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joerocket
05-08-2014, 10:38 AM
Hi All. Need some help. I have a Daikin unit model RUR15NY1 (outdoor unit) and FDR15NY1 (indoor unit) using R410A. I am having icing issues. My steps so far:-

1) after finding the evaporator coil fully iced, i turned off the system for a day.
2) turned on the unit on day 2 and checked. No more icing at evaporator but suction pipe and accumlator at condenser side is totally iced. set temperature able to achieve. Checked low side pressure is 90psi and high side is 380psi. I did not charge anymore gas because the suction pipe and accumulator are already icing.
3) The running amp is at 27A, very close to the max rated which is 26.4A. Therefore not adviseable to charge further gas.

So now i need the HVAC gurus to tell me what i should do next. BTW i am from Asia where the average ambient temperature is from 25 celcius to 35 celcius with humidity around 80 to 90RH.

RANGER1
05-08-2014, 11:14 AM
Joe,
Suction is below 0 deg C
check clean indoor unit filter & coil if necessary, check airflow
check condenser is clean & airflow

PRESS
05-08-2014, 05:27 PM
Is this a new or existing installation? If its new you may have to check your piping lengths and recalculate the amount of additional gas. As ranger has indicated you are running below 0DegC. If it is an existing installation then you have to follow ranger's recommendations above.

joerocket
06-08-2014, 05:30 AM
Is this a new or existing installation? If its new you may have to check your piping lengths and recalculate the amount of additional gas. As ranger has indicated you are running below 0DegC. If it is an existing installation then you have to follow ranger's recommendations above.

Mine is an existing installation. I did cleaning earlier on evaporator air filters, coil and condenser coils. I am suspecting 2 things

1)maybe the evaporator coil is choked causing low heat exchange
2) Thermal expansion valve not operating properly. Is there a way to check it?

Keza
07-08-2014, 08:32 AM
Check your airflow, as above threads have stated.
If your fan motor is not running (faulty capacitor or belt has broken) then you will have a complete ice down of the suction line etc, because there is no heat rejection.

joerocket
09-08-2014, 04:38 AM
hi all

my airflow at evaporator is good. in fact I removed the air filter and ran the system and here is the diagnosis-
suction pressure 95psi
liquid side pressure 350psi
compressor running amps 30A (max rated 26.4A)
no more icing noticed in first 4hrs. I placed back another filter from another unit and monitoring for next few days.

But here are my questions-
evaporator side temperature is below 0deg C. is it good or not.
compressor running amps is over and above rated amps. ok or not