4.3 Connecting Seawater to Heat Exchanger

Connecting Seawater to Heat Exchanger

Refer to Figure 4 for typical seawater plumbing arrangement.

Figure 4 – Typical Seawater Plumbing Arrangement

  1. Connect seawater pump to Seakeeper dedicated through-hull fitting. A strainer and seacock valve should generally be installed between the seawater inlet and the pump.
  2. Connect seawater from installer-supplied pump to lower ¾ in. (19 mm) hose barb on heat exchanger. Use the same practices as other below waterline seawater plumbing. Required flow rate is 2.5 GPM (9.5 LPM) minimum and 8 GPM (30.3 LPM) maximum.
  1. Connect seawater discharge (upper hose barb) to overboard drain. Use the same practices as other below waterline seawater plumbing.
  2. In addition to initial operation at dock, new installations should be checked for minimum 2.5 GPM (9.5 LPM) flow while vessel is at speed and when backing down.
    • If no other method of confirming flow is available, discharge line may be temporarily diverted to a bucket. Flow is calculated from time to fill a known volume.
    • A self-priming seawater pump (customer/installer supplied) may be required due to installation location to maintain water flow in all underway conditions where cavitation may occur and potentially cause an air-lock condition restricting seawater flow to the heat exchanger.
  3. Inspect raw water plumbing after sea trial for any signs of leakage.
  4. Heat exchanger contains removable end-caps to provide access for cleaning the tube bundle.

Seakeeper Optional DC Seawater Pump (P/N 30331)

  1. Seakeeper offers a self-priming DC Seawater pump as an optional addition, P/N 30331– DC Seawater Pump Assembly, shown in Figure 6.
  2. The Seakeeper Seawater Pump is a 24 VDC pump operated at 12 VDC for the Seakeeper 6.
  3. The pump assembly is pre-wired for connection to Seakeeper 6 Cable 5 and includes a seawater strainer and various fittings. The pump specifications are as follows:

NOTE: Use only SeaFlo-provided threaded fittings for DC Seawater Pump 30331.

Volts24 VDC (operate at 12 V for Seakeeper 6)
Rated Flow2.5 – 8 GPM (9.5 – 30.3 LPM)
Overcurrent Protection Rating15 A
Ignition ProtectionISO 8846 or equivalent
Figure 6Seakeeper 6 DC Seawater Pump (P/N 30331)