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Hi All,
Can anyone recommend a RFI safe inverter airconditioner system?
Im thinking of having a 7kW system installed and wonder if anyone has found
a brand that is RF quiet ; most importantly on 6 meters.
Thanks in advance for any observations
Posts: 291
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Joined: Sep 2016
We have a Fujitsu AOT30L outside unit feeding 4 inside blowers, and it generates S9+ noise across HF.
I tracked the source to wiring from a PCB to the motor, and fitted a string of ferrites to that cable. That cut the noise down to S7. I have been meaning to make up a substitute wiring lead that has a RF choke inline but haven't got around to it
The outside unit is at the other end of the house from the HF antenna and I did that deliberately, anticipating it may be a noise-generating issue.
All this said, when I researched units prior to buying someone told me their Fujitsu single outside unit feeding one blower did not generate noise.
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Thanks for your response Damien.
That is exactly the sort of information I need.
Speaking to sales reps they just give me a strange look
when I bring up RFI .
Chris.
Posts: 291
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Joined: Sep 2016
My installation company (a large one that works over the state) were very good. They got me to detail the issue and I included spectrum analyzer shots of the unit off and on.
Suffice to say they got nowhere with the brand head office, and referred the issue to Japan. The latter said words to the effect that trying to receive broadcast stations outside their broadcast area was problematic (even though my report was specific about the 2-20MHz range) and to check the house earth wiring (which was subsequently checked and fine).
The only issue the local company was aware of was potential TV interference if any brand's outside unit was placed below or in the vicinity of an external TV antenna, so they would always make customers aware of that when discussing a potential location. The fact that they work in regional areas where TV signals may come from sites some distance away may be an issue rather than in metro areas.
