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Just wondering. On this BPX 410-050 (BG) there are 2 in and 2 out. The manual calls for , boiler side F1 in, and F4 out. DHW side, F3 in and F2 out. This particular htex is piped opposite. As in; the outs and ins are correct but the boiler side is on the F2, F3 ports.
Anyone know if that makes a performance difference?