Mitsubishi MS-17KVE1 - Weird Compressor

[vmcacador]

Hi!

I would appreciate some help on this subject.

We are servicing a Mitsubishi air conditioner model MS-17KV E1.

In cooling operation the unit seems to work fine, Power supply OK, working pressure is normal (55 psi / R22), blower working fine, compressor current starting at 11A going as low as 7,5A and then it rises to about 9A. Compressor head temperature reaches almost 80ºCelsius.

The equipment runs for about 40 min, then it stops nad we can´t get it to work again, after a while compressor started for a second but it stoped again. Starting capacitor at 54uF (I think it´s OK).

Would you say I have a busted compressor? How could I be sure?


Best Regards
Vitor Caçador

[GXMPLX]

Could be many things if I had to guess the compressor overload is shuting it down. This is easy to check!

Again guess it may have high discharge temperature, don't measure head temperature but discharge 15 cm away from the discharge valve.

If you want better diagnostics and hot have us(me) guessing, then you have to measure at least also high pressure and suction superheat.

And the compressor model!

[vmcacador]

Hi!

Thank you for your reply, I was going to measure high pressure and superheat but unit stoped working. The compressor makes a "ratling" noise sometimes, changing it is madatory...

[Brian_UK]

After the compressor stops next time check the motor windings to see if the internal overload has gone open circuit.