TL5G fault ?

[Buzzliteyear]

Hello,
I have a TL5g Danfoss compressor in a small clear door bar fridge that the motor cuts in and out every 20 seconds

I have replaced the start relay as contact were burned from it restarting lots of times with last owner

Have check gas and should be fine to run

I have bypass the thermo switch to eliminate that

But the run and start windings are low in ohm's

the should read 14.8 for both start and run

but they measure 9.9 run and 9.3 start

plus when i did have the old points cleaned up on the old start relay
the run coil gets very hot

could the internal windings become damage from stop and starting 100's of times with
old owner ?

thanks for your help

[Brian_UK]

could the internal windings become damage from stop and starting 100's of times with
old owner ?Short answer - yes.

Is it the compressor klixon that is switching the compressor on and off or is it the control side?


Faulty thermostat or wiring spring to mind.

[Buzzliteyear]

Hi, I am guessing it is the internal protection that is switching the compressor on and off

there is no other external switching as i have bypassed the thermo switch

Do you think the internal windings have heated up and shorted out some to reduce the resistance
in the windings ?

If so why didnt the internal fuse stay open circuit longer when it got hot to protect the
main and start windings ?

thanks again

[Brian_UK]

Small compressors don't always have internal thermal links, they tend to use a Klixon mounted in the terminal box to monitor amps and temperature of the casing.

[edit] I stand corrected, just looked at compressor data sheet and it DOES have an internal overload. DOH!

The compressor windings should read 14.5/14.8 ohms on main/start according to Danfoss data sheet, here.....
http://www.ra.danfoss.com/TechnicalInfo/Literature/Manuals/06/TL5G_R134a_220V_50Hz_05-01_Cg42c202.pdf

[Buzzliteyear]

its good to see someone doing there homework....yes i did notice the internal switch

Ok not as easy fix as i planed but will find another compressor to replace this one

I was trying to find a cross reference to that size motor ( 5 cm3) so when I am out on the lookout
I could have a list of possible replacements and choose from

Does this list exist ?

thanks again brian_uk