Mitsubishi Electric Vrf problems with one indoor unit.

[Ian21081974]

Hi Everyone
I have a problem with a
Mitsubishi Electric VRF system.
Model No PEFY-P32VMA-E
Ser No 2K02997
So the this system has 9 indoor units on all the other units hold temp.
But this this one doesnt.
This is the third time something has gone wrong and im not sure why it keeps doing this.
When i have spoke to Mitsubishi in the past we have focused on the lev head.
The head was replaced first time around and was working fine.
About two weeks ago it stopped performing and coulnt hold temp.
So i tried a lev head reset by disconnecting the m net etc and resetting that worked again and worked very well was really chuffed.
But two three weeks down the line the room is not holding temp again but all the other units are.
Does anyone know any common faults ??????
Could it be comms errors ?????
Could it be bc box fault ?????????
Could it be bc box port,comms fault
To be honest im stuck and at the hands of the gods and Mitsubishi

Ian

[Neddy]

Hi Ian,

Have you checked the port address at the indoor and confirmed its connected to that port at the BC box? Check the indoor thermistors are reading correctly. Is it just one indoor connected to one remote controller? Check where the indoor is using the return air sensor from. Ie back of the unit, remote or wall sensor. Is the indoor calling for heating/ cooling or is the return air sensor in a poor location.

[Ian21081974]

Hi Neddy

Back on this one again this is the most annoying fault I think I have ever had so fed up.
Same faults again been speaking to Mitsubishi been getting different ideas keep getting different engineers don't think they believe me or understand the fault or situation im in.
But changed the settings to the thermistor on the controller as well now.
Been speaking again they think the Lev head is Faulty again so ive taken it off and checked the spindle.
they said if its not flush with the oring and driven out when taken off its faulty.
And that it must of been over tightened when put on he said hand tight then 1/4 of turn with spanners the maximum im pretty much I done what I was told but cant be sure.

Can anyone tell me if they have had this problem before ?
Any Mitsu specialists ?
Also does anyone have the correct procedures in there notes for fitting them.
Ie powering down the system ie cond indoor unit bc boc etc.
Please help ahhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhhh lol
I need a pint soon
peace my rant is over lol
please help

[r.bartlett]

Tim Keywood