Mitsubishi Slim PUH-5YKSA

[jonesy_87_]

Hi everyone,

I have a question for the Mitsubishi gurus..

I have the above model ducted system at home. Have been having problems since last night with it running on heating.

Unit starts, compressor kicks in, indoor fan runs - Unit will run for about 10 minutes and then will shut off. Every now and then though, it will run for 10 or so minutes, indoor fan will turn off, compressor will keep running and indoor fan will eventually start back up and it will display 'Standby' next to the heating icon for several minutes after until everything shuts off again.

I am an aircon tech (though most of my experience is with BMS, package units, etc) and don't know too much about the Mitsubishis.



Any advice welcome,

Cheers

[jonesy_87_]

Also, brief history..

18 months ago I got a P8 error. I found a cracked pipe and repaired it, regassed, etc. Since then has run perfect.

When I press 'check' on the indoor controller twice, the P8 will start to flash - unsure if this is a new P8 or the old code stored as history? The main C/B has been reset and still see the P8 only when I double press the 'check'.

Also, in the first 10 minutes when it runs, it still seems to warm up ok - Havn't been able to get any readings as I need to wait for daylight tomorrow.

[Denni]

When I press 'check' on the indoor controller twice, the P8 will start to flash - unsure if this is a new P8 or the old code stored as history?

Yes! It is "Error code history".
See screenshot of TECHNICAL MANUAL PAR-21MAA (for exaple) below:

2014-06-17_144620.jpg

[jonesy_87_]

Yes! It is "Error code history".
See screenshot of TECHNICAL MANUAL PAR-21MAA (for exaple) below:

2014-06-17_144620.jpg

Awesome, appreciate that. Cheers

[Denni]

Unit starts, compressor kicks in, indoor fan runs - Unit will run for about 10 minutes and then will shut off. Every now and then though, it will run for 10 or so minutes, indoor fan will turn off, compressor will keep running and indoor fan will eventually start back up and it will display 'Standby' next to the heating icon for several minutes after until everything shuts off again.

Trouble occur now?
If "yes" - what is the model number of your Indoor Unit & Remote Controller?
Start the TEST RUN mode (See p. 42 of "Technical Manual PAR-21MAA" on link bellow). This mode show "liquid pipe temperature". Value of this temperature may indicate system status (Trouble/Normal).
https://www.sendspace.com/file/a5mvpu
(Press "Click here to start download from sendspace" button for download)

[jonesy_87_]

Trouble occur now?
If "yes" - what is the model number of your Indoor Unit & Remote Controller?
Start the TEST RUN mode (See p. 42 of "Technical Manual PAR-21MAA" on link bellow). This mode show "liquid pipe temperature". Value of this temperature may indicate system status (Trouble/Normal).
https://www.sendspace.com/file/a5mvpu
(Press "Click here to start download from sendspace" button for download)

Will check indoor model number tomorrow but remote controller is the PAR-JH050KA.
Had a quick look through the link but it seems to be more specified to the newer controller.

Thanks

[install monkey]

http://www.mediafire.com/view/ic25lq...PEHD-16-25.pdf
click on link for service manual- the p8 error might be the last stored fault- when u run it in heating does it flash up p8? check normally on old mitsi units they dont have a lp switch they wait till the comp overheats or if the room temp doesnt change by a few degree's every few minutes, check filter is clean- run it in test heat and also test cool to see what your coil temp is- (where room temp is on remote) sometimes this is a figure as opposed to tru temperture- in that case cooling mode u want to see a value of 1, heating mode u should expect it to reach 12 - standby is shown on the remote until the coil temp reaches 30 deg then the fan will speed up a lil- if the coil temp drops then it can show standby again-
gas charge being low can cause the same issues- mitsi were renoun for leaks on the discharge pipe sensor pocket-

[jonesy_87_]

http://www.mediafire.com/view/ic25lq...PEHD-16-25.pdf
click on link for service manual- the p8 error might be the last stored fault- when u run it in heating does it flash up p8? check normally on old mitsi units they dont have a lp switch they wait till the comp overheats or if the room temp doesnt change by a few degree's every few minutes, check filter is clean- run it in test heat and also test cool to see what your coil temp is- (where room temp is on remote) sometimes this is a figure as opposed to tru temperture- in that case cooling mode u want to see a value of 1, heating mode u should expect it to reach 12 - standby is shown on the remote until the coil temp reaches 30 deg then the fan will speed up a lil- if the coil temp drops then it can show standby again-
gas charge being low can cause the same issues- mitsi were renoun for leaks on the discharge pipe sensor pocket-

Cheers.. I have a feeling it may have a leak. Ran it last night in an attempt to get a bit of heat from it.. When fan stopped, standby disappeared (as comp ran) and once the fan ran again it went straight into standby - Indoor coil isn't reaching temp with fan running.
Will check gas once the sun comes up and update.

[jonesy_87_]

Quick update..

Looked over everything today, came to the conclusion that I had a partial restriction on the evap inlet. Reclaimed gas, reverse flushed system , new dryer, 500 micron vac and regassed and it is running beautifully.

Appreciate all the help!