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Old 01-07-10, 05:29 PM   #126
Xringer
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Default R-410A leaked

The pressure during cooling was a little too low. Should have been between 115 and 125 PSI.
The Sanyo kept working okay during the Xmas holidays,
but may have been using a little too much power as the days got colder and colder.

On the very cold night of Dec 29, it stopped heating. The fans were working,
everything seemed normal, but there was no warm R-410A flowing in the copper.

This week, under the guidance of Sanyo tech support, I tested the unit and found the R-410A had escaped.



There are tracks where lube ran across the top of the insulating disc on top of the compressor.

This copper tube is a thermistor mount, located just above the compressor. It is brazed on the right side.
There is fresh lube on the nylon cable tie and the steel sensor clip.


Using nitrogen at 300 PSI, I was able to locate the general location of the leak in a copper tube.

I held a plastic tube to one ear and moved the other end of the plastic tube
around, inside near the tubing, until I heard a loud hiss coming from thermistor tube.
I was able to hold the sound-tube near the telephone mic, so the Sanyo tech could hear it too.

The overall quality of the materials and workmanship is impressive.
My guess is, the brazing on the right side of the sensor tube,
hit a copper tube defect, or got so hot, it melted a tiny void in the copper.?.
I was not able to 'see' the actual hole, I suspect that it's very very small.


After about an hour, the pressure didn't seem to be dropping at all.
It was still almost 300 PSI. I had to slowly bleed the nitrogen down.

Sanyo has started the paperwork to get a replacement unit shipped,
but I have idea when that will happen. This model is often out-of-stock.

Now, I'm wondering about how to clean out the line-set & indoor unit coil,
before installing the replacement outdoor unit..
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