4.0 Cooling Installation

4.1 Cooling Installation Introduction

Reference Drawings and Documents:

• 90511 – Seakeeper 1 Cable Block Diagram
• 90512 – Seakeeper 1 Cooling Water Schematic
• TB 90191 – Seawater Cooling Pump Recommendations
• 30331 – Seakeeper DC Seawater Pump Assembly

The Seakeeper 1 is shipped with the cooling circuit filled and ready for use. To cool the closed-loop cooling circuit on the unit, it requires a connection to a raw water pump, referred to as the seawater pump. Under all vessel operating conditions, the required seawater flow through the Seakeeper 1 heat exchanger is between 2 and 4 GPM (7.6 and 15.2 LPM). Prior to operation, confirmation of the glycol level is required.

Seakeeper offers a compatible self-priming DC Seawater Pump (P/N 30331) prewired for the Seakeeper 1 Installation and covered under the standard Seakeeper warranty. For details, see Drawing No. 30331—Seakeeper DC Seawater Pump Assembly and the Seakeeper Options and Accessories Price List.

4.2 Installation Considerations

1. The installer is responsible for supplying a dedicated seawater pump and associated plumbing. An optional seawater pump can be purchased through Seakeeper, P/N 30331.
2. Seawater connections on the Seakeeper heat exchanger mate with ½ in. (13 mm) hose.
3. As outlined in the Electrical Installation section, the seawater pump is powered by a cable (P/N 20334) via “SW Pump 12 VDC Out” on the Seakeeper 1.
   
   1. The seawater pump operates on 12 VDC with a max overcurrent protection rating of 15 A.
4. To ensure sufficient seawater flow to each Seakeeper unit onboard the vessel, a dedicated through-hull fitting should be installed.
5. It is recommended that the seawater pump is 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.
   
   1. A self-priming seawater pump may be required 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. Maximum allowable seawater pressure in heat exchanger is 20 psi (1.4 bar).
7. The seawater flow requirement through the Seakeeper heat exchanger is 2 GPM (7.6 LPM) minimum and 4 GPM (15.1 LPM) maximum under all operating conditions.
   
   1. When sizing the seawater pump, installers should consider losses for raw water plumbing.
   2. A forward-facing scoop / highspeed seawater inlet should be installed to ensure sufficient seawater flow during underway operation.

4.3 Connecting Seawater to Heat Exchanger

Refer to Figure 2 for 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 the installer-supplied seawater pump to the lower ½ in. (13 mm) hose barb on the heat exchanger.
   
   1. Use the same practices as other below waterline seawater plumbing.
3. Connect the seawater discharge (upper hose barb) to the overboard drain. Use the same practices as for other below-waterline seawater plumbing.
4. During commissioning, seawater flow should be checked to be within the flow requirements while the vessel is at rest, at speed, and when backing down.
   
   1. If no other method of confirming flow is available, the discharge line may be temporarily diverted to a bucket. The flow rate is calculated based on the time required to fill a known volume in GPM or LPM.
   2. Flowrates over 4 GPM (15.2 LPM) could affect heat exchanger life.
5. After sea trial / commissioning, inspect all raw water plumbing for any signs of leakage.

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 below.
2. The Seakeeper Seawater Pump is a 24 VDC pump operated at 12 VDC for the Seakeeper 1 and maintains a seawater flow of approx. 2.5 GPM (9.5 LPM) at 12V DC.
3. The pump assembly is pre-wired for connection to Seakeeper 1 Seawater Pump Output Cable and includes a seawater strainer and various fittings. The pump specifications are as follows:

4.4 Adding Coolant

1. The Seakeeper 1 cooling system is filled to proper level when shipped, with a mixture of 50% ethylene glycol and 50% distilled water.
2. The coolant reservoir should be filled with colored coolant mixture, as shown in the following figure. If level has dropped, check for evidence of leaks at all connections before adding fluid as described below.
3. If coolant is at the correct level, (see Figure 2) skip to the Connecting Seawater to Heat Exchanger section.

4. Mix 50% ethylene glycol with 50% distilled water in a clean container. Refer to glycol manufacturer’s literature for freezing points.
5. Ethylene glycol with corrosion inhibitors is required. Most commercially available glycol has these additives standard.
6. Remove reservoir cap and pour mixture in until level reaches top face of the reservoir enclosure, as shown in Figure 4.
   
   1. Filling reservoir above this level will not cause any damage but coolant may be expelled from the vented cap due to normal thermal expansion of coolant.
7. Once the Seakeeper 1 and DC Seawater pump are connected to 12 VDC power:
   
   1. Check the Seakeeper Display interface for any ALARMS.
   2. Cycle the Seakeeper 1, press the POWER ON button.
   3. The flywheel will start to spin and the glycol pump will start.
   4. Recheck glycol level with fluid circulating in coolant circuit to ensure the correct fill level is maintained.
   5. After several minutes of running, press POWER OFF button.
8. The cooling system is self-purging. If small amounts of air are in the system, they should be dislodged during the first sea trial. Recheck level after sea trial and add fluid if required.

NOTE: It is not uncommon to see some air in the coolant system.
It is normal and will not affect operation.