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sger9
18-06-2009, 02:59 PM
Hi All. I am looking for help with an r404a charged ice machine. Replaced comp due to faulty valves (and drier). Pulled down to 200 micron vac and it held for 1hr. Weighed in charge of 340g and tested. (normal cycle time should be about 18-20 mins) Cycle is taking 30 mins approx. Checked subcooling and got 9 degrees c. Superheat is running at 24 degrees c. DT on condensor (air on=15c air off = 21c) is 6c. Head pressure is kept between 180 &210 psi and suction press is running between 20 and 25 psi. Anyone got any ideas what could be wrong cos this thing is wrecking my head.:confused:

MrC
19-06-2009, 07:47 PM
So the problem is its taking a bit longer than expected to make a batch of ice?
Does the complete evap ice up?
Whats the temp of the discharge and liquid line?
How is the harvest controlled on these machines?
MrC

icecube51
21-06-2009, 11:30 AM
i think the super heat is to mutch and subcool to low. was the 340gr the original ore the recuperated amount.

Ice

Yuri B.
21-06-2009, 11:50 AM
Hello Sger9.
By the way, you did not mentioned whether you had done pressure test after the repair ?

sger9
22-06-2009, 11:27 AM
Sorry about the delay replying. Problem sorted, or rather multiple small probs. Conds fan was heavily gummed up so running slow and not efficiently, cap pipe was too far in to the drier(had set it up properly but obviously moved during brazing). Just small probs but added together, along with the hot weather all added up to a longer than normal cycle. Also, as embarassing as that was, the biggest prob was the fact that I was fixing it at home. No water in the shed so I ran a hose to the shed as I usually do.(what can I say, I have been busy since the shed went up and havnt had time to finish it) Never noticed that the water in the hose was coming in to the machine at about 35degrees C due to the fact that the concrete yard was heating the hose. Thanks guys for the responses but sorry for wasting your time. S.