Error Code P6 00

[mr_slim]

Hi all...

I'm having some problems with a Mitsubishi Mr. Slim ductless air conditioner unit:

wall unit part #pk18fk3
condenser part #pu18ek1

The problems are as follows:

1. Only half of the a/c blows cold air (the right side of the unit). The other side blows semi-cool to room-temperature air.

2. During intense thunderstorms (usually at night), the unit completely shuts off with an error of P6 00.

We have two other similar units that blow cold air from both sides, and thunderstorms do not affect them. Does anyone here have any ideas as to what might be causing these problems?

Thank you!

[hyperion]

P6 refers to "Freeze protection" in cooling mode. System could be short of gas, particularly as you mention that cooling is onlt happening on half of the air handler.Check the joints and to be certian of the gas charge, reclaim all of the gas and weigh it. f it is less than the total charge, carry out OFN leak testing, repair the leaks(s) vac it out and re-gas charge with the correct amount of refrigerant. Not sure why the thunderstorms should affect the unit. Sort out the potential gas problem first and post back.

[rude]

Check filters 1st. Then address your gas charge.

[mr_slim]

Filters are clean.

[superswill]

Filters are clean.

then as said decant refrigerant and check against manufactures data plate,also take into account any additional charge

[mr_slim]

Our tech reported the following:

"...the refrigerant charge was recovered and the system evacuated. Then it was filled with a fresh charge to factory specs. There was no change in the performance of the unit..."

In addition, the unit failed again with the same error. I had to turn it back on. There were no thunderstorms last night, but the humidity is pretty high this morning (94%).

Again, neither of the other two a/c's went out.

[mr_slim]

One other thing: the code on the a/c this morning when it went out was:

P 800.

[sinewave]

Is the airflow through the Coil OK?

Is the Fan performing within specs, rotational speed, free of debris etc?

Are the vanes open and not restricting air flow?

Check for office staff who may have shoved cardboard etc up through the louvers to stop darfts?

[frank]

I had a similar experience with a Mitsi Mr Slim cassette system from new.

It turned out that the distributor was partially blocked by over zealous brazing leading to a starved evaporator and low suction pressures despite the charge being correct.

Your description of the indoor unit only blowing cold from 50% fits the bill exactly.

Take some temperatures on the pipework inside the indoor unit and outdoor unit to confirm.

Seems like the guy that built my bit of kit had a bad Friday or Monday - well the factory is in Scotland!

[mr_slim]

Thank you all for your help. Here's what I got from the a/c techs:

"Today per recomendation of a Mitsubishi factory tech, we backflushed the evaporator, screens and service lines with nitrogen. There was no noticible obstruction and when recharged it worked.
At this time we can only assume there was some kind of restriction that caused P6 code."

I might also add to this that both sides of the a/c are within four degrees of each other.