SWEP B57

Undersized, the evaporating temperature drops to make up for missing surface. The compressors lose capacity and efficiency, and the water side runs closer to freezing than the design intended.

Oversized is the less obvious problem on a dual-circuit unit. With one compressor off, the running circuit sees a plate pack built for both, and refrigerant velocity can fall far enough that oil stops returning and the superheat signal becomes unstable. Size a B57 against the part-load condition as well as full load, and give both circuit capacities when asking for a selection.

Vertically, with the 693 mm dimension upright. Two-phase duty depends on gravity to distribute liquid evenly across the channels, and a unit laid on its side or back feeds some channels and starves others.

Pipe the water counter-current to the refrigerant for the closest approach, and keep the two refrigerant circuits identified from the nameplate port order - crossing them on a D-arrangement unit is an easy error that only shows up at commissioning. Support every line independently. The connections are brazed to the cover plate and are not there to hold up pipe, a filter-drier or a vibrating discharge line. See Mounting and Piping.

Yes. The published limit is 1 mm, and a brazed pack cannot be opened to pull out what gets past. A partly blocked evaporator is also a freeze risk: the blocked channels stop flowing, the refrigerant keeps cooling them, and the standing water freezes and splits the plates.

Fit the strainer upstream of the water inlet with isolation valves and a pressure gauge on each side, and clean it after the first days of running on any new or modified pipework, when weld slag and pipe scale come loose.

Use the published formula: 17.51 kg plus 0.567 kg per plate (38.59 lb plus 1.250 lb per plate). At the 220-plate maximum that is about 142 kg (314 lb) dry. The water and refrigerant it holds come on top, with 0.335 dm3 in each channel.

That is a floor-mounted unit. Set it on a base frame or feet under the pack, with a strap or bracket to stop it tipping, and bring it in with a hoist or a lift table. Lifting by the connections bends the cover plate.