Trane AC unit problem

[jjbodean1970]

Trane XR13 unit (heat pump), discovered a couple days ago the outside unit wasnt running. replaced the capacitor and contactor a couple hours ago. the outside unit now runs, but it doesnt seem to be cooling.

ideas? i'm running out of the scope of my abilities and need some suggestions before calling the service guy.

thanks,

jeff

 

[jjbodean1970]

additional info: compared to my homes other unit. the unit working properly blows hot out the top, the unit not cooling does not. unit working properly the large freon line is cold, the unit not cooling is not.

compressor?

 

[Rookie2]

Have you tried tripping the breaker off for a minute to just reset everything?

Had you cooled any yet with the unit this year (since winter) or has it been cooling, stopped, and then you changed out parts?

Is it heating?

 

[jjbodean1970]

i had turned the breaker off to replace the parts, but havent tripped it again since repowering it.

yes, it cooled fine until earlier this week, but i havent tried kicking the heat system on.

 

[Rookie2]

i had turned the breaker off to replace the parts, but havent tripped it again since repowering it.

yes, it cooled fine until earlier this week, but i havent tried kicking the heat system on.

Okay, doesn't sound like you could be having the same problem I just got done dealing with. Carry on.

 

[agomez]

pm crazy 88..

 

[jjbodean1970]

heres pictures of everything. additionally, i dont believe that the compressor is running, likely only the fan. i hope i mis-wired something and its a simple fix as long as i havent fried something.

old capacitor showing the 1, 3, and 4 tabs:

wiring on the top of the new capacitor. brown wire goes to tab marked "fan", the 2 orange wires go to the tabs labelled "herm", and the red and purple wires go to the tabs labelled "c":

new contactor wired in. i simply moved individually the wires from the old contactor to the same spot in the new one. its a single pole 30A, 24V:

additional pics:

 

[cruiser88]

You got a digital( lasor) temp? So the suction line is cold, How close to the compressor just is it cold?

Can you even remotely get your hands on the comprssor?

An old trick us HVAC guys do when a compreessor is failing, we add more (in series) start and run capacitor . We do that when an older unit is no longer worth fixing but we may get another season. anyway enough rambling. The best way to determine if a motor is worth a damn is test it with a meter, you got one? If you do I got specs.

How many tons is your heat pump?

 

[cruiser88]

First of all 240v compressor. with a multimeter. First, Check all 3 points against earth. Obviously you shouldnt get a reading on any.
Secondly, Take the 3 points of the compressor and measure between them. 2 of the readings should add up the 3rd so for example the 3 measurements you might get are 6 ohms, 5 ohms and 1 ohm, This is therefore OK as measurements 2 & 3 add up to the first.
On a Three phase compressors all 3 measurements should be the same.
lol I am lazy

I dont think you really wanna test the cap. the way your suppose to.lol but if you wanna know, I am happy to help.

 

[cruiser88]

I was wondering myself if the oil settled and the piston isnt all the way performing, god so many times we have had to tap blasted new units, right off the shelf.

Have you tried tripping the breaker off for a minute to just reset everything?

Had you cooled any yet with the unit this year (since winter) or has it been cooling, stopped, and then you changed out parts?

Is it heating?

 

[cruiser88]

This will help you testing the motor.
brown/white --------> cap
brown --------------> cap
purple (common) ----> L1
black --------------> L2
green --------------> ground
cap.

brown: motor -------------------> cap (terminal labeled "fan")
purple: motor -------------------> cap (terminal "0" or something like that)
black: motor -------------------> circuit board (contactor?)
orange: cap (terminal "herm") ---> somewhere else
red: cap (terminal "0") ------> somewhere else




ask anything, feel free.

also the we has an engineer amung us.....lol I know he is good

 

[Trollhole]

Is the compressor coming on? You need to check that the compressor is coming on before we can go any farther. Compressors have built in low pressure sensors that won't allow the compressor to cut on if there is little to no freon in the system.

Watch out dealing with the cap. It can shock the crap out of you.

Herm= compressor
C=common, contactor
fan=fan

It looks like you have everything connected correctly.

 

[Trollhole]

We need to know if you can hear the compressor coming on a few seconds after the fan comes on.

 

[jjbodean1970]

i dont think the compressor is coming on. i've also decided this is out of my scope and have relented and called the service guy. i'm still under parts warranty, but not labor.

i'll update with the findings, and thanks to all who replied attempting to assist.

 

[jjbodean1970]

def not something i could have either diagnosed or repaired: bad TXV on the inside air handler.

 

[agomez]

Is the txv a circuit board?

 

[jjbodean1970]

its a valve inside the air handler