Help with conventional rack available cooling capacity

[SmileyMan007]

I have been asked to determine the available cooling capacity on a conventional Tyler rack because the supermarket is considering a remodel. The engineer I usually use is unavailable and I need to provide information before he returns. I have the BTU/ft ratings on the cases and the compressor tonage. Can I determine the current load and the available load with this information or do I need additional information? How do I calculate the above? If additional information is needed, what info?

[smilies]

You already have the case loads, now figure out the BTU's the compressor is rated for at the SST the cases will run at. Get the condenser info and figure out its rejection rate.

[SmileyMan007]

Thanks for your help! Do you have a layman's term mathmatical equation for me to use once I obtain the rest of the data? Or do you know where I can find one?

[750 Valve]

mate try doing this....

1. find out the tech data on all your cases from the mfg - get the heatload and the SST the cases require - these will all be published by case mfg
2. get the room heatloads - most customers have specs on SST's for rooms - if not just do a heatload calc and select at an average td to do the job
3. add them all up to get a total and note what the lowest sst is
4. get comp model numbers and look up mfg data for lowest sst - or if it is a multi suction group rack then lowest sst on each group
5. add up total comp duty to get what rack will do - compare this to case and room total to see what extra capacity you have
6. get comp thr from mfg for rated conditions or add input power to comp refrig capacity, total them up and you have total rack THR
7. get ratings on cond from mfg - most give a rating at 1KTD, now apply customers specs for cond TD to find condenser's capacity. If no specs divide THR by cond capacity at 1ktd, this will give you the TD that the cond will perform the required duty at
8. grab a beer and relax - you just finished.