Mitsi Vrv 7 Indoors none will heat or cool

[moondawn]

hi all.

was wondering if anyone could give suggestions on this new install that is being commissioned.

The outdoor is PURY P200 YMF-A

has 7 indoor units. the gas charge is 10.5kg +6.4kg Additional. so total 16.9kg i have 1kg left to add to the system.

I have ran the system firstly on heating and have no heating at any indoors the coil temps were showing about twelve degrees. I then have tried runing it on cooling and nothing happened on that either. i left the oc with power to it for over twelve hours and have since tried it . the coil temps have gone to about 20c. there has two prelimenary errors occoured on the system. one is 1402 i think high pressure sensor abnorm. and 1600 which is prelim refrigerant overcharge.

i have left the system running overnight to try to get it to bring an actual Fault code up not a prelimenary one.

any imput is appreciated thank you
moondawn.

[moondawn]

hi i added it through the liquid ball valve after i had vaced it. then i opened the ball valves. i charged as a liquid.

thanks moondawn

[Thermatech]

The system is R2 so it has a B/C box.
Did you set up each indoor unit with correct port address to match pipe connections ?
Check the wiring loom to the B/C solenoid valves has not been disconnected & confirm heating solenoid valves are energized for each port.
If the outdoor unit is running with good discharge pressure in heating then something is stoping the hot gas getting to the indoor units.
6kg is not a large trim charge so system must be compact with relatively short pipe runs.
If the total capacity of the indoor units is more than the outdoor size 200 then heating performance will be poor if you ask all to run flat out in heating.
Try running one at a time in heat test mode.
If one B/C solenoid valve is locked open or one indoor unit LEV valve is locked wide open then you will get refrigerant bypass so by running one indoor unit at a time you can track this type of problem down.

Update with your findings.

[moondawn]

hi thermatech
yes sytem has BC box all port and address are all ok. all solenoids are opening on bc box . i have checked this on the dipswitches it tells me solenoid b opens i think on each port of the bc box.
it is smallish runs 80 metres of 1/4 pipe 22 metres of 5/8 pipe and think it was 16 metres of 3/8 pipe. the system has a 63 3x 20s and 3x 32s on it total is 219 index.
i have tried with three units working and still does nothing??

[Thermatech]

Ok
The outdoor can tell you what valves in the B/C are being asked to open but is the 240v actually getting to the coil ?
The only way to be sure is to put your meter on it.
A quick check is to un plug & then reconect each valve at the circuit board, klick klick tells you its working.

Thing is you seem to have high pressure at the outdoor unit for the prelim hp fault. So why is that hot gas not getting to any indoor unit ?
Its ether running up to a shut valve or there is such a large bypass open to suction that its all getting dumped back into the suction.
In heat only mode the hot gas goes straight to the B/C on the discharge tube. Is it still hot at entry to the box?
Then through the hot gas solenoid valve to the indoor unit. Is the gas tube hot at the indoor unit ?
Then out of the indoor unit throuugh the LEV valve as warm liquid. Is the LEV valve opening up ?
Then back to the B/C box & through the subcooler circuit. Is LEV 3 opening up to allow the subcooled liquid to flash off back into the suction line.
Then back to the outdoor unit. What pressure / temp are you getting at the outdoor suction service valve ?
A shut valve at any of the these will prevent refrigerant flow any further.
If you follow the hot gas arround the system you should be able to find the problem. I suspect a blockage or shut valve stopping flow.
LEV valve 3 at the B/C is a prime candidate. If it does not open then there is no way for the refrigerant to flow back to the outdoor unit which looks at the low suction pressure / temp & just ramps compressor down to tick over speed.
Make sure its plugged in at the circuit board board & look at the temperature each side of it to see that its allowing refrigerant through.
But remember that as you have had the system running for some time now if there is any blockage / shut valve there will be a lot of stored liquid traped behind it which will now make the system look short of gas.
If there is a hot gas to suction bypass at the B/C box it will be making excessive noise this can be caused by any one gas solenoid valve jammed open.

Let us know how you get on.

[Thermatech]

Ok
The outdoor can tell you what valves in the B/C are being asked to open but is the 240v actually getting to the coil ?
The only way to be sure is to put your meter on it.
A quick check is to un plug & then reconect each valve at the circuit board, klick klick tells you its working.

Thing is you seem to have high pressure at the outdoor unit for the prelim hp fault. So why is that hot gas not getting to any indoor unit ?
Its ether running up to a shut valve or there is such a large bypass open to suction that its all getting dumped into the suction.
In heat only mode the hot gas goes straight to the B/C on the discharge tube. Is it still hot at entry to the box.
Then through the hot gas solenoid valve to the indoor unit. Is the gas tube hot at the indoor unit ?
Then out of the indoor unit throuugh the LEV valve as warm liquid. Is the LEV valve opening up ?
Then back to the B/C box & through the subcooler circuit. Is LEV 3 opening up to allow the subcooled liquid to flash off back into the suction line.
Then back to the outdoor unit. What pressure / temp are you getting at the outdoor suction service valve ?

If you follow the hot gas arround the system you should be able to find the problem. I suspect a blockage or shut valve stopping flow.
LEV valve 3 at the B/C is a prime candidate. If it does not open then there is no way for the refrigerant to flow back to the outdoor unit which looks at the low suction pressure / temp & just ramps compressor down to tick over speed.
Make sure its plugged in at the circuit board board & look at the temperature each side of it to see that its allowing refrigerant through.