My scotman model sce170a1a.goes into harvest to

Have a look at the side of the evaporator; there is a probe (thermistor) attached to it that tells the control board when to initiate the harvest cycle. make sure it's clean and attached properly and doesn't need replacing. If hitting the float switch initiates the harvest cycle it sounds like you have a blocked/ scaled water tube or switch housing. take off the bottom of the switch assembly (black rubber bit) and clean through to the water chamber. run a cycle of descaler before trying again.

Flush water through the filter, & adjust the depth setting for the ice on the harvest tray.

The ice machine has a HARVEST TIMER. You can adjust the harvest time, it comes from the factory for 3 minutes. You should not have to adjust it 3 minutes is plenty of time if every thing is working right. If the machine is operating making ice but not falling in storage bin then check these possible cause.
1. ICE may be stuck in the evaporator and the unit is " frozen up "
POSSIBLE SOLUTION: Clean and sanitize.
Possible Cause: Harvest time set too short - timer needs adjustment.
2. Harvest timer bad: replace harvest timer.

Is the machine producing ice thick enough to come off the evaporator plate? the machine will try to harvest 3 times before it locks out on long harvest. Harvest cycle: The compressor and hot gas valve are both powered during the harvest cycle. The fan and pump are off at this time. The machine stays in the harvest cycle until the evaporator thermistor senses 52 DEG F. If the bin is not full, the unit goes into another freeze cycle. I would check the Thermistor

This could be several things. This means it has tried to harvest the ice 3 consecutive times before the machine has locked out.
1. Likely Cause, Ice bridge thickness too small, not enough ice to open curtain. PROBABLE SOLUTION, Check and adjust if needed.
2. LIKELY CAUSE, ice bridge too large, ice frozen to evaporator frame. PROBABLE SOLUTION, Check and adjust if needed.
3. LIKELY CAUSE, Purge valve does not open, water melts ice bridge, not enough ice to open curtain. PROBABLE SOLUTION, Check purge valve during harvest.
4. LIKELY CAUSE, incomplete ice formation. PROBABLE SOLUTION, Check water distributor for partially plugged holes. The machine needs to be cleaned and sanitized every 6 months.
5. LIKELY CAUSE, Curtain out of position. PROBABLE SOLUTION, check curtain for swing restriction.
6. LIKELY CAUSE, Curtain switch dose not open when curtain does. PROBABLE SOLUTION, Check switch with ohmmeter if bad replace.
7. LIKELY CAUSE. Machine in very cold ambient. PROBABLE SOLUTION. Move machine to a warmer location.
8. LIKELY CAUSE. Hot gas valve does not open during harvest. PROBABLE SOLUTION. Check hot gas valve with a volt meter during harvest mode to see if you are getting correct voltage to it. If not then replace control board . IF yes and valve is not opening then replace valve.
9. LIKELY CAUSE. Harvest assist probe out of position - ejector pin not retracted. PROBABLE SOLUTION. Check harvest assist mechanism - spring should retract pin.
10. LIKELY CAUSE. Damaged evaporator. PROBABLE SOLUTION. Check evaporator surface. Make sure the plates where they intercept each other is not loose this will cause ice to hang up. check to make sure the nickel is not peeling off, if so then the plate will need to be replaced.
11. LIKELY CAUSE. Fan motor stays on during harvest. PROBABLE SOLUTION. Check controller using test mode. If this dose not help you then give me the model number so i know what machine you have.

h=harvest 2=harvest problem 8=makes ice to fast 0=off.most common issue is your senors/ice mach needs to be descaled and clean

So is the unit going into a harvest and not going back to a freeze cycle? dose it dump a batch of ice but wont go back into a freeze cycle? before you reset it have you pulled the front cover to see what code it is giving? any time you have to reset it that means it locked its self out on a fault. if unit freezes and go's into a harvest and dumps the ice but dose not go back into freeze cycle check the door switch when the ice dumps the deflector door opens a magnetic switch which tells the board the harvest has finished and then the freeze cycle begins. Now if there is no ice falling off the plate to open the door then the board will time out and try 3 more times to make ice before it locks it out. the same go's for the harvest.

First it has to go through freeze cycle then harvest cycle to drop ice then back to freeze cycle. If you have never worked on ice machines before you should call a service company.

You have a problem with float valve. See page # 8

http://www.scotsman-ice.com/docs/uploaded/sct/manual/SCE17MAN.pdf

How long is a freeze cycle on your unit? How big are the cubes that it's dropping? The three beep error indicates that the unit exceeded maximum freeze time.