372 ROUTE 4 BARRINGTON, NH 03825 USA TEL (603) 868-5720 FAX (603) 868-1040 E-Mail:sales@seafrost.com 1-800-435-6708 www.seafrost.com OPERATION & INSTALLATION INSTRUCTIONS SA-III Series C.F. HORTON & CO., INC. US ROUTE 4 BARRINGTON, NH 03825 U.S.A. (603) 868-5720 SEA FROST is a registered trade mark of C.F. Horton & Co., Inc. Aspects of the SEA FROST design are covered by US Patent # 4,356,708 Revised 10/91 Copyright 1991 by C.F. Horton & Co., Inc.
Table of CONTENTS SA-III OPERATION ICE MAKING MAINTENANCE HOW REFRIGERATION WORKS INSTALLATION SWAGELOK FITTINGS INSTALLATION INSTRUCTIONS VALVE CONTROL UNIT RECEIVER FILTER DRYER (RFD) THERMOSTAT & WIRING SAFETY GAUGES LEAK CHECKING NEW SYSTEM CHARGING CHECKING THE CHARGE / ADDING CHARGE TROUBLESHOOTING 2 2 3 4-5 6-7 8-9 10-12 13 14 14-15 15-16 17-18 18-19 19-21 21-24 24 25-27
SA-III OPERATION The SEA FROST SA-III system is an electrically driven refrigeration plant. Operation of the compressor will freeze the contents of the holdover devices in the boat's icebox providing refrigeration by cold holdover for an extended period after the compressor has been turned off. A boat without continuous power can benefit from this by operating the SEA FROST SA-III system when the generator plant is operated. Operation time will vary with each boat.
STORAGE OF ICE CUBES After ice has been made and harvested, store it in sealable plastic bags in the refrigerator or is so equipped in the freezer. Ice trays left in contact with the plate will melt rapidly if the plate goes above freezing. DEFROSTING It is important to defrost the holdover plate(s) regularly. This will maximize the efficiency of the system and ice making performance. It is not necessary to turn off the system to defrost. Scrape off any frost with a piece of wood or galley utensil.
WATER STRAINER The water pump is protected from damage and blockage by a sea water strainer. This strainer must be inspected and cleaned routinely. ROUTINE SERVICE AND INSPECTION We recommend sea strainer inspection before leaving the boat unattended dockside with the unit on. A visual inspection may be adequate depending on the type of strainer. To clean most types of strainers, close the seacock, open the strainer, remove the screen or basket, clean, reassemble and open the seacock.
LAY-UP (Winterizing) Flush the pump and condenser with plenty of fresh water. Pressure water should be flushed through the inlet side of the water pump. In freezing climates a 50/50 mix of antifreeze and water should be pumped through, after flushing, by operating the system for a very brief period. Connect a short hose to the suction side of the pump to draw from a bucket. Run the pump (switch on unit) until antifreeze is discharged.
heat, a condensing phase change is necessary. By increasing the pressure (compression) we can raise the boiling point of the gas vapor. Heat is removed from the pressurized gas vapor at the condenser. Sea water passing the condenser coils removes the heat, forcing the gas to a liquid state again. Pressure, therefore, is the key that allows passing the heat we have taken from the ice box to a warmer place (the sea water) and converting the gas to a liquid to be re-evaporated again.
TUBE HANDLING Installation is quite simple. All the copper tube comes to you with the ends capped. Nitrogen gas is added inside the tubes to displace air and moisture. Any routing of the tube must be done with the tube either taped or capped. Cap both tube ends after each cut. Work with only one line at a time, and only uncap one end at a time.
Step 3. Insert clean, smooth tubing with the pencil mark into the Swagelok tube fitting. You can be sure the tube is resting firmly on the shoulder of the fitting when the pencil mark is flush with the nut. Step 4. Tighten the Swagelok nut to a wrench snug* position. Scribe the nut with a pencil at the 6:00 o'clock position (see drawing, step # 2). * Wrench snug is the first point in the assembly tightening when the tube can not be pulled from the fitting, (i.e.
STEP 2 Before tightening the SWAGELOK nut, scribe the nut at six o’clock position. STEP 3 Now, while holding the fitting body steady with a backup wrench, tighten the nut 1 ¼ turns. Watch the scribe mark, make one complete revolution and continue to the 9 o’clock position. By scribing the nut at the 6 o’clock position as it appears to you there will be no doubt as to the starting position. When tightened 1 1 ¼ turns to the 9 o’clock position you can easily see that the fitting has been properly installed.
CONDENSING UNIT LOCATION AND MOUNTING The design of the SA-III allows placement of the unit in an enclosed space such as a cabin locker, sail locker or engine area. Service access and installation require that the front and left end (water fitting end) be accessible. Mount the Shore Assist level. The compressor is at the bottom. The unit may be bulkhead or platform mounted. Pilot holes have been pre-drilled for the aluminum angle clips. Use the #8 x 3/4" self tapping screws which are included.
WARNING: READ SAFETY SECTION BEFORE PROCEEDING The SA-III unit is shipped under some refrigerant pressure. Before removing the caps on the connection ports, remove the screw caps on the service valve covers and depress the cores with a fingernail to vent any existing pressure. After depressurizing, working with one line at a time, remove the Swagelok caps from compressor and condenser. Attach union fitting bodies. Make up 1/4 turn from wrench snug. This is a pre-Swaged connection...
RUNNING THE TUBING Connect 1/4" copper tube between the condensing unit and the planned location of the RFD. Continue with 1/4" to the expansion valve. Multiple plate hook-ups should be assemble as indicated by the specific diagram provided. A 3/8" line connects the valve unit to the compressor. If possible, run the 1/4" liquid line in contact with 3/8" suction line. This will be insulated in proper sequence.
A separate through hull fitting 3/4" or larger should be used. It should be as low in the boat as possible and away from head and cockpit drains. A forward facing scoop will prevent problems if the unit is operating underway. A large seawater strainer should be mounted above the seacock. The pump should be mounted horizontally. It should be higher than the strainer. The discharge should be on the top. (Refer to the drawing at the back of this manual.
THE CHARGE HOSE ENDS ARE DIFFERENT The charge hose supplied with the SEA FROST system has a metal insert in the fitting on one end. This fitting installs on the compressor suction service valve. VENTING THE CHARGE HOSE To avoid pulling air or other contaminants into the system, it is necessary to vent the air out of the hoses that are used to carry R-12 into the system. To vent the hose, open the can tap valve with the can upright (vapor) to allow a wind pressure to escape.
TO REMOVE THE GAUGES, turn off the compressor, wait for the pressure readings to equalize, then rapidly unscrew the hoses at the compressor. Re-cap the service ports. Keep gauges clean. Inspect rubber gaskets on hoses, leak-check gauge valve packing and all hose connections. Prior to use, any oil should be blown out of the hoses with refrigerant. The end of the hose that contains the depressor core is the end that attaches to the compressor service port. Check and reset "o" on low side, if necessary.
In cold weather, it is possible to raise the pressure in the system by warming the plate(s) with a light bulb left on in the cabinet until the plates are warm to the touch. There are two ways to leak-check a pressurized system: 1. Soap bubbles (a solution of dish soap and water works well). 2. Electronic leak detector (probe senses presence of halide refrigerant molecules). TO CHECK WITH BUBBLES Soap each connection and observe all sides of the connection with a strong light and a mirror.
When pressure shows "O" psi, connect the center hose to a high vacuum pump. Start the pump and slowly open gauge hand wheel. Evacuated to best vacuum. On a new system using a high vacuum pump this requires 15 to 25 minutes. When evacuation is finished close gauge hand wheel. Turn off the pump. Disconnect the center hose from pump and connect it to a can of refrigerant (See "Tapping a Can of Refrigerant"). Vent the hose from can tap to gauge body (See "Venting the Charge Hose").
READING THE SIGHT GLASS A clear sight glass signifies a sufficiently charged SEA FROST SA-III system when the compressor is operating. To determine the meaning of "clear", notice the appearance of the RFD sight glass when the system is at rest with the compressor off. This is a "clear" glass. SPECIAL WARNING: A clear sight glass can also indicate a completely EMPTY system.
PROPER CHARGE AMOUNT MAXIMUM CHARGE can be computed by multiplying liquid line length (distance in feet of tubing from bottom of condenser to Valve/Control Unit) by 1/3 ounce of R-12, and then adding 10 ounces. (Shaking the can is a good method of determining the amount of refrigerant remaining in the can). DO NOT EXCEED THIS AMOUNT. GENERAL INFORMATION OPERATING PRESSURES will vary with water temperature, and water flow. Generally, HIGH SIDE will peak with warm plate(s) in two minutes.
CHECKING THE REFRIGERANT CHARGE ~ ADDING CHARGE Checking the refrigerant charge must be incorporated into a routine maintenance schedule. MONITOR THE SIGHT GLASS CONTINUALLY. See, READING THE SIGHT GLASS." If the sight glass does not show the presence of refrigerant within a minute of operation the system is empty. TURN OFF SYSTEM, and follow the procedure in "TROUBLE SHOOTING" below. If the white foam is evident watch closely for the transition to "clear" (see "READING THE SIGHT GLASS".
TROUBLESHOOTING The most common problems that can occur in a SEA FROST SA-III system are: 1. Loss of refrigerant charge resulting from leaks. 2. Moisture or dirt plugging the valve. 3. Compressor malfunction due to loss of refrigerant charge. 4. Overcharge, disconnect of the high-pressure switch. 5. Cooling water flow loss causing the high-pressure switch to disconnect. STEP 1. Gather information as to the nature of the problem before operating the system.
For further troubleshooting, attach purged gauges to compressor service ports or observe the temperature of lines as follows. a) If the ice box and SEA FROST Block or plates are warm and pressure readings are below 50 psi with compressor off (in 50 degree F or higher ambient conditions), pressurize system with R-12 and leak-check (see "LEAK CHECKING"). b) If the pressure reading is over 50 psi with compressor off, operate the system and proceed to check charge level via sight glass and charge if needed.
Remove the RFD. If there is to be a delay in reinstalling an RFD, tape or cap the open connectors to make sure no air or dirt enters the system. Replace only with identical unit: SEA FROST RFD is a drier and a receiver/filter. SEA FROST RFD’s are oil compensated to cover oil removed in the old part. Install a new RFD, observing proper INLET ("IN") position. (The sight glass window is offset toward the output) Refrigerant flow is from the condenser to the "IN" side. The out side is to the V/CU.
372 ROUTE 4 BARRINGTON, NH 03825 USA TEL (603) 868-5720 FAX (603) 868-1040 E-Mail:sales@seafrost.com 1-800-435-6708 www.seafrost.com THERMOSTAT CALIBRATION INSTRUCTIONS Note: Be sure that the unit is operating properly before making any thermostat adjustments. The sensing bulb must be in excellent thermal contact with the plate or block. The range of this control may be changed. To access the adjustment screw, remove the four mounting screws on the thermostat panel.
HOLDOVER PLATES STAINLESS STEEL EVAPORATOR PLATES 26
WATER CIRCUIT 27
SA3 SCHEMATIC 28
