this type of experience?

I'm wondering if I need to look at the height of the blade in relation to the motor when installed on the motor shaft. I'm concerned I'm having a venturi problem with the fan deck. I've tried finding the spec's, but I can't find it. Tech that replaced the motor had installed the fan on the shaft with the hub about 1" from the motor. I replaced the fans in the same location. I wonder if the techs location was wrong and that's what's causing all the noise.

I've attached some pics of the broken fan.
Thanks for any help.

gregzoll 09-28-2013 03:07 PM

I would pull the motor, and take it to a local motor shop to have them look at it. They can tell if the bearings are shot, and that is causing the problem, or something else.

As long as you get the fan on correct, the motor is true top to bottom, there should not be a problem with it tearing the fan blades up, unless something is catching inside, or the motor is getting ready to go out.

beenthere 09-28-2013 04:17 PM

May not have been riveted correctly from factory.

yuri 09-28-2013 05:32 PM

the position of the blade is important in how much air it scoops and how. I try get them mounted so the middle of the blades is inline with the bend in the cowl. hard to describe, the cowl may have a round lip on the inside and that may be the middle position. you don`t want it so low it is under the cowl and not real close to the top either. if you can't figure that out try get the blades about 1" down from the top. better to be close to the top then submerged under the cowl lip.

the other big problem may be that the condenser coil is very dirty and not enough air is going thru or the air pattern is bad. remove the entire fan and backwash/ shoot water thru it as that is the only proper way to clean those coils. then spray water sideways thru the cover to wash/ flush out the crap.

whotheguy 09-28-2013 05:42 PM

Quote:

Originally Posted by yuri (Post 1247402)
the position of the blade is important in how much air it scoops and how. I try get them mounted so the middle of the blades is inline with the bend in the cowl. hard to describe, the cowl may have a round lip on the inside and that may be the middle position. you don`t want it so low it is under the cowl and not real close to the top either. if you can't figure that out try get the blades about 1" down from the top. better to be close to the top then submerged under the cowl lip.

the other big problem may be that the condenser coil is very dirty and not enough air is going thru or the air pattern is bad. remove the entire fan and backwash/ shoot water thru it as that is the only proper way to clean those coils. then spray water sideways thru the cover to wash/ flush out the crap.


I think you're on the right track Yuri. Although I don't understand about the cowl. Are you referring to slotted, thin metal that wraps the coil? What I did do just now was, went out, pulled the cover with the motor'/fan attached. Loosened the fan and slid it up and down the shaft in about 1/8" increments. Each time I moved it to a new location I tightened it down, put the lid back on and turned it on. Every location, but one, would make the same loud noise. I did find one spot on the shaft that reduces the noise by about 90%. It happens to be roughly 1.4 inches below the motor. I'm going to leave it there and see what happens over time.

I did mean to backwash the coil while I had the cover off, I forgot. I'll be doing that now.

Thanks for the help Yuri.

If anybody else has something that I might try, I'm all ears, but I think I'm
on the right track.

Yuri, I'll try taking some pics of the inside and post them.

yuri 09-28-2013 07:10 PM

the cowl is the inside part that diverts air thru the top in my terminology.

yeah take pics of the inside. I do mostly Lennox and they have a rounded inner edge that I use and know well.

whotheguy 09-28-2013 07:47 PM

2 Attachment(s)
Here is some pics of the inside and where I last positioned the blade. A little blurry, but you should be able to see how the inside is laid out. Also back-washed the coil, not much in there.

yuri 09-28-2013 08:02 PM

Yeah Goodman does not have an internal cowl. Just have to play with it until it works OK. on lots of those I have added some foam insulation tape on the top piece the motor attaches to and where it sits on top of the coil to reduce vibration. You may see a small piece there already.

HVAC1000 09-29-2013 12:43 AM

Quote:

Originally Posted by yuri (Post 1247453)
Yeah Goodman does not have an internal cowl. Just have to play with it until it works OK. on lots of those I have added some foam insulation tape on the top piece the motor attaches to and where it sits on top of the coil to reduce vibration. You may see a small piece there already.

the nicer goodmans have a cowl those old and cheaper builders grade ones dont have it

cruies 09-30-2013 05:11 AM

Lock down screw is out...WD40 spray the hub and exposed Shaft. Takes a channel lock and grab the shaft between the "motor and the Blade" turn the hubfan blade area with your hand turn back and forth it Will break loose.... Sand the exposed shaft above the blade so it can slide Off. Be careful with the blades of that fan if they get bent you'll have to get A new one.
Thanks ALL

gregzoll 09-30-2013 05:14 AM

Quote:

Originally Posted by cruies (Post 1247933)
Lock down screw is out...WD40 spray the hub and exposed Shaft. Takes a channel lock and grab the shaft between the "motor and the Blade" turn the hubfan blade area with your hand turn back and forth it Will break loose.... Sand the exposed shaft above the blade so it can slide Off. Be careful with the blades of that fan if they get bent you'll have to get A new one.
Thanks ALL

Say what? Did you bother to read the first post of the thread, to see what is going on?

Doc Holliday 09-30-2013 08:59 PM

825 original rpm is supposed to be replaced with an, if generic, 830 rpm motor. while there are allowances in changing horse power, it should be the same hp as well. each motor coincides with an exact matching capacitior as well.

other than that, the lid the fan mounts to may be out of whack (bent) and/or your condenser coil needs cleaning to assist in proper air flow. Minor as far as vibration, major as far as air flow/condensing/efficiency, the cleaning.


All times are GMT -5. The time now is 05:37 PM.