4.0 Cooling Installation

4.1 Cooling Installation Introduction

The Seakeeper 6 is shipped with the cooling circuit filled and ready for use. Only a quick confirmation of glycol level is required.

Reference Documents & Drawings:

• 30331 – Seakeeper DC Seawater Pump Assembly
• 90396 – Seakeeper 6 Cable Block Diagram
• 90397 – Seakeeper 6 Cooling Water Schematic
• TB-90191 – Seawater Cooling Pump Recommendations
• TB-90947 – Seawater Plumbing Best Practices

The Seakeeper 6 is shipped with the glycol cooling circuit filled and ready for use. The Seakeeper 6 requires connection to a raw water pump, referred to as the seawater pump, to cool the closed loop cooling circuit on the unit.  The required seawater flow through the Seakeeper 6 heat exchanger is between 2.5 – 5 GPM (9.5 – 18.9 LPM) when the on-demand cooling system requires cooling. Prior to operation, confirmation of glycol level is recommended.

Seakeeper offers a compatible self-priming DC Seawater Pump (P/N 30331) prewired for the Seakeeper 6 Installation and covered under the standard Seakeeper warranty. The pump conforms to the seawater plumbing best practices noted in TB-90947. Refer to Drawing No. 30331, SeaFlo^® Seawater Pump Assembly, and the Seakeeper Options and Accessories Price List for details.

4.2 Installation Considerations

1. The installer is responsible for supplying a dedicated seawater pump, an electric isolation valve, and associated plumbing. Seawater connections on the heat exchanger mate with ¾ in. (19 mm) hose. An optional seawater pump can be purchased from Seakeeper (P/N 30331).
2. Unintended seawater flow from the seawater pick-up during underway operations is unacceptable and may cause stress on internal components. Unintended flow should be mitigated through an inlet electric ball valve. Continuous cooling flow from shared through-hull plumbing, a centralized chiller, or a cooling system is unacceptable for Seakeeper models.
3. There is no need to disconnect the hose from the glycol pump except to replace the pump. In this case, provision will need to be made to catch the draining glycol, as the plumbing is disconnected. Use caution to avoid breaking plastic hose connections on the pump casing.
4. The seawater pump is powered by the DC Seawater Pump Output cable on the Seakeeper 6, as outlined in the Electrical Installation Section 3.2.
   
   • This pump must operate on 12 VDC, 10 A OR 24 VDC, 10 A power. Pumps requiring other voltages or higher current can still be controlled by using this supply to trigger an installer-supplied contactor, but a separate power source must be provided.
5. Install electric ball valve (P/N 20762) and two 1 in. to 3/4 in. fittings of Kit 90970 (Fig. 44) in the suction line of the pump between the strainer and the seacock valve and within 40 in. (1 m) of the seawater pump.

6. A dedicated through-hull fitting should be installed for each Seakeeper unit onboard the vessel to ensure sufficient seawater flow to each unit.

7. It is recommended that the seawater pump be located below the waterline, as close to the vessel’s baseline as practically possible, to maintain positive inlet pressure on the pump in all operating conditions.
8. A self-priming seawater pump is recommended to maintain water flow in all underway conditions. Cavitation can occur at the seawater inlet and potentially cause an air-lock condition restricting seawater flow to the heat exchanger.
9. Vented loops are optional and should be considered only with centrifugal-style pumps. Self-priming or positive displacement style pumps do not require a vented loop; this includes Seakeeper P/N 30331.
10. Maximum seawater pressure in the heat exchanger is 20 psi (1.4 bar)
11. Seawater flow requirement through the heat exchanger is 2.5 GPM (9.5 LPM) minimum and 5 GPM (19 LPM) maximum under all operating conditions of the boat. When sizing the seawater pump, the installer should account for losses in the raw water plumbing. In addition to initial operation at the dock, new Seakeeper installations should be checked to ensure they meet flow requirements while the vessel is at speed. Flows above 5 GPM (19 LPM) could shorten heat exchanger life.

4.3 Connecting Seawater to Heat Exchanger

Connecting Seawater to Heat Exchanger

Refer to Figure 45 for typical seawater plumbing arrangement.

1. Connect the seawater pump to the Seakeeper dedicated through-hull fitting. A seacock valve, an electric ball valve, and a strainer should be installed between the seawater inlet and the pump (See Figure 45).
2. Connect seawater from the installer-supplied pump to the lower ¾ in. (19 mm) hose barb on the heat exchanger. Use the same practices as other below-waterline seawater plumbing. Required flow rate is 2.5 GPM (9.5 LPM) minimum and 5 GPM (18.9 LPM) maximum.

3. Connect the seawater discharge (upper hose barb) to the overboard drain. It is recommended to install a visible flow meter in the discharge line, though it is not required for permanent installation. Use the same practices as other below-waterline seawater plumbing.
4. In addition to initial operation at the dock, new installations should be checked for seawater flow while the vessel is at speed and when backing down. The flows should be recorded when the seawater pump is running and when it is off.
   
   • If no other method of confirming flow is available, the discharge line may be temporarily diverted to a bucket. Flow is calculated from the time required to fill a known volume (e.g., a 5-gal. bucket).
   • A self-priming seawater pump (customer/installer supplied) may be required at the installation location to maintain water flow in all underway conditions where cavitation may occur and potentially cause an air lock, restricting seawater flow to the heat exchanger.
5. Inspect raw water plumbing after sea trial for any signs of leakage.
6. The heat exchanger has 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 46.
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 “DC Seawater Pump Out” cable 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.

4.4 Adding Coolant

1. Cooling system is filled to proper level when shipped, with a mixture of 50% ethylene glycol and 50% distilled water. The clear tube between heat exchanger and reservoir should be filled with green coolant mixture. If level has dropped, check for evidence of leaks at all connections before adding fluid as described below.

2. Mix 50% ethylene glycol with 50% distilled water in a clean container. Refer to Table 1 or glycol manufacturer’s literature for freezing points.

3. Pour mixture in until level reaches top of reservoir as shown in Figure 47. Filling reservoir above this level will not cause any damage but coolant may be expelled from pressure relief port in cap due to normal thermal expansion of coolant.
4. Connect 12 V to controller.
   1. At the MFD app or Display check for any ALARMS
      
      
   2. Press the POWER ON/OFF button.
   3. The flywheel will start to spin and the glycol pump will start.
   4. Recheck glycol level with fluid circulating in coolant circuit. Sight reservoir and check that coolant level is above upper port on reservoir as shown in Figure 47.
   5. After several minutes of running, press POWER ON/OFF button to turn power off to the flywheel and glycol pump. The glycol pump will stop and the flywheel will coast to a stop.
5. The cooling system is self-purging. If small amounts of air are in the system, they will most likely be dislodged during the first sea trial. Re-check level after sea trial and add fluid if required.