Sparta_Automation Posted July 23, 2014 Share Posted July 23, 2014 I am having an issue with an AP320 frozen machine. Tried to have it fixed a couple of times....and each time it gets worse. Here is my latest problem. The compressor is not kicking on at all. On the FSB, the compressor light comes on, and I can hear the click of the relay, but nothing is happening. This started after the compressor relay was changed on the junction box. The tech changed the relay in an effort to fix a freezing up issue. Not sure why they went this direction, but they did. I put the original relay back in....and it does the same thing. Indicator light comes on, but no compressor. My concern is that when they put the leads back on the relay, the put them to wrong ones. I am hoping that someone can tell me where each goes so that I can verify. Basically, there are 4 sets of wires 2 white 2 black (one black has dual connection) See attached photo. Is this correct? Thanks Travis Link to comment Share on other sites More sharing options...
Technivend Posted July 23, 2014 Share Posted July 23, 2014 According to the schematic the 2 white wires should be on the relay coil. The double black on the center terminal and the single black on the n/o terminal. If I were to guess based on the picture I would move the double black up one lug closer to the single black and move the white wire next to the single black to where the double black was. This is just a guess based on the picture and not seeing the actual relay terminals. Link to comment Share on other sites More sharing options...
AZVendor Posted July 23, 2014 Share Posted July 23, 2014 Sparta, you have a different relay in place from what AP originally put in it. I'm looking at a relay box and the refer relay is a Type 737-1Z-C1 made by Ong Ghuan, whoever that is. The type might cross to the one you now have but you need to verify that and then get the technical specs for yours to see what parts of the relay your terminals are for. On the AP relay there are 6 terminals, 3 on each side and none down the center. With the relay label facing you, the two white leads go on the back two terminals, one on each side. The front terminals aren't used. The double black wire is on the mid terminal of the right side and the single black is on the mid terminal of the left side. Basically the two whites are on the coil and the blacks are switched by the relay actuation. Looking into the relay body you should see that the blacks are on two disconnected terminals that become connected upon energizing of the coil, completing the refrigeration circuit. The relay is switching only one side of the refer power circuit, just like any other cold control would. If the relay is wired properly, the FDB is working properly and the wiring to your cooling unit is intact then you should at least hear the condenser fan come on when the relay is energized. If you don't then your problem is the FDB, the evap fan and/or refrig relay or the cooling unit wiring. As to the freezing issue, the relay will only be the cause if the unit is working properly and just never turning off. This is unlikely and should not be confused with the unit running non-stop because the temperature is too high in the cabinet. The way to check the relay is to remove one white wire from the refer relay and power the machine up. If the refer comes on immediately then the relay is fused and bad. However, an evaporator freeze-up in a 320 can be caused by low freon, a bad defrost harness, bad defrost heater, air leaks in the cabinet (baffle door or inner door latches, seals in refer unit), weak or bad evaporator fan, missing or clogged evap drain hose, machine leaning to the right preventing water from draining or an older style evaporator box that has moisture saturating the side walls. If you need parts for this or more help with the diagnosis then send me a PM with your phone number and I can walk you through some things with it. Link to comment Share on other sites More sharing options...
Sparta_Automation Posted July 24, 2014 Author Share Posted July 24, 2014 Thanks for the input AZ....as a additional note, the tech that worked on this unit ordered a replacement relay from veii (not the one shown in the picture) and put it in and this is when the issue with the compressor not working started. The one he put in from VEII is the one you referenced (same p/n). Now imagine the same picture as above....with the leads like this on the correct relay (this was the way he installed it) With the label facing me: Back left Terminal - White Lead Back right Terminal - Double Black Lead Middle left terminal - White Lead Middle right Terminal - Single Black Lead With the info you provided, I will reconnect correctly and give it a whirl. Hopefully that will fix at least one of my problems. I will PM you if parts become needed. Travis Link to comment Share on other sites More sharing options...
AZVendor Posted July 24, 2014 Share Posted July 24, 2014 I'm thinking your tech isn't too good with the AP320's because if he used a proper replacement relay and connected it wrong then it might be possible to burn up the relay. Link to comment Share on other sites More sharing options...
Sparta_Automation Posted August 17, 2014 Author Share Posted August 17, 2014 ok, so put the wiring back to what it should have been, but the internal fan would not turn on. The unit was frosting, but not cooling the cabinet. checked and replaced the relay for the fan and it worked......for about 6 hours. Now have a different problem and of course the tech manual is horrible for error messages. This is what happened. Got the unit running, compressor kicked on and the fan was working. Went away for an hour or so and when I came back, the unit was at -15 and the compressor was running. Checked the setting and it was programmed to chill to -15. Changed the programming to keep it about -8 and the compressor kicked off as expected. Came back about 5 hours later and the unit was off-line, lights out and the temp showed -- Checked for error messages and it says there is a comm error with cab1. Tried to cycle power and start the unit again and the compressor will not start. The Status light on the FSB will blink for a minute or two on power up, but then goes to a solid light. Looking for suggestions on what to try now. BTW, I am a very stubborn person and I do not give up easily Travis Link to comment Share on other sites More sharing options...
AZVendor Posted August 17, 2014 Share Posted August 17, 2014 A comm error will either be a bad MDB harness between the machines, a bad FDB or a bad logic board in the master. First check for any damage to the exposed harness between the machines and any visible parts of the harness inside both cabinets. Look for cuts in the insulation. Also, in the frozen cabinet, look closely at all harnesses leading to the FDB and particularily at the 110v cord to ensure the cord is at a right angle to any other harness where they cross each other. The current draw through the power cord can set up strange harmonics in any other harness if the cords are parallel to each other. If the MDB harness is okay then try a new FDB. If the problem and comm error persist then try a new main logic board. Just to clarify, the fan you're referring is the evaporator fan blowing up the back of the cabinet, correct? Also look for any burned or loose connectors where they all plug into the relay box. The 110v plug will discolor, blacken and become very brittle from the current pulled by the compressor. Unplug the frozen machine and after inspecting the plugs, take a small flat blade screwdriver, work it into each female pin opening of the power cord and slightly close each female pin so when the connector is pushed back in, the pins will make tighter contact with the male pins from the relay box. Make sure there is sufficient airflow through the condenser, if you can get it to run again, by placing a sheet of paper up against the condenser to see if it is pulled hard against the fins. If not then the condenser is probably clogged with embedded dirt. Blowing it with a compressed air hose, a CO2 cylinder hose or removing the unit and ashing with a strong stream of water are the only ways to clean it. Now, with all of this said, you could also have a compressor problem if the compressor can't restart when it's hot. This will cause the health control error that turns off the lights. You should have had a health error if your temperature got too high. Link to comment Share on other sites More sharing options...
Sparta_Automation Posted August 17, 2014 Author Share Posted August 17, 2014 I will check those items tomorrow and will post results. Yes....I was referring to the evaporator fan. Thanks again for the help! Travis Link to comment Share on other sites More sharing options...
chris in bc Posted August 17, 2014 Share Posted August 17, 2014 Did you buy this machine used? Is there a 20 amp plug at the end of the machine? Do you know what a 20 amp plug looks like? Is the machine plugged into a dedicated 20 amp plug in the wall? Is your air intake screen blocked from dust, debris, dirt and even newspapers from a dirty lunchroom? Link to comment Share on other sites More sharing options...
Sparta_Automation Posted August 18, 2014 Author Share Posted August 18, 2014 I have had this machine for about 3 years now.....and it was a used machine when I purchased it. As soon as I got it, I installed a refrigeration update kit and it ran for about a year with no issues. It's only been recently that it has started to have issues. The unit is away from the wall and the bottom filter is clean. It is in a dedicated 20 amp circuit. Travis Link to comment Share on other sites More sharing options...
chris in bc Posted August 18, 2014 Share Posted August 18, 2014 Is the glass warm? Shut the power off ...wait 30 seconds. Inspect all the connections on the junction box and especially on top of the junction box. Check to ENSURE none of the connections have shorted out ( they will be black), LOOOOOOOOK at every pin, connection, follow the wire from the junction box as far as you can with 3 fingers sliding along each wire and check for breaks. Take the FSB board off, does it smell like burnt plastic? Are all the connection made, look at the pins under a HIGH powered light-are they bent, broken, missing, busted..anything? If not call CRANE tech support and ask for MIKE! Link to comment Share on other sites More sharing options...
rmorris1953 Posted August 18, 2014 Share Posted August 18, 2014 I have not chimed in yet because I have only worked on a couple. I have rebuilt the deck and have replaced evaporator fan motor. If it were me I would locate the harness going to compressor. First I would disconnect it and put a Volt meter on connection and check for voltage. If there was voltage (120V) I would then make a harness with a male plug I could plug the compressor straight into a extension cord and see if the compressor runs. This would allow you to hear it without any other noises. It is possible that the start relay or capacitor has burned up. That deck isn't to hard to get out. It is heavy tho. If compressor does run then problem is in electronics. Link to comment Share on other sites More sharing options...
Sparta_Automation Posted August 20, 2014 Author Share Posted August 20, 2014 So a quick update......and the drama continues with this unit. I went back down and turned the machine back on. Everything started as normal, it pulled the temp down as expected, the compressor cycled on and off to regulate the temp. I checked the next morning and it was off line again, temp was at 30 degrees and the evaporator fan is not working again. Messed around with it some more...but could not get the fan going. At least this time it was not a comm error Next step is to pull the deck and open the unit, verify that there is a good and stable connection for the fan power. To answer the question, yes, the glass stays hot. This is an older junction box, all of the connectors are on the sides. I am considering replacing all of the cabling as well as the junction box cables/connectors to eliminate any potential areas of failure. Travis ....Also, I can power the various compressors directly with a cheater cord and the unit kicks on as expected. Link to comment Share on other sites More sharing options...
AZVendor Posted August 20, 2014 Share Posted August 20, 2014 You mentioned before that when you got this machine 3 years ago you installed updates to the machine. Did you only install refrigeration updates? What parts did that entail? Did you ever replace any of the gaskets on top of the unit or between the foam block and the evaporator box? Did you add sufficient putty to the freon line opening in the evaporator box? Since you mention that you have side mount harness connectors, that means you have a very early 320 with the relay box mounted to the front of the evaporator box. All of the updates to a machine of that vintage include new inner door latches, a new door switch and actuator, a new evaporator air duct with nylon hinges, a new evaporator harness with a red connector to the relay box, a new drain hose with an elbow at the end and a new evaporator fan with red rubber at the ends of the squirrel cage. There is a newer eprom for the FDB, version 2.1, that eliminates baffle door issues in the previous eproms. There is also a redesigned evaporator box that is more shallow with a more steeply angled floor for better drainage along with a new drain hose that has a P-trap in it. If your box has never been replaced you probably have moisture that has wicked into the walls and frozen in place, causing havoc with your defrost cycles. If the walls of the evaporator box feel cold then you have moisture in the walls and need to replace the box. Is the cheater harness you mentioned the factory AP test harness for this unit? If not then you can't properly bench test the unit. Is the baffle door sealing against the inner door properly? Does the baffle door move smoothly and open and close with little effort? You can lube the baffle door tracks with white lithium grease when the door is open. Check for an air gap by looking up at the surface of the inner door where the baffle door meets it. There should be no light visible anywhere along that surface. Now run manual open and close routines of the baffle door 10 times and recheck the gap. When adjusted properly make sure the nuts at each end of the adjusting rod are tight and that the nut connecting the rod to the baffle door motor is tight. I'm bothered by the fact that you aren't apparently getting any errors when the machine goes warm. I would expect a Defrost Error, Switch Error (Bi-metal) or a Health Control Shutdown at the very least, maybe even a Temp Sensor Error. I also think the previous Comm Error is an indication of a logic board issue. If any part causes the unit to fail cooling then one of those errors should be recorded with a date and time (accurate only if you have a good battery on the logic board and you have properly set the date and time) and duration of the event. Either you're not seeing the errors that exist or something is wrong with your logic and/or food driver board. You need to ohm out the components in your cooling unit. You can do that from the evaporator harness plug (red one). Hold the plug while looking at the wire side and with the plug latch on the left side. The terminals are numbered from top to bottom. The left side going down are 4, 5, 6 and the right side going down are 1, 2, 3. Make the following resistance measurements on your lowest scale: Evaporator fan - pins 4, 5 should be 10 ohms (+/- 3) Defrost heater element - pins 5, 3 should be 22 ohms (+/- 4) Bi-metal switch - pins 1, 2 should be open if the unit is warm or closed if the unit is cold. The test for the actual cooling ability of the unit is performed with the unit out of the machine. Find a box that is the correct size (14" x 14") to fit upside down around the gasket on the evaporator top with no gaps around the edges and that fits flush against the sheet metal. Push a probe thermometer into the bottom of the box for this test procedure. Remove the evaporator top metal and foam so that you can view the evaporator coil. If you have an Amp Probe, clamp it around the single black wire leading from the test cable to the compressor power, and using the factory test cord, power up the compressor only in. Upon startup you will see a spike of about 15-18 amps that will then lower to about 12 amps as it runs. There should be good airflow from the condenser fan and the compressor should not exhibit any difficulty starting or running. Within 5 minutes all of the elbows of the evap coil should be frosted up (use a flashlight) and the surface of the coil should be frosted. Now plug in the remaining test cable plug so the evaporator fan runs. There should be strong even air flow and the air duct flap should open easily. Unplug the evap fan and check that the duct flap immediately slams closed. Restart the fan and after a few minutes only the bottom rows of copper elbows on the coil should remain frosted (use a flashlight). Inspect the expansion valve next to the coil and look for any mushroom shaped deformity. Now place the evaporator top with the foam block back onto the evaporator box without securing it. Make sure it is pressed tightly down. Set the cardboard box on top of the evaporator inlet and outlet and hold the box down to ensure a tight air seal. Within 13 minutes the temperature inside the cardboard box should reach -10 degrees. If all of these tests pass then the cooling unit is functioning properly. You will need to reinstall the unit after properly sealing and securing the evaporator top to the box and run the machine to a frozen temperature. At that time you need to force a manual defrost. As the defrost cycle starts, put your ohm meter probes on pins 1 and 2. You should have continuity between the pins as the unit is currently cold. Now monitor the voltage to the defrost heater by putting your voltmeter probes into pins 5 and 3 on the wire side of the red evaporator plug. The voltage should be 110-115v while the defrost LED is lit on the FDB. When the defrost cycle ends, the LED goes out and voltage drops to zero, open up the inner door and pull the bottom shelf so you can feel the top fins of the evaporator to see if heat is rising from it. At this time also use your ohm meter again on pins 1 and 2 of the evaporator plug to see if that circuit is now open (no resistance) due to the warm evaporator box. Again, if all of this checks out then you should try replacing the logic board and FDB one at a time to see if you can eliminate your cooing failures with the replacement of one or the other boards. Link to comment Share on other sites More sharing options...
chris in bc Posted August 20, 2014 Share Posted August 20, 2014 Have you moved the machine lately? Was it knocked around, pushed around....did the customer renovate the area? I have a feeling your MDB cable could be damaged cause you ain't getting no errors on your display! MDB cables are $55 bucks from vendors exchange! Link to comment Share on other sites More sharing options...
rmorris1953 Posted August 20, 2014 Share Posted August 20, 2014 So a quick update......and the drama continues with this unit. I went back down and turned the machine back on. Everything started as normal, it pulled the temp down as expected, the compressor cycled on and off to regulate the temp. I checked the next morning and it was off line again, temp was at 30 degrees and the evaporator fan is not working again. Messed around with it some more...but could not get the fan going. At least this time it was not a comm error Next step is to pull the deck and open the unit, verify that there is a good and stable connection for the fan power. To answer the question, yes, the glass stays hot. This is an older junction box, all of the connectors are on the sides. I am considering replacing all of the cabling as well as the junction box cables/connectors to eliminate any potential areas of failure. Travis ....Also, I can power the various compressors directly with a cheater cord and the unit kicks on as expected. Customer bought one refurbed and when it arrived it didn't cool. I determined it was the junction box. They sent another one and it didn't work. I was puzzled so I turned the original one over and was looking at the relays and noticed one of the relays had come loose. After that except for a $175.00 evaporator fan motor it worked great. Link to comment Share on other sites More sharing options...
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