Raypak Professional Series Installation & Operating Instructions Manual page 16

Fig. 7: For systems with pumps of 2 HP or greater (over 80 gpm), an external
bypass is required. Adjust the bypass valve to divert a minimum of 40
gpm through the heat pump pool heater. Connections are 2-inch unions. Plumb the
heat pump pool heater AFTER the filter and BEFORE any chlorinators.
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