Liquid line increase

[bernard]

Hi

While looking at large cold room with 3 blowers supplied from 3 carrier condensing units,I noticed the liquid lines went from 5/8 to 7/8 about .5 meter after sight glass.Is this ok.


Regards Bernard

[slingblade]

I dont see any reason why not. a system with an excessively long pipe run could have the tubing oversized to compensate for any pressure drop involved.

[US Iceman]

Hi Bernard,

I doubt the difference in sizes will present any problems. When I did a lot of supermarket work I routinely over sized the liquid lines, and insulated them in areas where the piping ran through a warm space.

The larger piping allows a lower pressure loss in the liquid line. That helps a lot. Secondly, if the liquid line runs through a space with an air temperature lower than the liquid line temperature, that also helps.

If the liquid line runs through a warm space, the liquid line can absorb heat, which does not help you. In fact, it can decrease the system capacity.

[bernard]

Hi

Yes the pipe runs are long so thats the reason,another question the condensers were large but the recievers small.You would never be able to pump them down.Sorry I don,t have much info on the system and they were running fine.But should the receivers not be sized to cope with the liquid in the system.


Thanks Bernard

[US Iceman]

But should the receivers not be sized to cope with the liquid in the system.

Well, I suppose if you ever wanted to have a chance of pumping the entire system down (the parts connected to that receiver) the receiver would need to have sufficient volume (system charge + approx. 25%) to accommodate the pump down.

I would question why the receiver is so small, unless it was intended for a close coupled system.