Model 30IM Service Manual Contents 1. Introduction Page 1.1 Product Specifications 2 1.2 Serial Nameplate 3 1.3 Before Servicing 3 1.4 After Servicing 4 1.5 Basic Refrigeration Tools 4 1.6 Installation 4 1.7 Electrical Requirements 5 1.8 Water Requirements 5 1.9 Gravity Drain 6 1.10 Drain Pump 7 1.11 Operation in ON position 7 1.12 Operation in CLEAN position 9 2. Sealed System 2.1 Introduction 9 2.2 Low Side Leaks 10 2.3 High Side Leaks 10 2.4 Restricted Capillary Tube 10 2.5 Access Valve 10 2.
1.1 Specifications Cabinet dimensions: Height: 34 to 35 ¼ inches, adjustable Width: 14 ¾ inches Depth: 21 inches (cabinet only) 23 ½ inches (cabinet and door) Weight: 95 lbs. Shipping weight: 100 lbs.
1.2 Serial Nameplate The serial nameplate is located on the bottom flange directly above the grille on all Marvel units. Figure 1.1 gives the information that is provided. The serial number will need to be given whenever parts are ordered or when inquiring about the ice maker. Figure 1.1 1.3 Before Servicing h Power to the ice maker must be off before any attempt to service. This can be done by unplugging the unit or disrupting power to the ice maker receptacle. Verify power is disconnected to unit.
1.4 After Servicing After servicing the unit, whether it is at the site or at service center, check the following: h MAKE CERTAIN THERE ARE NO LEAKS IN THE DRAIN OR WATER LINES. Check the water line, water valve, drain valve, and drain tubing for leaks. h Make certain the ice maker functions properly by observing ice production and ice harvest cycles. Check for hollow ice slabs or ice slabs that will not release. h Make certain the bin thermostat will turn the unit off.
h Area should be ventilated with temperature above 55F and below 90F for proper operation. h Unit must be installed indoors away from the elements of nature. h Unit must be on a level surface capable of supporting the loaded weight of the unit. h Refer to Appendix A, owner’s guide, for additional information. 1.7 Electrical Requirements Electrical Shock Hazard Failure to follow these requirements could result in personal injury, electrical shock, or fire. h 115 VAC, 60 Hz.
The above materials can be found at most local plumbing supply stores or hardware stores. Follow the manufacture’s installation instructions for water valves and water line hook-ups. Make certain the waterline and the valve do not leak prior to enclosing cabinet. 1.9 Gravity Drain OBSERVE AND FOLLOW ALL LOCAL AND STATE CODES WHEN INSTALLING ICE MAKER. A DRAIN TRAP MUST BE USED FOR ICE MAKER DRAIN. FAILURE TO DO SO CAN RESULT IN EXPLOSION, PERSONAL INJURY, OR DEATH.
42242436, Marvel Drain Pump can be used to drain water when gravity drain is not available. Refer to Appendix B for drain pump installation instructions (also supplied with drain pump). As with the gravity drain, it may be necessary to wrap the drain tubing from the ice maker to the inlet of the drain pump with wrap-type insulation. Condensation can form on the drain tubing and cause water damage. 1.11 Operation. Selector switch is in the “ON” position.
Upon setting the switch to the “ON” position, the water solenoid will energize for 1.5 minutes and then de-energize. When the bin thermistor senses temperature at or above the “start ice” setpoint, and the evaporator thermistor senses temperature at or above the “production” setpoint, the production cycle will begin. The circulation pump, condenser fan, and compressor relay will energize. When the evaporator thermistor senses temperature at or below the “harvest” setpoint, the harvest cycle will begin.
1.12 Operation. Selector switch is in the “Clean” position. The assumptions before proceeding are that water is supplied to the ice maker (see section 1.8), there is proper electrical power to the ice maker (see section 1.7), and drain is properly plumbed or the drain pump is operating properly. Refer to timing/operation diagram in figure 1.3.
3. Limit time the system is opened. DO NOT EXPOSE OPEN SYSTEM FOR MORE THAN 15 MINUTES. This will result in sealed system failure. Leave replacement parts sealed and/or pressurized until ready to install. 4. The compressor must be replaced if there is a low side leak. Moisture has been drawn into the system if the unit has been running for extended period of time. Be sure to flush the system with dry nitrogen gas and evacuate to 50 microns before re-charging (see section 2.3, Low Side Leaks). 5.
2.5 Access Valves A temporary access valve can be used to service or evaluate the system. The access valve can be installed on the compressor’s process tube (this will also be a low-pressure side). Be sure to cap off access valve while servicing. This will prevent contamination of the system and/or refrigerant from leaking. After servicing, the access valve should be removed.
14 16 18 20 22 24 26 28 30 32 34 13.1 14.4 15.7 17 18.4 19.9 21.4 22.9 24.5 26.1 27.8 29.5 56 60 64 68 72 76 80 84 88 92 96 100 52.3 57.5 62.7 68.3 74.2 80.3 86.8 93.6 100.7 108.2 116.1 124.3 Table A During production cycle, low side pressures will vary from 125 psi to 3 psi, depending at what point measurements are taken. High side pressures can range from 425 psi to 25 psi also depending at what point measurements are taken.
After recharge, check pressures. Refer to Table A for corresponding temperatures and pressures. If pressures or temperatures are incorrect, check the sealed system, recover the charge, repair, evacuate, and then recharge. NOTE: It is not uncommon to have some condensation or a slight frost on the suction line. This may occur towards the end of the production cycle. Liquid refrigerant is not getting into the compressor if the unit was charged properly.
3.1 Hot Gas Valve The hot gas valve is used to bypass the capillary tube and send warm gas to the evaporator when opened during the harvest cycle. The valve is actuated by a solenoid that opens the valve when energized and closes when de-energized. The valve seats using gravity so the valve must remain vertical to fully close. A faulty hot gas valve will result in long ice production cycles and higher than normal low side pressures.
3. Remove the grille by removing the two screws and disconnecting the three wires to Rear panel Access panel Figure 3.3 the rocker switch. Be sure to mark where these wires go for re-assembly. 4. Remove the drain valve. 5. Remove the water valve. 6. Take out the two screws that secure the top of the electrical bracket located in the front of the mechanical area (see figure 3.4). 7. Remove the six screws that secure the baseplate to the cabinet on the bottom of the unit (see figure 3.5).
9. Install system access valve(s) and recover refrigerant. After recovering, be sure to cap off the access valve to prevent contamination of the system. 10. Disconnect the wires at the solenoid, remove the solenoid-retaining clip, and remove the solenoid (see figure 3.2). 11. Un-braze the brazed union upstream of the hot gas valve (see figure 3.2). Be sure to cap off after tubing has cooled. 12. Un-braze and remove the capillary tube from the drier assembly. 13.
low side tubing is found, the compressor, drier, and hot gas valve will need to be replaced. The temperature control thermistor sets on the bottom of the evaporator plate on a copper bracket. This bracket should be checked at the solder joint. Any cracks will break the proper thermal conductivity between the evaporator plate and the thermistor and result in long production cycle with a thick slab on the plate.
25. Un-braze and remove the suction line at the compressor (see figure 3.8). 26. Un-braze the hot gas discharge line at the compressor (see figure 3.8). Hot gas discharge line Process tube Compressor lock-nut Drier assembly Figure 3.8 Process tube (high side) 27. Remove the compressor by removing the two lock-nuts on the mounting plate of the compressor. Lift the compressor off of the carriage bolts (see figure 3.8). 28.
3.3 Compressor The compressor is the heart of the refrigeration system. It also, however, relies on other parts of the system to function. Make certain that the other parts of the system are correctly functioning before determining that the compressor is faulty. The compressor is protected from power interruptions with a start delay built into the control to prevent high pressure startup (see section 1.11 Operation). DO NOT mistake this for a faulty compressor.
17. Remove the compressor by removing the two lock-nuts on the mounting plate of the compressor (see figure 3.8). Lift the compressor off of the carriage bolts. Installation: 1. Install the four rubber grommets in the bottom of the new compressor and install the two sleeves where the carriage bolts will be located. Mount the new compressor and install the two washers and lock-nuts and tighten to 45 in-lb. DO NOT REMOVE THE RUBBER PLUGS AT THE TUBE STUBS ON THE COMPRESSOR AT THIS TIME. 2.
5. Remove the water valve. 6. Take out the two screws that secure the top of the electrical bracket located in the front of the mechanical area (see figure 3.4). 7. Remove the six screws that secure the baseplate to the cabinet on the bottom of the unit (see figure 3.5). 8. Gently slide the mechanical out the rear of the unit enough to gain access to the condenser coil and fan shroud (see figure 3.6). 9. Install sealed system access valve(s) and recover refrigerant.
Removal 1. Drain water in the reservoir by removing the drain plug or shutting off the water supply and allowing ice maker to cycle through ice harvest cycle. Replace the drain plug, if used, after the water has been drained. 2. Disconnect power, water line, and drain line. If a drain pump is used, it will need to be disconnected and removed. 3. Remove the access panel and rear panel (see figure 3.3). Hose 4. Remove the brown and white clamps wire terminals at the drain valve. 5.
supply, and see if there is any water flowing in the water lines. If water is present and flowing, the valve will need to be replaced. 3. Check the flow rate of the reservoir water line. Using a stopwatch or a watch with a second hand, see what amount of time it takes to fill up a one quart container. The time should be 60 seconds to get the .25 gpm specifications of the valve.
Removal 1. Disconnect power, water line, and drain line. If a drain pump is used, it will need to be disconnected and removed. 2. Remove the access panel and rear panel (see figure 3.3). 3. Remove the grille by removing the two screws and disconnecting the three wires to the rocker switch. Be sure to mark where these wires go for re-assembly. 4. Remove the drain valve. 5. Remove the water valve. 6.
2. Use a reference temperature point that is known (such as an ice bath) and measure the resistance across the wire leads. 3. Check the recorded resistance with that in the table 5.1 below. If measured resistance falls outside the resistance given in the table 5.1 within 4% of the value, the thermistor is bad and will need to be replaced. RESISTANCE VS. TEMPERATURE CHART TEMPERATURE (C) TEMPERATURE (F) RESISTANCE (KOHMS) -15 5 11.350 -10 14 8.918 -5 23 6.700 0 32 5.630 5 41 4.520 10 50 3.652 15 59 2.
The bin thermistor is made up of a soft copper tube body and placed inside a plated copper sensing tube. This plated tube is then secured to the side of the ice maker’s bin to detect the ice bin level. The bin thermistor gives voltage input to the electronic control. This input is processed through the electronic control to switch the ice maker into stop making ice or start making ice. The thermistor must be fully inserted into the plated sensing tube for proper detection.
Installation: Reverse the removal procedure for installation. Make certain that the thermistor’s copper tube is fully inserted into the sleeve. 5.3 Grid-Cutter Transformer The grid-cutter transformer is used to step down the voltage to the grid-cutter to 12 VAC. The transformer is on only from the start of a harvest cycle to 35 minutes from the start of the production cycle.
6.1 Grid-Cutter The grid-cutter is used to cut cubes from the ice slab formed on the evaporator. It uses low voltage, 12VAC, to heat the wires. Wires are warm to the touch of a hand when not under the load of a slab of ice. The grid-cutter is on only from the start of a harvest cycle to 35 minutes from the start of the production cycle (see section 1.11). There is no repair for the grid-cutter. It will have to be replaced as an assembly.
2. Plug the grid-cutter into the receptacle on the side of the liner. Route the plug wire between the reservoir and liner (see figure 6.1). This will keep it away from the path of the ice slab. 3. Re-install the escutcheon panel. Adjustment to the brackets may be necessary to align the escutcheon panel. 6.2 Reservoir The reservoir retains the water needed to produce an ice slab. It will hold a maximum of 3 quarts of water. Anything over 3 quarts will be drained in the reservoir’s overflow.
Installation 1. Slide the circulation pump into the reservoir. 2. Insert the reservoir drain tube fitting to the drain tube in the rear of the liner. 3. Tilt the reservoir forward and line up the screw holes in the reservoir with those of the liner. 4. Insert the spacer to the outside of the reservoir and then the screw and plastic washer to the inside of the reservoir. Repeat for the other side. Water line is away from the path of the ice slab. Figure 6.5 5.
h Check for continuity between the hot and neutral terminals and the pump’s motor casing. If continuity is found, replace the circulation pump. h Check current draw. Typical current draw will be .36 amp without pump resistance. If excessive current draw is found, check the pump’s impeller for foreign particles or severe build-up of mineral deposits. Removal 1. 2. 3. 4. 5. Disconnect power to the ice maker. From inside the unit, remove the escutcheon panel. Remove the grid-cutter (see section 6.1).
Figure 7.1 7.1 Wiring Diagram Figure 7.1 is the wiring diagram for the ice maker. 7.2 Point-to-Point Wire Layout The diagram on the following page, figure 7.2, shows point-to-point termination. This diagram is also located on the back panel of the unit along with the wiring diagram (figure 7.1).
Figure 7.
Notes: - 34 -
8 Ordering Parts The following information will need to be given when inquiring about service parts: 1. 2. 3. 4. Model and serial number located on the serial nameplate (see section 1.2) The color of the model Metal or plastic grille Type of door (replacement panel or standard) To order, call or write: Marvel Industries Customer Service P.O.
