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dingaling
24-02-2017, 07:04 AM
Wow. I posted on here years ago and the site seems to have got very technical. Good job.

I posted about problem AGA Freezers, LA245-R2 model. Manufactured by Williams and totally useless. But I have had mine for 10 years and plod along with occasional complete defrosts to de-ice the chiller.

So the original post and saga is here:
http://www.refrigeration-engineer.com/forums/showthread.php?24448-AGA-Freezer-Problem-and-Codes-needed&

I get about 1 request every month or so for the firmware codes, even though they are on the above thread, so I assume some get them there.

As the thread is closed, and this is where technical docs are supposed to live, I am adding an update here. The site doesn't allow decent sized file attachments though.

The chiller/condensor/compressor in these units is under rated. But the main issue is the design of the drain-off of defrosted water from the chiller. It is supposed to drip off the chiller onto a tray and then out of a drain hole at the back to a rear reservoir to evaporate. But the tray is too horizontal and the water does not drain away before freezing up there and then blocking the next defrost cycle and so on.

The AGA/Williams fix is to add a heating mat to the underside of the tray which activates with each defrost, to keep the defrost water liquid. But this is not always enough. You cannot really get to the rear drain hole to check that is clear.

The configuration that now works for me is:
Turn off the regular auto-defrost cycle (DF=0)
Set the temp a bit higher to -17 instead of -19.
Increase the tolerance to -2C or -3C to allow more rest time.
Keep the freezer door closed as much as possible!!!
Do occasional manual defrosts (with the DF button), a couple in a row.
Do a full freezer defrost when needed - about once a year. Sometimes twice.

You know when it is needed because the chiller fails to lower the temperature below about -8C. This means it is iced up. The circulating fan at the rear may also be blocked by ice if it is too bad, which just exacerbates the lack of cooling capability, and the only solution then is a full defrost, with the associated puddles of water and inconvenience.

Here are the control panel specs again.

Please respond with any further insights or stories.


14631

-jd