SWEP E8AS

Mount it upright with the long 315 mm dimension vertical, and pipe the heating water and tap water in counter-current - one entering at the top, the other at the bottom. Counter-current gives the closest approach; piped co-current, the same unit will leave the tap water noticeably cooler.

Because the channels are asymmetric, each circuit also has to stay on its own side. Mark the pipes before the old unit comes off.

Support the pipework so the four threaded connections carry no load, and hold the fitting with a second wrench when tightening. A connection that is used as a pipe hanger eventually cracks at the braze.

If the model and plate count match, yes. The face is 315 x 74 mm and the port centres are 278 x 40 mm, and those do not change with plate count.

Depth is the dimension that moves. Catalogued E8AS builds run from 10 to 42 plates, with 46 the published maximum, and each plate adds to the pack thickness, so a unit with more plates than the original may foul a bracket or casing panel.

Check the port centres with care: siblings on this frame differ from the E8AS by only a millimetre or three on the face, which is too little to see by eye.

Yes, wherever it can see freezing air or a circuit that drops below freezing. The channels hold very little water, so they freeze quickly, and ice in a brazed pack splits plates or braze joints. The first sign is usually a leak between circuits after the thaw.

On tap water duty the potable side cannot take glycol, so protection comes from where the unit sits, keeping it warm, or draining it down for the season. Where the heating side runs a glycol mix, tell us the type and concentration: glycol is thicker than water and transfers heat less well, which can change the plate count. See Freeze Protection.

The full designation from the nameplate, for example E8ASHx20/1P-SC-S 4x3/4"(20). That one line gives the model, plate type, plate count, pass arrangement, material, pressure class and connections.

If the label is unreadable, send the face dimensions, the port centre distances, the number of plate edges counted along the side, and the connection thread size, with a photo. The equipment make and model the exchanger came out of also helps.

For a new duty rather than a replacement, we need both flows, all four temperatures and the allowable pressure drops. You can send any of this through Request a Quote.

It suits ordinary tap water, closed heating water and glycol mixes - the combination of 316/316L plates and copper braze is the general-duty construction, coded SC, and it is what every E8AS on file uses.

It is the wrong construction for ammonia, which attacks copper, and for deionized or ultrapure water, which leaches copper out of the braze. Chloride-bearing water - pool water, brackish or heavily chlorinated water - is a plate problem rather than a braze problem: 316 pits under chlorides. Copper braze also sets a temperture ceiling of roughly 185 C, well above tap water duty. If the fluid is anything other than clean water or glycol, state it on the inquiry.

It is the pressure class, which is a category rather than a rating. Class S covers 31 bar at 155 C and is the general-purpose class; all eleven E8AS part numbers on file are class S.

The rating of a specific unit is the design pressure and temperature stamped on its own nameplate, and that is the number to compare with the system relief setting. A replacement should carry the same class letter as the original, so the new unit is the same build as the one the equipment was designed around.

These models are catalogued alongside the E8AS. Each has its own page with its dimensions, materials and part numbers.

SWEP B8T - Nickel-brazed - the copper-free option at small size, for ammonia and aggressive media.

SWEP B8DW - The most compact double-wall brazed plate heat exchanger in the SWEP range.

SWEP B8LAS - Compact AsyMatrix brazed plate heat exchanger pairing high thermal performance with low pressure drop.

SWEP BX8T - Compact All-Active brazed plate unit for heat pumps and container refrigeration, to 17.61 GPM.

SWEP E8LAS - AsyMatrix brazed plate heat exchanger on the B8T frame for the highest thermal demands in tap water.

SWEP E8T - A compact copper-brazed plate heat exchanger for wall-hung, non-condensing boilers.