Kolpak Arctic Fox Evaporator Coil and KE2 Controller
Anyone have any experience with this setup? I am trying to diagnose whether or not I have a bad Electronic Expansion Valve (EEV) or an issue with the KE2 controller on this walk-in-cooler. I'm getting a HSH (High Superheat) alarm.
I put my eyes on this particular setup for the first time yesterday and it's kicking my a**. After doing some research, I understand what all the components (KE2 controller, KE2 remote display, electronic expansion valve, temperature sensors and and transducer) do, but before I call technical support, I'm trying to get all my ducks in a row so I don't sound like an idiot when I describe what's going on with this system.
I haven't checked resistance across the EEV leads yet, but I plan on doing that tomorrow. Also, I plan on manually operating the valve to check that it's operating properly.
FYI, this system was installed by "others" and it's been running without any obvious issues for 2-1/2 years, but I wouldn't be surprised if I have a restriction at the EEV (trash, moisture, oil, etc.) based on the issues the system is exhibiting. Thanks!
First... what you working on man?
Walk in obviously, but prep room, storage, meat, etc?
How many evaporators? 1 condensing unit?
Brand of condensing unit?
Is there a liquid solenoid on this or just the EXV?
Where I would start, would be to confirm that the KE2 controller is seeing the correct info. If either the transducer or the suction line temp sensor are incorrect then there is no way the EXV will modulate correctly.
Watch the system operate while you are tapped on and monitoring actual pressures, temps, and superheat and see what these readings compare to the what the controller is seeing.
Make sure you have a clear sight glass and no temp drop across your liquid driers.
It’s a medium temp kitchen walk-in-cooler at an elementary school.
One 2-fan evaporator coil with EC motors.
Pump down R-438A system on a Kolpak condensing unit with high/low auto-reset pressure controls, Sporlan head pressure control valve, drier, receiver, typical stuff for a walk-in-cooler.
I don’t know what the controller is seeing. It was never given internet access, so I can’t access the web page with sensor and other data.
With your chrome heart shining in the sun, long may you run.
You should be able to get into that controller relatively easily.
Most KE2 controllers you hold down the left and right buttons for a short bit to access a quick menu which shows most inputs.
If its locked, you'll have to gain access to it somehow and will need to contact KE2. Their tech support is pretty good..
If you get the system to run, you could unplug the EXV while you observe. ExVs are stepper motors and dont move unless they're called to. So if you remove power, they stay where they're at until they're commanded again by the controller
Yeah, it runs as long as the EEV is feeding the coil. Several times, the valve has stop feeding and causes the condensing unit to pump down and cycle off on low pressure.
Does this look like its been overheating?
With your chrome heart shining in the sun, long may you run.
The whole kit (valve body, stepper motor with wiring harness) on order next day air early AM. FYI, suction line temperature, suction pressure and resulting superheat were on point when the EEV was feeding properly, but then things would quickly deteriorate once the EEV became erratic. One minute it was feeding and throttling, the next minute it would stop feeding altogether, resulting in pump down.
With your chrome heart shining in the sun, long may you run.
Ever get into the control and see if gas is set right or other measurements?
Yes, I did check which refrigerant and it was set for R-448A and the right stepper motor. All other parameters were set correctly.
I am happy to report that a new valve and stepper motor were installed today. Cooler is running and cycling on/off. The only question unanswered is what caused the stepper motor to burn up?
For comparison, here are photos of the old and new stepper motor.
With your chrome heart shining in the sun, long may you run.
I believe that you don't want to use a solenoid on systems with an EEV. Pretty sure the KE2 will close the stepper and that acts as your pump down. This has nothing to do with the motor failing, just an FYI. It does look like overheating may have burned off the coil windings varnish and it shorted. Did you measure the resistances between the windings/case?
Reply
Originally Posted by VTP99
