SWEP FI190

They cover the exchanger as a pressure component: PED for Europe, the UL listing for North America and KHK for Japan. They do not approve the system. On R32, R454B or R290 equipment the charge limits, ventilation and leak detection come from the equipment safety standard and local code, and the exchanger approval is one input to that.

Check two things against the listing. The stamped design pressure has to cover the high-side condition of the refrigerant in use. And if the project also calls for an ASME stamp or a CRN, name it when asking, since those are separate approvals with their own temperture envelopes.

Both use the same 524.50 x 202 mm plate and 460 x 136 mm port centres, so a tape measure will not separate them. The leading letters do: FI190 is the model that works as evaporator or condenser, while PI190 is a single-circuit evaporator.

If the letters are gone, identify the unit by its job in the circuit, then gather the plate count from the pack edge, the connection type and size on the refrigerant and water sides, the refrigerant, and the stamped pressure if legible. Send those with a photo of the label and we will confirm which model and build it is.

Physically they are twins: the same plate dimensions, the same 123.28 GPM water-side ceiling, and the same materials - 316 channel plates, 304 cover plates and copper braze. The difference is in what the plate is optimized to do.

The PI190 is a high-efficiency single-circuit evaporator for air- and water-cooled reversible chillers on low-GWP refrigerants, with AsyMatrix asymmetric plates. The FI190 is the model on this frame that serves as evaporator or condenser. Substituting one for the other because the footprint matches is the mistake to avoid: the machine will run, but at a different evaporating or condensing temperature than it was designed for. See the PI190 page for its figures.

NSC means 316 stainless channel plates, 304 stainless cover plates and copper braze. That suits R32, R454B and R290 against treated water or a glycol mix.

It does not suit ammonia, which attacks copper, or deionized water, which leaches it. Chloride-bearing water pits 316, so a heat pump on pool or brackish water needs that settled before selection. Refrigerant Compatibility lists the pairings.

It is right in new or redesigned equipment on R32, R454B or R290 in the 60 to 150 kW range, where one model has to serve as evaporator in one mode and condenser in the other, and where refrigerant charge is the constraint. The asymmetric channels, 0.149 dm3 on one side and 0.172 dm3 on the other, are part of how that charge is kept down.

It is the wrong choice for plain liquid-to-liquid duty, where the asymmetric pattern and integrated distribution are paid for and not used. It is also a poor like-for-like substitute in an older machine designed around a symmetric plate, since the water-side pressure drop and the refrigerant behavior both change.

No. The 28 m3/h (123.28 GPM) figure is the water-side ceiling set by the ports, and capacity is decided by the plate count and the temperatures. A unit can be well inside the flow ceiling and still be short of surface, or the reverse.

Watch the water-side pressure drop as the design flow approaches the ceiling, because port losses start to dominate and add nothing to heat transfer. If the duty needs more water flow than the 190 plate handles comfortably, or more surface than 140 plates gives, the answer is a larger frame, not a higher flow through this one. Note too that the 0.8 mm particle limit is tighter than on many frames, so the strainer has to match.

These models are catalogued alongside the FI190. Each has its own page with its dimensions, materials and part numbers.

SWEP PI190 - Single-circuit AsyMatrix evaporator for reversible chillers on low-GWP refrigerants, 60 to 150 kW.