Equalisation line

[freezy]

Hello

When installing an evap in a coldroom with a TEV on top of the coldroom, can the external equalisation line be burnt into the suction pipe on top of the coldroom after the oil trap on top. I know it should be near the phial but there is only about 600mm difference so the pressure will be the same and it's easier to do?

Anyone any thoughts?

[Slatts]

In the grand scheme of things, it probably won't make a lot of difference.
You'd loose some accuracy in the response of the valve due to the pressure drop. When the oil trap started to fill with oil, the pressure at the equalizer line would drop, which would tend to cause the valve to open and flood the coil with more liquid.
This is interesting and something that I haven't given any thought to before. If the oil trap fills, causing the equalizer pressure to drop, the pressure on the back of the power element will drop, causing the valve to open, increasing the flow into the evap, causing the oil to be swept out of the trap, causing the pressure drop to disappear and the system to return to normal. At the same time it'll help get the oil back to the compressor. Of course, you increase the risk of getting a slug of liquid back to the compressor as well.
I was going to tell you to fit the equalizer just after the bulb, now I'm not so sure if it's not worth trying it your way.
Anyone else got any thoughts?

[Rickyjb64]

For many years I have been working with fruit gas stores and the TEV is always put on the store roof due to inaccessibility when loaded and sealed. My findings are (after temp / press comparisons) that there is an insignificent if any,temperature / pressure difference in the short distance between the cooler outlet and new position of the TEV usually less than 1m with the valve functioning as designed. This said...due to the nature of the standard installation I am involved in which does not facilitate the use of an oil trap I would concur with Slatts as to the reaction of the system so I would go ahead with your idea.
Remember to insulate well the phial and the TEV outlet pipe to the distributor to retain duty and reduce sweating. Good luck.

[sean1]

straddllle unit?

[R1976]

aaaaaaaaaaaaaaaaaaa

[R1976]

aaaaaaaaaaaaaaaa

[freezy]

thanks for the replies.



I may have mislead you with the oil trap. It is actually a p trap on top of the riser from the evaporator to stop liquid flooding back to the evap. Now I've come to think about it, I am now pondering my position for the phial. It is strapped to a pipe in the evap that is not strictly horizontal(about 30 degree angle) as this is the only place it can go, as the pipe drops down off the evap then turns forward and then up through the roof. Is this 30 degree angle there to provide a slight rise where oil will not sit?



Also, as I have a p trap on the roof then will oil sit in the horizontal pipe on the roof of the coldroom where I have the equalisation line connected, and will this affect the pressure?

Here's a sketch