Multi City

[spikybm]

Im having a problem with a multi city hocked up to four fan coil unit.Out of four three indoors are cooling an the fourth is only blowing room tempreature air .Have changed all the indoor sensors and still no cooling.Has anybody come across this???Any solutions.

[Brian_UK]

The fourth unit has a fault with it somewhere.

Expansion valve perhaps.

[spikybm]

have you worked on this type of system before its running on r407 and the expansion valves are screwed on not clip.we tried adjusting the valve both manually an through the Mitsubishi maintenance tool.With no change in tempreature???

[icecube51]

do you have done a check up whit the service tool and is the outdoor-unit recognizing all 4 units?
are the given parameters ok?
what are the sensors telling you?

[Thermatech]

Y series heat pump system
No 4 unit has fault with LEV valve , indoor circuit board or blocked liquid line strainer.
R2 heat recovery system
As above & or also incorrect branch address setting for BC port connection.