Blind Cold room specs help

[frostedflake]

Greetings Engineers from all over!!

Once again i bring my lack of knowledge and my willingness to learn before you , this time I was assigned to recondition two old cold rooms left out of service for about 10 years.

The good thing is that both rooms look refurbishable, the bad thing is that i have not found any specs or labels as for the system efficiency/operating parameters (really rusty and dirty units no labels).

so far this is what i have found out (since i have no power source yet to start the units):

room dimensions: room A) w 3.30 x L 2.70 x h 5.50 mts 25 cm wall thickness, room interior is mosaic covered.
compressor brand/model: Hermetic 3ph 220v Tecumseh AV5558G (58,000 btu)
evaporator fan motors specs: two 1/2 arrow(axis) 1075/1100 rpm. motors with
with 4 blades 16" each.
piping length and size: 28 mts 1 1/8 suction and 1/2 liquid line with ten 90º fittings each line.
desired operating system start/stop temperatures 4ºC/8ºC for fruit storage.

fan motors both evap and cond seem to be ok just need to replace their capacitors and a good oiling, compressor seems to be ok too but i'm wondering if this model needs a potential relay being 3ph 220 5 ton, i checked on tecumseh's online catalog but failed to find my compressor model.
i also managed to figure out the system refrigerant by taking the p/t... seems to be R22 (system off, suction line pressure 130 psig at 23ºC).


The owner has no technical info for me, other than the operating temps and the product to be stored...

and now all the data i DON'T have:

evaporator and condenser brand/model/capacity, reciever tank model/specs,
liquid line filter dryer specs, default system refrigerant type and charge, low pressure switch, defrost timer electrical power supply.

to get this cold room going so far i have requested the propper electrical installation to be ready and i have cleaned the evap/condenser units as the interior of the cold room (real mess).



So far (with the use of coolpack) i have calculated a 17.5 KW system efficiency
with an evap temp of -6ºC with a 5K superheat and an indoor relative humidity of 65% at an operating suction pressure of 255 Kpa.

hope not to be getting too ahead of myself there...

what else do i need to know before starting this cold room?
I was planning on making an acid test only since there are no gas leaks.

and once i get the cold room running should I:
Measure superheat at TXV evap bulb looking for a 3 to5k sperheat according to sporlan superheat charts.
check for the propper air flow evap/cond fans.
check for my suction and discharge pressures to get superheat and subcooling. check for system amp rate.

i'm pretty sure i'm missing a lot, and if you need more specs to try to help me please feel free to ask.

thanks in advance!

[Brian_UK]

You seem to have identified the gas, did you also check the expansion valve for a data plate?

Don't worry too much about getting the superheat correct until the room is down to the design temperature and the system has balanced.

Also, don't try and get to design temperature straight away, bring the room temperature down slowly.

[frostedflake]

thanks for taking the time to read my post and for the good pointers.

i found no label or serial number, model or maker on the TXV (only one made in malasya inscription), perhaps if i take a picture i can try to match it with any vendor or post the pic here for you to see.

i only know that it is not welded, it has flare connections, 3/4 in 5/8 out, and the adjustment screw seems to be half way out.

best regards.

[Brian_UK]

In that case stick with your first estimate of the gas.

[nike123]

By compressor model it is R22

http://www.cc.una.ac.cr/catalog/cdet...cod2=3&fcod3=8

[frostedflake]

thanks for the link and the info

i'll keep you posted of how things go once i get the cold room running.

have a great friday the 13th lol