control v/v and coil mismatch

[nanuuk]

To make a long story short here's the problem.
I have 4 /27 ton coils made by AREO COIL model #MH2-2408-120-3AXG-5 mated with Danfoss ICAD 600 Danfoss motorized control valves. The problem is that the tube diameter is to large 1" on these coils this is an DX system. The valve modulates liquid feed via a sensor which reads super heat in the suction line but because of the amount of liquid comming out of the coil ( BRINING) into the suction line these valves for the better word are confused because there just is no super heat to read so they are all over the place.So we just took them off line and are now using the by-pass vaves for our feed at a 1/4 turn open each what I get in the end is a 2 degree T.D. and my transfer tank dumps on average 60 to 100 times daily which is better than what I get with the control vavles. Now without having to change the control valves or the evaps or go to a pumped liquid system does anyone have a sugestion on what to try. I can go into more detail on the whole dilema if need be but I thought I would just throw this out there and see what kind of response I get with the info given. Thanx for the ear.

[Brian_UK]

What is the system serving, refrigerant type and evaporating temperatures please?

We assume that the control parameters were all set correctly.

[nanuuk]

The system is serving a low temp cold storage room which is 1,125,164 cu ft in size. the medium is ammonia and we like to see temps at -5f. We get this temp but to get any lower we have to wind up the engine room balls to the wall. We have had all sorts of suggestions of what to do from putting in a pulse v/v which opens and closes at set times for the liquid feed to modifying the distributor at the coil.It was also guggested to make the suction riser smaller in diameter to create more valocity. We moved the sensor around with no luck so now we want to do something else but I don't want to this to go any farther south on us than it has already. I can afford to loose one coil this time of year but in the warmer months thats not an option.