hoshizaki freezing up

[anthonyac1]

I went on a service call, found hoshizaki ice machine was frozen. one key thing is there are 2 evap coils. only the right one was frozen solid. the left one had no ice at all. so I defrost with hot water hose. I then removed the black rubber hose from the water inlet valve it was not leaking through. I put it back to together then stated machine shut it down and rechecked the water inlet valve again for any leakage nope. the water inlet pressure seemed week. the inlet screen was clogged I cleaned it out and put it all back together. started the machine unit makes full ice in 34 mins within specs. I monitor it through the harvest factory set for 1 minute. the left evap removes the ice fine but the right evap coil still has cubes once the freeze cycle starts they eventuall y fall off but im sure after a while some gets stuck. I changed the harvest time for 2 minutes it helped out but that's a band aid over the issue.
M# km-1301sah S#B05036c.
I did not check the refrigerant pressures I figured to rule that out in a way it seems both evaps would be affected, also once the ice machine was off and the evap was able to dry I can see a film on the evap coil. but both were the same pretty much so im kind of ruling that out, its night and day the left evap is totally free of ice, but the right one still has ice. has anyone ran into a similar issue??? also the float switch was adjusted as low as possible. I raised it a bit to reduce the cube size if im correct.

[trippintl0]

Have you confirmed the right evaporator is not separated?

[coolingitrite]

I agree sounds like may have separation on that evap. ice did not drop properly during harvest and built up. seen them with waves in it if you look down or evap moves if you grab a grid and tug on it

[anthonyac1]

Nope! I didn't check that. I figured since its making good cubes it must be in tack. Or am I wrong?? This machine is fairly new. It's about 1 year old

[coolingitrite]

could make a good cube but not harvest properly

[coolingitrite]

I would think this would cause problem on both sides, but, did you check to ensure that bin stat is opening when ice hits it and shuts the unit down so ice does not back up into evap

[coolingitrite]

also raising the float will make it smaller but may also affect how the ice falls. I mean with the cubes weighing less..

[anthonyac1]

That makes sense. Smaller cubes weighs less so it can hang on better than a heavy cube.

[kklobas]

CLEAN the machine!
The film is mineral deposits. Clean it

[MicahWes]

What do you mean that the harvest was factory set to 1 minute? Hoshi harvest is terminated by evaporator temperature, not time. I have never seen a Hoshi that only harvested for 1 minute. Also, a water valve leaking through will cause long freezes, not harvest problems. Insufficient inlet water flow during harvest will greatly extend time though. You need to figure out why your harvest cycles are so short, make sure the plate isn't separated (though if it is forming ice fine, it should harvest fine), and maybe make sure the harvest pressures are high enough. If harvest pressure is low you could have a hot gas valve problem, though it would be pretty unusual.

[anthonyac1]

I put ice on the bin control and it did turn off. That working properly. Also if it was the bin control both Vespa should have been effected by it. It's not like one evap had more ice than the other... The right evap was frozen solid while the left one had no ice at all. I triple checked and told myself dam I never seen this before. Usually they both freeze up

[2sac]

Clean the machine and verify proper water pressure first and foremost. The hot gas enters the right evap first. It's odd that the ice doesn't drop. If the inlet screen was plugged, I'm willing to bet the distribution tubes are plugged as well.

[kklobas]

That is time after suction hits 48 degrees. U can set all the way to 3 minutes. Water flow is crucial. Clean the damn machine. Harvest distribution tubes, main water dist. Tubes, evap plates, check valve, etc.... It uses a completion timer after suction hits temp. Number one cause of freeze up is dirty machine

[anthonyac1]

The thing with cleaning the machine. 1 its pretty clean yes it does have a light film on the evaps. If doesn't make sense for the right one to be freezing up and not the left. Atleast the left should have some ice build up. But then again it could be the issue.

[anthonyac1]

That's what I hear is the main issue. Ill go ahead and tell them to clean it. I've seen about a few machines and this is by far the cleanest one Ive ever opened. And the others work good still dirty.

[anthonyac1]

The distribution tubes on this machine are all clean. The distributors are all clear.

[2sac]

Is the water pressure above 25psi? Hopefully way above?

[coolingitrite]

That is time after suction hits 48 degrees. U can set all the way to 3 minutes. Water flow is crucial. Clean the damn machine. Harvest distribution tubes, main water dist. Tubes, evap plates, check valve, etc.... It uses a completion timer after suction hits temp. Number one cause of freeze up is dirty machine

good advice. clean machine. don't know bout florida but back in san Antonio tx, lots of calcium....... cleaning (descaling) twice a year

[mizzterclean]

Have you checkef to see if you have restriction at the strainer for the right hot gas circuit

[bob1420]

you need to put guages on to see press