System design

[coolerboy]

so having some time on hand and my mind working in overdrive as always, i had the brilliant idea of building my own unit, would be a reefer unit for a rigid box......

BUT... only being in the trade for about 4 years now, i havent the slightest idea of where to start

does anyone know where i can find info on unit design? also any advice would help as usual and credit will be given where its due.

ciao

[The MG Pony]

Well start with the box, how big, how well insulated, figure out how much heat gain it will have. Figure out the product that will go in it and how much and at what temp you need to keep it at and at what humidity!

From there size the evap and expansion valve, then from that size the condencing plant.

[coolerboy]

Thats the problem as the application of the unit will vary.... Box sizes and insulation will vary from 38 cubic metres to 63 cubic metres with 50 mm to 100mm polyurethane or styrofoam walls. Same goes for the product, anything from +20 to - 25 degrees celsius.

The heat penetration and humidity will also be a non constant as our weather and all that also varies a lot from one region to the next.

ciao

[coolerboy]

It would also have to be a self contained unit with electric standby.

The best way i figured it was to strap a generator on the back of small 3 cyl engine and use it to power a compressor (like the copeland) fans and all that. would also like to use manuli type hoses, less copper = less pipes prone to break.

[taz24]

It would also have to be a self contained unit with electric standby.

The best way i figured it was to strap a generator on the back of small 3 cyl engine and use it to power a compressor (like the copeland) fans and all that. would also like to use manuli type hoses, less copper = less pipes prone to break.

Why not just use a second hand refrigerated container? Lot less hassle and the work is done for you.

taz.

[frank]

Thats the problem as the application of the unit will vary.... Box sizes and insulation will vary from 38 cubic metres to 63 cubic metres with 50 mm to 100mm polyurethane or styrofoam walls. Same goes for the product, anything from +20 to - 25 degrees celsius.

The heat penetration and humidity will also be a non constant as our weather and all that also varies a lot from one region to the next.

ciao

As with any design, it should be for the worst case, so you should design for 63m3 with 100 polyurethane or styrofoam walls at +20C and the worst ambient conditions.

Without any other specific data you are just guessing.