Hoshizaki Problems

[skrewdriver]

I got my butt kicked by a KM-1300SAF today. I'm a 6 year hvac tech with no experience on ice machines. The board had been going into a 3 beep alarm. I checked the FS, water inlet solenoid, and check valve, all seemed okay. I was getting tech support from a guy who told me to change the hot gas valve. After doing that I started it up and was running a high head pressure. I had already sprayed the coil out with nitrogen as much as I could until the people in the store yelled at me, than I pulled the fan and brushed the rest out. My pressures(404A) five minutes into the freeze cycle were 325 and 59 with 83 degree incoming water and 82 degree ambient air. 35 minutes into the freeze cycle my pressures were ranging from 300-310 high and 41-45 low. The machined limped out a freeze cycle in 50 minutes.

I'm wondering if anybody can give me some tips about checking txv's, hot gas valves, and water solenoids for leaks. I'm also thinking the condenser coil could have been a little cleaner. Does anybody have any tips for cleaning a condenser coil without spraying dust over everything? If I spray it with water the water will leak everywhere and the coil housing is so tight I doubt a shop vac could reach everything.

[darkbeekeeper]

Its hot the water temp is warm ambient air is warm and with the 3 beeps your running close to the freeze timer 2 loads of ice hits a 60 min cycles it will trip, biggest problems with km's is they need to be clean and they need the proper water volume to meet the fill and flush timer and they like to leak water by the water valve when its in freeze mode check the drain to make sure water isnt leaking by the water valve warm water = longer freeze times low ice production

[darkbeekeeper]

here is a good read there is some good info how to do quick check ect

http://www.hoshizakiamerica.com/manu..._H(3)_serv.pdf

[itsiceman]

If you use a wet towel on either side of the condenser it will catch most of the dust if you have to blow it out still.

[BURL-REF]

I always wet the condensor before blowing it out

[2sac]

If you use a wet towel on either side of the condenser it will catch most of the dust if you have to blow it out still.

If it's in a kitchen, just take a hose to it. Bin's probably empty anyway. You may even have to pull the motor and hit the coil with degreaser.

[Dchappa21]

If you use a wet towel on either side of the condenser it will catch most of the dust if you have to blow it out still.

This is what I do.. Old sheets cut up works good too.

[skrewdriver]

thanks for the tips, I'll try that next time.

[worrut]

I alway take the side pad out and take a fan blade out and spray with nu-clan the blue one without mix with the water , and clean out with a hot water and blow with co2 .I know it will take forever but if you work in the Chinese or any Asian food you will know what I am I taking about ,good luck

[itsiceman]

thanks for the tips, I'll try that next time.

Your pressures seem spot on from what the book says. Going out to 50 min in freeze might be something other than the condenser coil

[itsamine]

After it fills with water close the isolation valve for the water inlet(before the solenoid valve) and see what happens. It might be leaking by. When you unplugged the FS did it go into harvest? I do not think your hot gas valve is the problem. So a few things left to check. The LL drier or the solenoid valve are they frosting/sweating? The water valve(see above). The expansion valve? Is the inlet of the evap have frost on it then it goes away?

[icexprt]

Is the water distribution system clean? Make sure evey row of every evap. is getting water flow to make cubes.....Hoshizaki brings in "X" amount of water (enough for one batch of ice) at the beginning of the cycle and when the float switch tells the control board the water water level has dropped to "Y" level, the board sends the machine into harvest. Therefore, if extra water enters the sump during the cycle, you get long cycles....or, if let's say 6 rows of evap. surface don't make cubes because the water distribution tubes are clogged, then the rows that did get water and made cubes will have to make much larger cubes to deplete the water that should have been made into cubes on the missing rows. You are not going to enter harvest until that water level gets to a certain point. The cycle time will be extended in this scenario due to the ice cube on the evap actually acts as an insulator between the evap and the water you are trying to freeze.
On another note, we have seen a fair number of aging control boards cause a 3 beep error code the last couple of years. You have to really get lucky to catch the problem when it occurs, but what we've been seeing is the board will intermittantly drop power to certain loads during the freeze cycle....usually the water pump or the contactor, either of which will give you your 3 beeps if they stay de-energized long enough. What we have started doing with some of these, is changing out the board and waiting to see if the problem recurs. Usually we'll establish a pattern as to how frequently it is happening first, and then change the board and give it "X" amount of time and if it doesn't act up within that time we'll write a bill and consider it done. I hate a "parts changing" mentality towards diagnosing but sometimes you have to do what you have to do!

[VAV616]

Id agree you could probably use a good evaporator cleaning.
aside from just running the chemical(hoshi is Stainless Steel) through the clean cycle for 45 min or so you should also unhook the rubber tubes from the top rails, and slide those white plastic header pieces out to clean them, then take the top off and get the hose and spray down the evaporator tracks.
of course you have to take out all the ice to do this.
even with a 90 degree ambient you should not have more than a 40 min freeze time, more like 35 at 80 degrees.

http://www.hoshizakiamerica.com/tech...R404Aguide.pdf
p.97 has the spec chart for your km1300 air cooled.

for the most part you can verify the hot gas valve (or cool vapor valve if your picky) is not stuck open just by taking the temp on either side of it, if its hot on both sides, its leaking past. and you can still measure the superheat just like an airconditioner, and the txv ought to be holding it around 10-15 degrees. if you see that then your valve is OK.

likewise it also has a liquid line solenoid valve which could be partially stuck maybe, check temp on either side, if there is no TD then its ok.

I'd do the full cleaning of the evaporator water circuit before id go tearing into the sealed system.

[chamberlain]

hello skrewdriver spent 30 years in az still hold my phx lic there know in oh ,i hit those coils evap coil cleaner few cans also spray water bottles in those tuff location hey tailler freezer sales and service co i still talk to roy the service manager from time totime there good help there the hoshi rep.the best ice machne out ther .i apeace of work ice o matic kick me .bad txv then bad psi switch then weak compressor only 7 y. putting in new one i bid hoshi stupped wont to go back to same nightmare' i miss az .also rses hold education meeting out there say hi to parry anderson for me he is chapter president . also tailer freezer hold realy good shools on hoshi bring your stomech threy will feed you;stay cool .

[joemach]

Clean-Clean-Clean and make sure full water flow over the evap coils.

Hoshizaki uses water volume used to determine harvest, so make sure all distributor tubes are clear and even the little cups that the water runs into from the distributor tubes.

In the future, first thing to do when you meet an ice machine - Clean it! And clean it good! Do not listen to anyone else's diagnosis. Similar to HVAC work, you really can't do subcool or superheat until you verify airflow. So the guy that tells you it must be low on gas because the suction is so low, the first thing you do is check airflow.

So the first thing on ice machines is check water flow.