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Topic Review (Newest First)

  • 01-06-2013, 11:49 PM
    cavalieri85
    Really need to start looking at the dates on threads!!!!!!!!
  • 01-06-2013, 10:50 PM
    trippintl0
    Quote Originally Posted by J_Bridge View Post
    Guys, he jumpered the float switch. This eliminates any water issues and goes back to a board issue or a connection. I would agree with craig1 and check the board. You have jumped the wire connections and therfore bypassed the switch and its wires.
    Hopefully he already fixed it 5 years ago when he posted the question? Ha ha ha! Just giving you a hard time.
  • 01-06-2013, 09:47 PM
    J_Bridge
    Guys, he jumpered the float switch. This eliminates any water issues and goes back to a board issue or a connection. I would agree with craig1 and check the board. You have jumped the wire connections and therfore bypassed the switch and its wires.
  • 01-06-2013, 09:11 PM
    cavalieri85
    Could also be a faulty water inlet valve not adding proper amount of water at fill cycle
  • 01-06-2013, 07:49 PM
    craig1
    If just messing around with it made it start working, I would go over the back of the board with magnifying glass and check for cracked solder joints, particularly at the float switch connection.
  • 01-06-2013, 12:09 PM
    Straits

    Short freeze cycle

    Quote Originally Posted by mister frío View Post
    This machine is going to drive me crazy! Today I got so fed up with it I pulled out the control card and all the wiring. I checked every single component on the machine, right down to the on/off switch. On a workbench I wired up the transformer to the board, and ran the diagnosis cycles again with plenty of room to watch what happened. I put the tester across the 4 relays and watched them open and close, as well as checking the pin continuity on K1.

    The only out-of-the-ordinary thing was that the (downloaded from Hoshizaki) manual indicates that there are FIVE relay/pin checks, activated by bridging the float switch terminals FIVE times. But on this board, the relays cycle after FOUR bridges, omitting the second bridge shown in the manual. Perhaps it's an updated manual and I have an out-of-date board.

    Anyway... Close to 6 p.m. satisfied that everything else worked just fine, I rewired the machine (somewhat tidier than before), fired it up and was surprised that it ran a full cycle perfectly normally! I only ran one cycle because it was getting late.

    Now I have another problem, if the machine works just fine tomorrow. I didn't actually "fix" anything, it just started working. I'll have to keep it running in the shop for at least another week before I can return it to the customer with any degree of confidence.

    Maybe it was just a loose connection, but I'd sure like to know which one!

    I'll keep you posted on tomorrow's results.

    Thanks guys. Greetings from Venezuela.
    I had the the same problem with mine. During the freeze cycle, check to see if water is coming out of the drain line. If it is, then the tank is emptying prematurely causing the float to sense that it is time to start a new cycle. The cause was the pump out valve was not seating properly. It is completely manual and has no electrical sensors. It is located behind the float with three screws. Remove them and pull it out. Clean the rubber seal and check for debris and make sure the spring is good. Replace if necessary. Reinstall. During the freeze cycle verify that no water is coming out of the drain. Worked for me and was a cheap fix.
  • 08-23-2007, 11:09 PM
    ckone180
    Quote Originally Posted by jtrefrig View Post
    i am sorry i am new to this site. i meant they only fill one time per cycle unlike manis that can fill multiple times up to 5 mins or so. i meant one time per freeze cycle. jbb
    It was an attempt at shorthand, and you are correct, the Hoshi is water level based and the Manitowoc is thickness based. I will need to be exact next time, like everyone else, hmmm.....
  • 08-23-2007, 09:59 PM
    jtrefrig
    i am sorry i am new to this site. i meant they only fill one time per cycle unlike manis that can fill multiple times up to 5 mins or so. i meant one time per freeze cycle. jbb
  • 08-23-2007, 07:38 AM
    ckone180
    Quote Originally Posted by wannafreeze View Post
    During the harvest it energizes the WV to assist harvest(6 min.max).
    Then again by the time harvest is complete float should be closed.Without a one min fill cycle the next freeze will start.
    It is doing both, assisting harvest and filling the reservior. Or easier said, second fill. Hmmmmm.
  • 08-22-2007, 11:20 PM
    wannafreeze
    Quote Originally Posted by ckone180 View Post
    When that unit calls for the second fill it goes into harvest. Just a thought.........
    During the harvest it energizes the WV to assist harvest(6 min.max).
    Then again by the time harvest is complete float should be closed.Without a one min fill cycle the next freeze will start.
  • 08-22-2007, 10:11 PM
    ckone180
    Quote Originally Posted by jtrefrig View Post
    hoshis dont have a second fill. if u jump the float and it still goes in at 5 min order u a board. also check txv bulb clamps. they are problably rusted with would explain your high suction. peace out jbb
    Yes it does, it has to fill during the harvest cycle to have sufficient water for the next cycle........huh?
  • 08-22-2007, 09:20 PM
    mister frío

    Hoshizaki update...

    This machine is going to drive me crazy! Today I got so fed up with it I pulled out the control card and all the wiring. I checked every single component on the machine, right down to the on/off switch. On a workbench I wired up the transformer to the board, and ran the diagnosis cycles again with plenty of room to watch what happened. I put the tester across the 4 relays and watched them open and close, as well as checking the pin continuity on K1.

    The only out-of-the-ordinary thing was that the (downloaded from Hoshizaki) manual indicates that there are FIVE relay/pin checks, activated by bridging the float switch terminals FIVE times. But on this board, the relays cycle after FOUR bridges, omitting the second bridge shown in the manual. Perhaps it's an updated manual and I have an out-of-date board.

    Anyway... Close to 6 p.m. satisfied that everything else worked just fine, I rewired the machine (somewhat tidier than before), fired it up and was surprised that it ran a full cycle perfectly normally! I only ran one cycle because it was getting late.

    Now I have another problem, if the machine works just fine tomorrow. I didn't actually "fix" anything, it just started working. I'll have to keep it running in the shop for at least another week before I can return it to the customer with any degree of confidence.

    Maybe it was just a loose connection, but I'd sure like to know which one!

    I'll keep you posted on tomorrow's results.

    Thanks guys. Greetings from Venezuela.
  • 08-22-2007, 09:01 PM
    mister frío

    Thanks, DoctorIce....

    ...that's a really generous offer. If you were a bit closer I would gladly accept, but there are a few snags with sending anything:

    1. We don't have a regular mail service worth the name. My sister in the UK regularly sends me stuff, and only about 50% of it gets here, and the other 50% takes up to six months and a great deal of sleuthing to get hold of. So if it's anything important she has to use FedEx or similar.
    2. The cost of your shipping a board to Venezuela via FedEx would probably be pretty high, and I'd hate to put you to that expense.

    When I order parts from the U.S. I have to specify courier delivery and pay extra. That hurts, because we have strict currency control here, and I have to buy US dollars on the black market at double the real value.

    However, it's great to know that there's a helpful guy like you up there in Canada. If you're ever down in my neck of the woods, count on somewhere to stay. As they say down here, "Mi casa es tu casa".
  • 08-22-2007, 08:20 AM
    DoctorIce
    I have a fair number of used Alpine boards. I prefer them to the new board when the machine starts having harvest problems. Could I send you a used board (checked out of course) without causing a lot of customs problems?
    I'll send it for free but should I put a value on it?
  • 08-21-2007, 11:33 PM
    mister frío

    Thanks, JTRefrig...

    I'll check out those clamps. Good advice.

    Greetings from Venezuela.
  • 08-21-2007, 10:41 PM
    jtrefrig
    hoshis dont have a second fill. if u jump the float and it still goes in at 5 min order u a board. also check txv bulb clamps. they are problably rusted with would explain your high suction. peace out jbb
  • 08-21-2007, 10:25 PM
    mister frío

    Thanks, Ckone180...

    "When that unit calls for the second fill it goes into harvest. Just a thought..."
    I've had a few headaches with this particular machine, and that was one of them. For starters, the new pump would only run in "reverse", and would pump the machine dry within a couple of minutes of starting the freeze cycle. I didn't notice it at first, but when I did I assumed it was the check valve leaking. The spring looked fine, but I stretched it a little, anyway. Spring seating is fine, and the rubber seal is in good condition.

    There followed a period of two hours when I thought several times about hitting the damn thing, because the pump wouldn't run forwards to circulate the water. I tried several "experiments" to get it to to run both ways before I discovered that it was a defective capacitor. First time I've come across that problem. Anyway, it was now solved, and it runs backwards AND forwards just fine, with no leaks from the check valve.

    So now there's plenty of water in the tank when the machine goes into the harvest cycle after the 5-minute lock-out. I checked that the float switch was closed, too, as I suspected it might be sticking open and faking an empty tank.

    Despite the board diagnostics checking out OK, it's sounding more and more like an electronics problem, isn't it.

    The only other obvious thing that I need to get to eventually is a higher-than-usual suction pressure. With 90ºF air and 75ºF water I'm starting the freeze cycle with 72 PSI and 250 PSI discharge. I suspect that the hot gas bypass is leaking, but I can't see how that might affect the switchover to harvest after the first 5 minutes.

    Thanks from Venezuela.
  • 08-21-2007, 09:22 PM
    ckone180
    Quote Originally Posted by mister frío View Post
    "Pull the float switch connector and put a jumper across the board terminals."
    Did that first. It's not the float switch, I'm pretty sure of that. Anyway it's brand new. Thanks for the suggestion, though.

    On another subject, the icemaker project we talked about a couple of months ago is still alive. Found someone to make the evaporators for me. Learned how to calculate the heat load and size the compressor (thanks to your tips and links). Designed the control system. Now to design the casing, get the bits put together, and build the prototype. I'd like to have one made by Christmas. I'll keep you posted.

    Best wishes from Venezuela.
    Just a thought, but, if you have plenty of water and the float is good, check the check valve for the drain. They are the triangle shaped plastic part the pump has a tube going to. You have one inlet tube for the pump and two outlets. One outlet sends water through the top section for evaporator and the other sends it down the drain when the pump is reversed. When the check valve is partially held open the water will be forced down the drain causing the float to break and call for fill. When that unit calls for the second fill it goes into harvest. Just a thought.........
  • 08-21-2007, 09:08 PM
    mister frío

    Hi Icemeister...

    "Pull the float switch connector and put a jumper across the board terminals."
    Did that first. It's not the float switch, I'm pretty sure of that. Anyway it's brand new. Thanks for the suggestion, though.

    On another subject, the icemaker project we talked about a couple of months ago is still alive. Found someone to make the evaporators for me. Learned how to calculate the heat load and size the compressor (thanks to your tips and links). Designed the control system. Now to design the casing, get the bits put together, and build the prototype. I'd like to have one made by Christmas. I'll keep you posted.

    Best wishes from Venezuela.
  • 08-21-2007, 09:00 PM
    mister frío

    Mojo and DoctorIce

    Thanks, guys.
    It's an Alpine board on a oldish machine. Ran through the board diagnosis in the manual, and everything checks out fine.
    Parts for icemakers are expensive and hard to get here, so I don't carry a spare board, though it makes a lot of sense. I'll have to send to the U.S. for a new board if that turns out to be the problem.
    Whatever machine I'm working on, I always pray it's not the control board failure. I can repair most of the electromechanical parts, or replace them with something similar, but the boards are a big problem.
    I've rebuilt machines, replacing the electronics with electromechanical parts, or using stuff like the Danfoss controllers, but Hoshizaki logic is a bit tougher to simulate.
    I'll check out those air holes, Doc. And the Orinoco water, too. Maybe there's a Piranha fish stuck in the float switch.

    Best wishes from Venezuela.
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