Daikin EWLD235J-SS (McQuay Compact line) chiller problem
I'm registered here for a long time ago, but this is my first post here.
Have a problem with condenserless Daikin chiller EWLD235J-SS (Daikin branded McQuay Compact line chiller), single circuit, with Frame 3200 compressor.
Air cooled remote condenser, ~15 meter liquid line, no receiver, plate heatexchanger evaporator, Danfoss EXV. The chiller is new, have been installed about one month ago.
Before this unit there was another Daikin unit with freezed evaporator and broken compressor.
Condenser remain the same, some kind of cleaning of tubes have been made by installer.
There are two problems with this chiller.
First one - is nonlinear increasing of compressor capacity.
When controller start to increase the capacity of compressor, current consumption increase very slowly. Its change from 52 to 70 Amps during capacity from 25 to 97%, and sharply increases up to 102A at 100%. After it chiller goes to High Pressure alarm or Low pressure alarm.
If I trying to increase Load Up Pulse Length from 0.3 s to 0.4 or 0.5 s, compressor increase its capacity more linear, but at some moment during loading up, low pressure is going down and unit is going in LP alarm once again.
Looks like expansion valve does not work correctly. There is a sight glass on EXV body, but it installed to close to compressor so I cant see anything on it.
Second problem - is a strange noise from compressor. When this sound is appear, low pressure is dropped down quickly and unit goes in to Low Pressure Alarm.
Here is the video from site:
Chiller start from 01:07.
This sound can be heard from 09:08
Sound is like whistle on a boiling kettle. I have no idea what comes first - strange noise or low pressure drop.
EXV unexpected closed?
I would appreciate any ideas about possible causes of these problems. Thanks in advance.
Sorry for my English.