design

[freezy]

Hi all,

I have been asked to connect a Trane RAUL 190(cooling only) to a Trane AHU on a roof with about 6 metres of pipework.
I cannot find full installation information but I know the condenser has 1"5/8, 7/8" connections and the units are matched on R407C with a 55 Kw capacity.

My concerns are these,

I'm not sure if I should run the pipe in the afore mentioned sizes.

I will need to install a drier and sight glass in the liquid line, do I also need a suction drier.

What expansion valve will I need and what orifice.

Approximatley how much R407C should I estimate to use.

I dont normally have to design, any help would be appreciated.

[dogma]

holy moley...........................................

[freezy]

dogma,

explain

[Brian_UK]

Freezy, have at look at the Trane manual for the RUAL unit, it provides performance data for the gas you want to use... see here...
http://www.trane.com.au/equipmentdocs/RAUL.pdf
hope this helps.

[Peter_1]

It never harms to install a suction line filter dryer.
The first core is made of some woven fabric, replaced after some running hours by a fine mesh filter.

Make sure the copper lines are installed the right way.

1 5/8 suction and 7/8 liquid.

[freezy]

Thanks peter,

I am unsure about the 7/8" liquid line, it seems quite large for a 55 Kw evaporater. Does this mean my expansion valve should have a 7/8" inlet connection as this would probably be a power assembley valve, I cannot find a TEV with connections above 5/8". danfoss TX2's, etc have capacities opto about 150 Kw but they have 3/8" connections.

[Peter_1]

Thanks peter,

I am unsure about the 7/8" liquid line, it seems quite large for a 55 Kw evaporater. Does this mean my expansion valve should have a 7/8" inlet connection as this would probably be a power assembley valve, I cannot find a TEV with connections above 5/8". danfoss TX2's, etc have capacities opto about 150 Kw but they have 3/8" connections.

A TX2 for 150 kW? Impossible. Something around 25 kW maxi should be better but 150 kW???Perhaps without an orifice in it

7/8 is correct, it depends of course also on the allowable pressuredrop and speed in the lines. I take usually 10 m/s.

You may try it with a smaller 3/8 or 1/2, it's your installation.

You will need a TE5 with an orifice 04, just looked in the manual.

But, I'm also a little afraid that you don't quite understand the basics. Is your boss not able to select these items and the lines? If he isn't, then he better should go back some time to school again.