4.0 Cooling Installation

4.1 Cooling Installation Introduction

Reference Documents & Drawings:

90257 – Seakeeper 9 Cable Block Diagram

90251 – Seakeeper 9 Cooling Water Schematic

30331 – Seakeeper DC Seawater Pump Assembly

TB-90191 – Seawater Cooling Pump Recommendations

The Seakeeper 9 is shipped with the cooling circuit filled and ready for use (See Figure 29). The Seakeeper 9 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 9 heat exchanger is between 4 – 8 GPM (15.1 – 30.3 LPM), under all vessel operating conditions. Prior to operation, confirmation of glycol level is required.

Seakeeper offers a compatible self-priming DC Seawater Pump (P/N 30331) that is pre-wired for the Seakeeper 9 installation and covered under the standard Seakeeper Warranty. See Drawing No. 30331, Seaflo Seawater Pump Assembly for details and the Seakeeper Options and Accessories Price List for pricing information.

4.2 Cooling System Considerations

1. Installer is responsible for supplying a dedicated seawater pump and associated plumbing. Seawater connections on the Seakeeper heat exchanger mate with ¾ in. (19 mm) hose. An optional seawater pump can be purchased through Seakeeper, P/N30331.
2. The seawater pump is powered by Cable 5, via “SW Pump 24 VDC Out” on the Seakeeper 9, as outlined in Electrical Installation Section.
   
   • This pump must operate on 24 VDC, 10 A OR 12 VDC, 15 A power. Pumps requiring other voltages or higher current can still be controlled by using this supply to trigger an installer-supplied relay but a separate source of power must be provided.
3. A dedicated through-hull fitting should be installed for each Seakeeper unit onboard the vessel to ensure sufficient seawater flow to each unit.
4. It is recommended that the seawater pump is located below the waterline, as close to the baseline of the vessel as practically possible, to maintain positive inlet pressure on the pump in all operating conditions.
5. 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.
6. Vented loops are optional and should only be considered with centrifugal style pumps. Self-priming or positive displacement style pumps do not require a vented loop, this includes Seakeeper P/N 30331.
7. Maximum seawater pressure in heat exchanger is 20 psi (1.4 bar)
8. Seawater flow requirement through heat exchanger is 4 GPM (15.1 LPM) minimum and 8 GPM (30.3 LPM) maximum under all operating conditions of the boat. When sizing seawater pump, installer should factor in losses for raw water plumbing. In addition to initial operation at dock, new Seakeeper installations should be checked to be within the flow requirements while vessel is at speed. Flows higher than 8 GPM (30.3 LPM) could affect heat exchanger life.

4.3 Connecting Seawater to Heat Exchanger

Refer to Figure 31 for typical Seakeeper 9 seawater plumbing arrangement.

1. Connect seawater from installer-supplied pump to lower ¾ in. (19 mm) hose barb on heat exchanger. (See Figure 1) Use the same practices as other below waterline seawater plumbing. Required flow rate is 4 GPM (16 LPM) minimum and 8 GPM (30.3 LPM) maximum.
2. Connect seawater discharge (upper hose barb) to overboard drain. (See Figure 29) Use the same practices as other below waterline seawater plumbing.
3. In addition to initial operation at dock, new installations should be checked for minimum 4 GPM (16 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 near the intake may occur and potentially cause an air-lock condition restricting seawater flow to the heat exchanger.
4. Inspect raw water plumbing after sea trial for any signs of leakage.
5. Heat exchanger contains removable endcaps 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 operated at 24 VDC for the Seakeeper 9 (Figure 32).
2. The pump assembly is pre-wired for connection to Seakeeper 9 Seawater Pump Output Cable, “SW Pump Output” and includes a seawater strainer and various fittings. The pump specifications are as follows:

NOTE: Only use SeaFlo-provided threaded fittings with 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 reservoir and clear tube between heat exchanger and reservoir should be filled with green coolant mixture, as shown in Figure 33. If level has dropped, check for evidence of leaks at all connections before adding fluid as described below. If coolant is at the correct level, skip to Section: Connecting Seawater to Heat Exchanger.
2. Note: Some amount of entrained air in the fluid is normal and acceptable.  This air will be evident by some cloudiness of the fluid.  As long as the fluid remains at the specified fill level during operation, the remaining cloudiness is not an issue.

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. Remove vent cap on top of reservoir. Pour mixture in until level reaches 2/3 reservoir as shown in Figure 33. Filling reservoir above this level will not cause any damage but coolant may be expelled from vent on top of cap due to normal thermal expansion of coolant.
4. Connect 24 V to controller.
   1. At the MFD app / optional 5″ Touch 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 down inside reservoir and check that coolant level is above upper port on reservoir as shown in Figure 4. Replace cap.
   5. After several minutes of running, press POWER ON/OFF button to turn power off to the flywheel.
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 glycol level after sea trial and add fluid if required.