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  1. #1
    Join Date
    Apr 2014
    Location
    Westwego, La
    Posts
    7

    I WANT TO SHOOT THIS MANITOWOC QY1305 - Pressure & Harvest Issues

    Let me start by saying that I've worked on a lot of commercial refrigeration equipment in past years. I never got to the point that I considered myself a specialist in the field. I veered away from it because the time to pay ratio was too low. So often you have to baby sit the equipment and then folks flip out over the bill. Then they either refuse to pay all of it, argue and bit** about it, pay it and never call you back, or you simply don't charge for some of your time, they shake their head say man and pay you. Obviously there's other issues like finicky units that you have to keep going back to adjust over and over again, etc. With years more experience I'm sure some of the problem children would have been easier but comparatively commercial HVAC is where it's at. Of course that's my opinion. Others may feel different.


    Man that was a lot of b.s. Had to stop for a Crown & Coke after that. So here it is:


    History:
    Keep in mind that this is at a friends bar where every friggin body knows how to fix every dam thing and sticks their 12 drunken cents in, and their hands when I'm not there.

    Harvest indicator led lights up prior to consistent contact with the ice. Removed the probe and held it with insulated pliers and the harvest led stays lit. Sometimes touching the probe wire approx 12" away from the probe would cause the led to light. While removing it from the spray tube it blinked on and off depending on contact with my hand and the grid but also just with my hand - while not grounded - wearing rubber soled shoes. I can see grounding to the grid via my hand but not just my hand with me not touching anything else. I rigged it with electrical tape for testing and it stopped messing up - so I left it. A few months go by and it's doing it again. So probe or pcb? It seemed the probe was far too simple a design to be defective but I changed it ( I tried cleaning it first ). Worked fine for a few months until a new but seemingly related fault appeared. I have to add that as mentioned above the resident drunk mechanics, carpenters, electricians, nurses, etc all bent the probe contact and adjusted the screw in their stuppered attempt to "fix it".

    During this period it I discovered the horizontal grid strips are coming loose. Oh that's what all that grey gritty stuff is that keeps collecting in the trough is – solder ( or nickel ). So amazingly enough a fella that works on ice machines ( for real ) was there and had seen it before. He showed me that you can flush the grid strip and carefully pop it with a #2 phillips screwdriver where the horizontal and vertical meet and it would compress the metal to make it hold. Since then I have had to keep doing that as I found new uneven spots.

    The ice bridge was now too thick. Like 1/2" too thick. So I checked the probe and adjusted it leaving express instructions not to let anyone touch the machine – again. Solved for a week. Adjusted it again. Solved for a month. Adjusted it again. This went on for about two months. Each time pulling the curtain and watching the ice grow. While all this was happening the unit would shut down and the owners or employees would pull the power and reset it and call me hours later. So I never got to see exactly what was happening immediately after it shut down.
    Finally i get there and find the ice sheet has partially dropped and is stuck to the grid about 3” off at the top and fully in the grid on at the bottom. The curtain was open about an inch at the bottom from the top of the ice sheet and the probe, being jammed against it.

    I cleared the ice and reset the unit. The ice pattern was very light at the top left and the harvest was slow and incomplete. The sheet was hanging up. Again I cleared the ice. Figuring the coil was starving for refrigerant I hooked up the gauges. I checked the service manual for operating pressures ( realizing they are at a given set of water and ambient temps ) and compared them to my actual pressures. I found the suction and head pressures too low in both freeze and harvest.

    So I obtained some non stock R404A and went to chargin. I brought my pressures up to the bottom side of the mfg op temp ranges and watched. The sheet now formed complete but still a little thinner at the top left than the rest ( i figured the top would be thinner anyway if it was the outlet end of the coil ). I watched it drop several times and decided I had done enough work to go with my free double Crown & Cokes. So I wrapped it up to let it run, colder from being closed, to see what happens.
    A few days go by and I get the call - “Dave the stupid ice machine is not making again”. I get there and it's coded out / off. I reset it and watch it making a pretty good sheet of ice but not harvesting in time. As programmed it went through three cycles with no harvest in 3.5 ( actually 3 min as I timed it ) and coded out shutting down.

    CURRENT:
    The first thing I did was reset the unit and sat with a note pad recording pressures, times, thicknesses and anomalies. The pressures I found showed the freeze pressures were pretty much were where I left them the last visit but the harvest pressures were too low. I broke out the orange can and brought the pressures up. So now my freeze suction pressure is in good in range of the serv man but the high side is avg 320psi. My harvest pressures were at avg. 73 and 150. Now the sheet drops perfectly. Not liking the high head I watch it go through four cycles in perfect time. I disconnect to research the head pressure issue and the dam sheet fails to drop all the way again. So I clear the sheet, hook up the gauges again and see that the harvest suction is now at like 65psi. All the other pressures stayed close to the last readings.

    At this point I'm done for the night. I might mention that this time, as hard as it was, I refrained from drinking until I was done. So I picked up my s*** and had my drink – or two – or three.

    So that's where I'm at. I called the owner and she reported that it's not making near enough and that she has had to reset it several times. Haven't been back yet.

    I don't know exactly what the condenser inlet or outlet water temp was. I estimated it ( with my digital finger probe ) at 65 entering and 110 leaving.

    The production water is on the same tap so it's estimated to be the same.

    The condenser water regulator was seeping now it's a constant drip.

    Water pressure was not measured but the flow is about the same as when it was working normally

    It's clean.
    The grid is even.

    It is inside and obviously water cooled.

    It is almost level - lol.

    The compressor changes sound about 30 seconds into harvest and about 2.5 min into harvest. Though the pressures didn't change with the sound. Sounds are like loading and unloading.

    I'm sure I mis-spelled, mis-stated, omited and otherwise....................................... and GO!

  2. #2
    Join Date
    Mar 2013
    Location
    Springville, NY
    Posts
    2,732
    sell a new one?
    ~~
    Nest is poo...

  3. #3
    Join Date
    Aug 2002
    Location
    manitowoc wisconsin
    Posts
    4,943
    Quote Originally Posted by HVAC_Marc View Post
    sell a new one?
    good advice! evap is junk & where is the gas going?likely the cond is leaking.
    Take your time & do it right!

  4. #4
    Join Date
    Aug 2002
    Location
    manitowoc wisconsin
    Posts
    4,943
    Quote Originally Posted by HVAC_Marc View Post
    sell a new one?
    good advice! evap is junk & where is the gas going?likely the cond is leaking.
    Take your time & do it right!

  5. #5
    Join Date
    Oct 2011
    Location
    Austin, TX
    Posts
    158
    Once that nickel comes off that evap it's time to get a new machine.

  6. #6
    Join Date
    Dec 2003
    Location
    Citrus County, Florida
    Posts
    1,507
    Quote Originally Posted by SeanH View Post
    Once that nickel comes off that evap it's time to get a new machine.
    And make it a Hoshizaki
    Doug

  7. #7
    Join Date
    Jun 2008
    Location
    NW Florida
    Posts
    707
    did you find freon leak? Would recommend a nitrogen pressure check and check at outlet of condenser water. Check and see if hot gas valve is sticking. But like what was posted earlier. Manitiwoc. Do not work when the nickel comes off plate. Hoshizaki is a much better machine. Stainless steel plates (no nickel). Machines are more expensive. But extremely reliable. Seen one that ran for 7 years without anything but water filters being changed and air filter cleaned.

  8. #8
    Join Date
    Apr 2014
    Location
    Westwego, La
    Posts
    7
    "sell a new one?" - That's exactly what needs to happen. Unfortunately the owners husband had an massive aneurism and passed away ( RIP Mark ). Between the funeral and burial and funeral expenses and the loss of subsidizing income from their fabrication shop the money's not there right now. I'm just trying to keep her going until she can level things out.

    "good advice! evap is junk & where is the gas going?likely the cond is leaking." - Agree & I'm not 100% sure it actually was low on refrigerant yet. Wondering if gas was bypassing somewhere. The high head pressure makes me doubt the leaking idea. But definitely must be strongly considered.

    "Take your time & do it right!" - Agree. Because I haven't been charging labor I've put paying jobs first and its left me to be doing the work late and tired. That's why on the last visit I took my time spending several hours watching and recording info.

    "Once that nickel comes off that evap it's time to get a new machine." - Agree

    "And make it a Hoshizaki" - Thanks

    I've made this a personal challenge ( cause it ain't paying nothing - and cause I care ). I know the thing's not worth putting any money into but I'd like to hopefully keep it going till I can find her a good used replacement or her money gets right enough for me to sell her one at cost.

  9. #9
    Join Date
    Jun 2009
    Location
    DFW, TX
    Posts
    664
    If they can't afford a new machine, get a used one. You're not going to fix this without spending some money.

    Descale the evaporator (since obviously they aren't going to replace evaporator). Replace water regulating valve, harvest valve, and drier. Don't forget to descale probes too. And TAKE POWER AWAY from board after cleaning so board can recalibrate. Pull a vacuum, WEIGH in a virgin charge, and use proper technique to bleed liquid from high side hose back into low side, so you don't end up being low on charge! I also recommend replacing machine but I understand the situation.

    BUY a case of food grade silicone the customer can spray on the evaporator every morning. This will help that garbage evaporator to harvest better. OH AND DEFINITELY change dump valve to. It's probably intermittently leaking by causing an evaporator freeze up.

  10. #10
    Join Date
    Jun 2013
    Location
    N. Canada
    Posts
    395
    Quote Originally Posted by trippintl0 View Post
    If they can't afford a new machine, get a used one. You're not going to fix this without spending some money.

    Descale the evaporator (since obviously they aren't going to replace evaporator). Replace water regulating valve, harvest valve, and drier. Don't forget to descale probes too. And TAKE POWER AWAY from board after cleaning so board can recalibrate. Pull a vacuum, WEIGH in a virgin charge, and use proper technique to bleed liquid from high side hose back into low side, so you don't end up being low on charge! I also recommend replacing machine but I understand the situation.

    BUY a case of food grade silicone the customer can spray on the evaporator every morning. This will help that garbage evaporator to harvest better. OH AND DEFINITELY change dump valve to. It's probably intermittently leaking by causing an evaporator freeze up.
    Ya, get a used ice machine, what a thought!

    Come to think of it-that lady will have a used one to sell... the one that yr working on!

    Shotgun parts replacement, then you discover that the coil IS leaking.

    1: Manitowac is passe... depends on gravity working at a 45deg angle to slide ice off a nickeled grid that some cheapskate ruined with non-approved cleaner.

    2: Water (headpressure) regulating valve cannot leak by for proper harvest.

    3: Old water coil probably leaks, hi head pressure due to scale buildup.

    4: Ice thickness sensor will drive you nuts. Microscopic cracks in wire, mineral buildup, will give you that 8k ohm or whatever to premature ejac...

    I would politely suggest that they buy their ice while saving for a new unit.

    Then buy a Hoshizaki... if they buy another manitowac, hand them your competition's business card.
    If you do that enough, they will no longer be in business (ck your lost time).

    I do commend you for your kind heart.

  11. #11
    Join Date
    Oct 2012
    Posts
    3,499
    Manitowoc's aren't that bad.


    But I agree, if the nickel plating is coming off the evaporator and the rows are starting to separate its a lost cause.

  12. #12
    Join Date
    Jun 2013
    Location
    N. Canada
    Posts
    395
    Quote Originally Posted by Mike19 View Post
    Manitowoc's aren't that bad.


    But I agree, if the nickel plating is coming off the evaporator and the rows are starting to separate its a lost cause.
    I wonder if non nickelsafe cleaner has anything to do with the grid separation?

    I note yr location & best stop stomping local mfg!

  13. #13
    Join Date
    Jun 2009
    Location
    DFW, TX
    Posts
    664
    Water regulating valve is already bad (and the gasket for the bellows is common place for refrigerant leak, much more so than the condenser.) Dirty, old dump valves are worthy of replacement just because.

    I would bet that the high head is due to overcharge or clogged water regulating valve rather than dirty condenser.

    Harvest valve may not be necessary, I am just guessing on that one. It just sounds like this is an old, neglected ice machine that belongs in the trash, that's why I wouldn't touch it until the owner is ready to spend some money...

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