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Old 10-23-11, 08:10 AM   #29
Xringer
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Default 7:00 AM test?

At 7:00 AM on a Sunday morning, the last thing I wanted to hear was a TED alarm beeping.
But, it was almost time to get up anyways.

I figured it was another over-voltage alarm, but it wasn't. It was a max power alarm.

Now that I'm using the TED to monitor dual Sanyo ASHPs,
I should have re-programmed the TED's max KW alarm a little higher..Like 4KW maybe?

Last night, I set the timer on Sanyo #2, for 6:50AM so the den would be
nice and toasty when we got up. (Sanyo #1 was on overnight at 19C).
It worked very well before, when it was not so cool outdoors.
This morning, it was down to 35F (@99%H & 34F DP) outdoors.

There was a little frost on the deck, and water under the outdoor units.
I'm not sure, but the Sanyo #2 may have been in a defrost cycle when the TED alarm sounded.

Anyways, I turned down Sanyo #1 (main house) and did some testing on Sanyo #2.
Not so tolerant anymore. It will exceed 2.4kW if more than 2 deg C of change is requested.
Of course, it did some self-Re-sets* (auto-breaker is working fine),
making me understand that 35F means the Sanyo #2 has to be carefully
adjusted, one deg at a time, to avoid big power use surges.

*Note:
A couple of the auto-breaker resets were very clean full resets, with the system
re-starting again at low wattage, as if there was a grid failure.
But, a couple of other auto-breaker resets were just a system stall.
A 1/2 second hesitation in IDU fan speed before recovering.
I think this type of Stall & Recovery is probably not good for the compressor.
I'll need to think about hacking the Transistor switch, so full resets always occur.



I did a comparison between both units. When operating at the same
indoor room temp, IDU coil temp and fan speed, they both used about the same amount of power.
So, at least in this temperature range (mid 30s F) the new install seems
to working about the same as the old unit..

I plan to perform this same comparison when it gets down to the 20s F.
That might be when we might add another 1/2 pound of R410A to #2.

Cheers,
Rich

Last edited by Xringer; 10-23-11 at 08:27 AM.. Reason: *note added
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