adjustment of parallel SPORLAN SORIT-20 EPRs

[racktech2008]

Another one for the supermarket rack lovers:

I´m trying to adjust the operation of two SORIT-20 EPRs connected in parallel, that set the evaporator pressure in a rack circuit. According to the instructions I found in the rack log, I´m suppose to initially "reset" both of the EPRs by turning their adjustment screws all the way in, and then gradually turn them out, a little bit at a time, simultaneously. At first, both of the EPRs get similarly cold, but after a few hours, one gets colder and the other noticeable warmer. I´ve repeated the same procedure several times, with the same results.
Both inlet pilot screens are clean. The EPRS were recently overhauled: new pistons, sleeves, O rings, springs and gaskets. Solenoid coils were not replaced but seem to be working all right. Any other recommendations?

[Brian_UK]

Are you setting the valves in accordance with the Sporlan instruction/installation documents?

Are you using a pressure guage when setting them or just hoping that you have adjusted them the same amount?

[750 Valve]

so you have 2 sorits in parallel on the ONE suction line? As Brian suggested are you going by the pressure, personally I would reduce the evap load, suction stop one at a time and set each one individually using a pressure guage at the SST required for the cases or rooms on the circuit.

[racktech2008]

Thank you very much for your interest.

I´m indeed checking the evaporators pressure with a gauge at the EPR inlet port while making the adjustments.
I think you just gave me an adjustment procedure that might solve my problem: close the suction stop valve on one of the EPRs, forcing all flow through the other leg of the parallel configuration, and proceed to adjust the pressure on the EPR on this leg to the desired value. Then redo the same thing to the other leg. I´ll try it and inform you of the results.

[750 Valve]

no worries mate, should work a treat, just monitor each valve for a while to be sure they stay where you set them, I've found SORITs to be good though.. an ORIT - well, different story

[racktech2008]

Thank you fellows for your helpful hints. I proceeded as instructed by your comments, initially closing one of the legs of the parallel configuration in order to adjust the SORIT on the opened leg. Then repeated the procedure for the other SORIT. They seem to be working all right now. As you said, while making the adjustments, it´s important to wait until pressures get stable.

[750 Valve]

Glad to be of help to you