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anil130
25-06-2015, 04:35 PM
hi friends, i have installed Mitsubishi VRF but indoor units are not cooling sufficiently,
could any body help me to figure out the problem.on the remote controller there is no error shown, phase on the indoor is also ok.below are the model no of IDU and ODU.

Model no of ODU:PUHY-P450YHA(-BS)

Model no of IDU: PEFY-P250VMH-E x 2 Nos

Deano240
25-06-2015, 09:48 PM
Have you checked the refrigerant charge? What pressures are you getting? What temperatures?

anil130
26-06-2015, 03:31 AM
@Deano240 (http://www.refrigeration-engineer.com/forums/member.php?33743-Deano240): yes i have added the refrigerant charge. i am getting only 18 Ampere on cooling mode and on this Amps : high pressure = 450 and low pressure =115.but after few minutes it comes to 15 Ampere and on this Amps: high pressure = 350 and low pressure = 110.now its running on 12/13 Amps.hope this data works.

install monkey
26-06-2015, 08:06 PM
are u clipping the comp current on the leads or the incoming power to the outdoor?, did you pressure test with ofn (nitrogen) prior to powering up?
was nitrogen used to purge whilst brazing?
use the dipswitches on the outdoor sw1 to read compressor freq, maybe set sw1,1 on indoor (address pcb) to use the thermistor in the remote controller instead of the return air thermistor. (if its in the conditioned space)

abp32
27-06-2015, 09:30 AM
whats your air off the cassettes it should normally be between around 10oc

abp32
27-06-2015, 09:31 AM
and what refrigerant do they run off

anil130
29-06-2015, 03:31 AM
are u clipping the comp current on the leads or the incoming power to the outdoor?, did you pressure test with ofn (nitrogen) prior to powering up?
was nitrogen used to purge whilst brazing?
use the dipswitches on the outdoor sw1 to read compressor freq, maybe set sw1,1 on indoor (address pcb) to use the thermistor in the remote controller instead of the return air thermistor. (if its in the conditioned space)

Dear Install monkey: yes i have tested the pressure with Nitrogen.but what i did yesterday, i just turn off all dipswithch off of SW1 and its working fine.