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Gideon
 
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MLD,

My impression is that you expect the installer to eliminate any unreasonable
RF that the equipment is producing, and that you are seeking advice and
experimenting to aid the HVAC company in finding & fixing the problem.
I agree - in your situation I'd do the same.

Also, I agree with you about the cable drops. We've got 5 TVs connected to
cable, but we've also got a few that aren't. I don't want those on cable for a
variety of reasons - too much splitting of the cable signal, difficult cable
runs, appearance, etc. Even if extra cable drops would fix the problem,
I'd still want the furnace not generating all that RF.

Suggestions:

1) Just as a sanity check, use a portable battery operated radio to see how
much noise it picks up from the furnace. From what you have said, I'd expect
that it would also have a problem. But you want to confirm that the
interference is coming through the air and not through the house wiring.

2) Experiment with the shielded harness. Seems to me that you could use some
aluminum foil to carefully extend the shielding another 6 inches. If that
helps substantially, then get the HVAC folks to do it correctly. I'd also want
to know why the harness is generating so much RF in the first place.

Good luck,
Gideon

======================

MLD wrote in message ...
Have a new High Efficiency Trane Gas Furnace. Every time it fires up the
picture on a TV set (rabbit ears antenna) on the floor right above it goes
haywire. The picture becomes almost unwatchable because of all the noise
streaks and snow in it. The source of the problem is the Vent Blower
(Inducer motor)--the electrical noise is only present when it runs.
So far, following Trane's service Tech instructions, the HVAC Co techs have
done the following:
1. Checked to make sure that there is a good ground between the furnace and
the earth ground.
2. Replace the wiring harness to the vent blower with a shielded
harness--Trane may call it a shielded harness but the shielding ends about 6
inches from the motor. So there is 6 inches of unshielded wiring which to me
is like not having any shielding at all.
3. Replaced the control board.
Why they haven't suggested replacing the Vent Blower is a mystery to me.
However, while there has been quite a bit of improvement the TV noise
problem still exists. Now waiting on the results of a discussion between
HVAC Co.and Trane.
I've been told that I'm not the only one that has experienced this problem.
Has anyone else seen something like this?
MLD