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View Full Version : Right side of supermarket display always warmer ? Any thoughts?







kengineering
10-05-2016, 12:17 PM
Hello all, OK so I've been doing some in house testing on our grab n go supermarket display cases with ASHRE-72 my guide and over the years I've noticed the left side temperatures (customer view) are always colder than right side.

I have my theory but would appreciate your comments including possible remedies.

As always, Thanks for your input, Kengineering

chemi-cool
10-05-2016, 04:29 PM
I think you have to be more specific apart from " left side temperatures (customer view) are always colder than right side. "

Are they being fed from the same source with the same length of pipe?

kengineering
10-05-2016, 10:08 PM
OK a better description. I'm currently have a 180 cm wide 160 cm tall open front with closed insulated glass ends. Medium temperature fresh meat display/merchandiser with a deck and 4-shelves. It contains one six circuit evaporator fed by a Sporlan balanced port TXV. Two-200 mm fans complete the job. We have no customer complaints. However like I said the right side temperatures ,on every shelf are a bit warmer. Every case I test has this condition. I suspect some phenomenon involving Fan Blade rotation.

Rob White
11-05-2016, 01:47 PM
.

The majority of cases I have worked on have baffles of
some sort to guide the air and if the evap was long enough
these would be per fan section so a 12" case might have
at least 4 maybe as many as 6 fans on it and each one has
its own section of evap for the air to pass through.

Fan rotation would, if you are correct push the air to one
side or the other but not if the case is designed correctly.
Most cases I have worked on are air flow tested with smoke
to prove the correct flow and it is something we can do
and I have done it countless times.

I'm not sure if I have seen the same results as you have, but
I'm prepared to accept that anything is possible in this big and
wonderful world we live in.

Regards

Rob

.

chemi-cool
11-05-2016, 09:26 PM
The side close to the TXV should be colder.
Thats where superheat starts so at the outlet it will be hotter.

Glenn Moore
14-05-2016, 10:28 PM
Hi Ken have you a picture of the coil in situ, as the coil design , fan positioning , and evaporating condition along with the superheat set up of the expansion valve will all have a bearing on how the cabinet works.

kengineering
17-05-2016, 08:08 PM
Yes all true, I've been around these things for decades. The movement of cold air is a tricky thing, especially when dealing with air curtain type grab and go's. Our customers have never complained, I was just throwing it out there as testing is heating up. All the DOE reg's along with the EPA's refrigerant de-listing looming in the very near future makes for a challenging future for my company in both Engineering and Finance.
Thank s for the replies.

monkey spanners
17-05-2016, 09:05 PM
Just an idea, why not try a opposite rotation fan motor and corresponding blade on the right hand side to see if it makes a difference?