G'day all.

When we do an install of a new walk in freezer we always make it a pump down system with an oil trap if condensing unit is higher than evaporator.

Having said this I was reading some information supplied by manufacturers of evaporators that are very popular in Australia, which read as follows.

Do not make the system a pump down system as the defrost requires refrigerant to be in the coil to distribute the heat evenly throughout the coil and allow an adequate defrost. Suction line must exit the evaporator and go straight up to prevent refrigerant draining on a defrost cycle, causing poor defrost.

Just interested on other members opinions on this.
Thanks in advance.