Trane M/N TWE120A300DA
S/N 2443N0C5H MFG 02
Two of these air handlers mounted up about 20 feet in a open gym area.
We have to rent a high lift about every 3 months to service.
The blower belt usually is loose and squealing by the time we can get to it.
We have aligned the pulleys and replaced the worn motor sheaves.
I do not like the A50 belt! I wish to change the pulleys to a B size, hoping to get longer belt life.
Has anyone out their had this problem and a good solution?
Has anyone tried to put a spring loaded auto tension setup on these air handlers.? I saw a few auto belt tensioners in the Grainger catalog I thought about attempting to customize to fit.
Try switching to an AX50 and run the fan in the on position rather than auto. If this does not work than I would change sheaves and belt to a B
We gave the AX type belt a try same results.
I agree with continuous fan operation, but the coaches need the fans off during coaching sessions due to the noise. The fans are on Tracer Automation, but the coaches have over ride control of the fans. There is more to it, but in a nutshell, the fan needs auto cycling.
We are using the 2HP Standard motor using the Low Static fan drive. Motor sheave turned out 3 turns for a RPM of 627. Using low static to keep the noise down. Very echo sensitive area!
The motor adjustable sheave is 1VP44x7/8
The blower is a 1" bore, but we do not have the standard pulley size without getting the high lift back in there."PIA"
Does anyone have access to the blower pulley information.?
Last edited by dgruber; 09-11-2009 at 04:55 PM.
Might be a little costly, how about adding mini VFD'S for soft start?
Now that's a thought!
We already did that on the Indoor Soccer Field exhaust fans. Eight in total. Same situation, coaches had to control start stop!!
Since the soft start, which we custom built the control panels using Lesson Mini drives on 7.5 Hp motors, we have had no problems to date.
I will keep this in thought while we try to figure out the best option, but I like your idea.
After sleeping on it a thought came to mind concerning the soft start.
The condenser is a Trane tin can receip. Any thoughts on how it will handle the soft start. I expect the txv, if working properly, will respond accordingly.
I did add head pressure fan cycling last fall along and properly rewired the freeze stat. The system used to ice up prior to that.
Plenty of heat load when practice goes on no matter how cold outside normally, but we do have external gas heaters to keep the place warm during long breaks in the playing schedule.
I expect the compressors could handle soft start since we have condenser fan cycling and evaporator freeze stat protection, but thought I would bounce this off you guy's out there.
If the compressor had unloading capability I would not have much concern.
I guess as long as the ramp up time is programmed at least 30 hertz within 60 seconds then take it to say 47 to 52 hertz within another minute would be soft enough for the belts and quick enough for the refrigeration system to compensate. May keep it at 52 hertz to keep the air noise even lower if the pressures look good and not to much flood back for the compressors.
What say you?
You could install a delay on make timer to keep the compressors off until the fan comes up to speed.
What brand belts are you using? Browning belts are of a higher quality than the cheaper bando, goodyear, or dayton type. Try a browning ax50. Also if you are using an adjustable pulley I would switch it to a fixed pulley.
how "deep" is the belt riding into the pulley
Originally Posted by dgruber
i seen techs open them adjustable pulleys up too much, which will cause premature wear
depending on system activity, 3 months may be to much time between maintanances intervals
never needed a belt tensioner
slap bigger "B" series belts on it, that should last 3 months no prob.
with your safties and controls, a soft start "VFD" would be fine
Have you considered "OPTIBELT"? They might be pretty pricy, but I hear they out perform any other manufacturer of vee-belts.
Try "googling" "optibelt USA" to locate a distributer.
"Wheel" mechanics work on "Wheel" chillers
I agree with skoonen put a fixed pulley on that motor variable is good for dialing in a certain rpm/cfm but should be changed to fixed after that is determined, how do you like that run on sentence?
It takes three people to do anything around here. Two do the work, one explains to the crowd of people who showed up when they seen smoke and flames.