Regular Guest
Hi,
I had a 3.5 ton 14 SEER Amana RCE36C2C compressor installed as part of a new system a year ago. At the time, I thought it was kind of loud at startup. It makes a loud groaning noise until it gets up to speed, then runs quietly. I asked the contractor about this and he said it was normal.
Is it normal for an AC compressor to be noisy at startup? Is this hard on the motor or compressor? Is this something a hard-start capacitor could potentially help?
Professional Member
Your RCE36 is a nominal 3 ton, not 3.5T, a RCE42 would be a 3.5T
The RCE series uses scroll compressors & they do make a different sound on start up.
A hard start kit will reduce wear & tear on the compressor & is required if your unit is matched w/ a TXV coil. The RCE is ONLY rated w/ TXV coils.
Follow your contractors advice.
Regular Guest
My contractor gave me no advice as to the presence/absence of a hard start kit, or it's required installation in my model compressor when matched with the correct TXV coils you mention. Is there anything in particular different about 'TXV' evaporators? The evaporator installed is a Goodman CAPF3636B6AA.Originally Posted by coolguysfl
If the noise is normal, fine. But it certainly can't be helping wear, and if there is an option that would improve this otherwise-quiet compressors operation I would like to look into it.
If my compressor motor is not equipped with a start capacitor, can I improve start performance and decrease noise by adding one?
Professional Member
I'd better get my Goodman service truck ready.
<pic removed>
Jabs
Last edited by jrbenny; 08-26-2007 at 05:17 PM.
Membership Committee*
Twilli thinks all Amana's been groaning since they were bought by Goodman
No Heat No Cool You need Action Fast
Professional Member
I'd call the contractor back ----- let HIM validate the coil is an approved match.
BTW -- with the nomenclature, the F in the coil means Flow-rater, no TXV unless the contractor added it on.
Professional Member*
the noise you hear at start up may be a hermonic vibration from the compressor witch is common with a scroll compressor. This noise can be escalated it the refrigerant lines are strapped to the beams. If the smaller line is touching the wood or cement the noise can be transmitted to the house and can be in some cases quite loud.
ask your contractor to check and isulate the lines if possible
if this is what is causing the loud noise
Regular Guest
So the expansion valves are different? Obviously he believed the coils were correct, or he wouldn't have put them in.
Let me get this straight: you believe that the RCE36 should only be used with a TXV expansion valve, not the flow-rate valve in my evaporator? Is this stated somewhere in the Amana literature? It would be good to have some documentation when speaking with the contractor.
Professional Member
Why do you say you have a 3.5 ton unit the 36 in both numbers match and that is a 3 ton unit .I would check your contract and then talk to the contractor.
Regular Guest
The contractor stated he was going to install a 3.5 ton. Apparently he installed a 3 ton.
Global Moderator
Where is indoor coil?
Regular Guest
Furnace (Amana AMS95) is in the garage, draws through the side from the house, blows up through the evaporator into the ducts in the attic.
New Guest
First of all is the reason for the hard start kit is the TXV has a equilizing line that shuts the refrigerant flow off during off cycle. During start up the compressor has to overcome the inercia of the lack of equalization. there for the noise. Requiring the hard start Kit. The kit gives the conpressor the extra boost needed to get the compressor past the hump of locked rotor amps.
Checking the superheat of the unit would be wise. If liquid is feeding back to the system durring the run cycle. this would also be the symptom that you describe.
Also take note of your units run time. Does it cool? Does it short cycle?
Regular Guest
The compressor runs for 15 - 30 minutes when cooling is required. It cools OK, the ducts are 70's sheetmetal and could be larger. The TXV would be external to the evaporator in the liquid line, right? I don't think it has one. Should it? Would this improve performance?
Professional Member
I'm sorry, but that is just plain funny!I'd better get my Goodman service truck ready.
Jabs
New Guest
check the back of your thermostat make sure that the hole in the wall is sealed.
The orafice that is in the unit is okay but will allow refrigerant to migrate during off cycle.
It does not sound as if your unit is off long enough for the miration to take place durring off time. Could be a problem if you are slugging liquid back durring run time. Is the run of copper for your liquid line longer than 50'? Also how high is your evp coil (indoor coil) in relation to your condenser unit?
Regular Guest
The lines are about 30' long. The evaporator is 6' above ground level, the condensor is at ground level. You think liquid could get to the compressor intake during off time and cause a heavy load when it starts? Isn't there a mechanism to prevent this?
Professional Member*
The correct charge.
Perhaps you should have read the instructions before calling.
Professional Member
Does the compressor have a factory-installed sound blanket? It's a standard feature for your unit. Read about it at: http://www.djsonline.com/amanarce30specs.pdf
Jabs
Professional Member*
Noise from Compressor
Check for that sound blanket, put isolation pads under your outside unit, insulation the small ref. line where ever possible. Make sure the lines are not touching any part of the house. Have a HVAC contractor check the charge. These items will help the tranferring of the noise to the house but you will still get some noise from that Amana unit.
Blue Fox
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