SWEP B220

B220 is the frame. H is the plate: the obtuse chevron, with high heat transfer and high pressure drop. x133 is the plate count. /2P means two passes. SC is 316/316L plate with copper braze. M is the pressure class, up to 45 bar at 135 C and fatigue tested.

The connections follow in port order. This unit reads 2x1 1/2 in / 2x1 1/2 in, written as two pairs because a two-pass pack has ports on both cover plates. The single-pass builds on file read 4x2 in instead.

From the count alone, the published weight formula puts this unit at about 53 kg (117 lb) dry.

The plate letter and the plate count. This frame is built with H, L and M plates, and nothing measurable from outside tells them apart, yet they select very differently. If the letter after B220 is gone, send the duty the unit runs so the plate can be confirmed by selection.

Do not round the count. Our catalogued builds run from 60 to 220 plates and include odd numbers such as 133, so 'about 130' is not a match. Count the plate edges if the stamping is worn.

A D in the pass field marks a dual-circuit build.

Yes, in place, by circulating a cleaner through the water side in reverse and flushing afterward. The refrigerant circuits are not cleaned.

This frame needs it sooner than most if the water is poor. It has small channels, 0.14 dm3 each, and a published particle limit of 0.7 mm. Fit a strainer finer than 0.7 mm and track water-side pressure drop from the day of commissioning, so there is a clean baseline to compare against.

Clean when the pressure drop starts to rise, not after channels have blocked.

A single-pass unit sends each fluid through all of its channels once, with all four connections on the front cover. A two-pass unit sends it through half the channels and then back through the other half. That doubles the thermal length for a closer approach, at the cost of a much higher pressure drop, and it puts connections on the rear cover as well.

The piping consequence gets overlooked. A two-pass pack has pipework at both ends, so it cannot be swapped for a single-pass unit without re-piping, and its rear connections move if the plate count changes. Match the pass arrangement on the nameplate. Approach temperature and pressure drop explain the trade.

Check three things beyond the 524 x 202 mm face: port centres, pack depth and connection type. Port centres of 442 x 120 mm are fixed for the frame, so existing pipe drops line up on any single-pass B220.

Depth is the variable. The pack gets deeper with every plate, and the front connections stay where they are while the pack grows toward the back. If the replacement has more plates than the original, measure the clearance behind the unit and check the bracket or strap length.

Weight moves with it: about 30 kg at 60 plates and 81 kg at 220. Then confirm the connection type, since this frame is catalogued threaded, Victaulic, solder and flanged.

The frame is published with PED, UL and KHK approvals, and UL is the one a North American refrigeration inspector normally looks for. The M-class build is the one intended for refrigerants such as R410A.

Read the stamped figures, though, not the class letter. M is a category, up to 45 bar at 135 C, and the relief device and high-pressure cutout are set against the design pressure stamped on the actual unit.

For Canadian installations a CRN registration is usually required in addition, and its envelope runs from -196 C to +225 C. Note the province on the quote request.