ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Top Posters(30 Days)
twh 3
Recent Posts
FPE in Germany
by Texas_Ranger. 11/19/17 07:30 AM
Ceiling fan distance from outdoor hot tub
by gfretwell. 11/16/17 02:18 AM
diazed fuses
by Texas_Ranger. 11/13/17 03:02 PM
Theft deterrent alarm
by gfretwell. 11/12/17 01:39 PM
EEPROM errors on XC7Z010-2CLG225I chip
by twh. 11/07/17 05:45 PM
New in the Gallery:
Gallery Test
Popular Topics(Views)
242,579 Are you busy
178,748 Re: Forum
170,022 Need opinion
Who's Online Now
0 registered members (), 30 guests, and 6 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate This Thread
#195250 - 07/21/10 11:59 PM Trouble Call  
BigB  Offline
Joined: Mar 2004
Posts: 719
Tucson, AZ USA
I have a trouble call coming up and not sure what to look for. The customer says he had a new air cond system installed, a split system with a variable speed indoor blower unit. Now every time the unit starts, his flatscreen TV goes nuts with buzzing and lines on the picture. It didn't happen before the new AC was installed. The TV is NOT on the same circuit as the AC. The AC people came out and checked everything and said there is nothing wrong with their installation. The new AC replaced an old one that was in the same place, on the same circuit, and didn't cause any interference on the TV.
I can't think of anything except putting each on opposite legs of the service, if not already done, or installing a filter on the TV. (The TV is built in so he has not tried other circuits using an extension cord.)

What else can I look for, or will it be a total waste of time?

Work Gear for Electricians and the Trades

#195251 - 07/22/10 01:12 AM Re: Trouble Call [Re: BigB]  
JoeTestingEngr  Offline
Joined: Nov 2005
Posts: 791
Chicago, Il.
I bet the fan on the new AC has a VFD controlling it. We know how much noise they can generate. I think it would be better to place any filtering as close to the noise source as possible, especially since they will probably discover more things that it interferes with.

#195252 - 07/22/10 02:41 AM Re: Trouble Call [Re: JoeTestingEngr]  
gfretwell  Offline

Joined: Jul 2004
Posts: 9,135
I second Joe's opinion. You may be able to do the HVAC guy's job by getting the model info from the air handler and beating up Google a little. There may be a known problem and a fix from the manufacturer. It is probably as simple as a noise filter kit.

I am guessing they use an antenna, not cable?

If it is cable/satellite, those guys may have something too.

It could be as simple as an unterminated TV cable somewhere.

Greg Fretwell

#195254 - 07/22/10 07:54 AM Re: Trouble Call [Re: gfretwell]  
renosteinke  Offline
Cat Servant
Joined: Jan 2005
Posts: 5,316
Blue Collar Country
And, lest we forget, GROUNDING. Make sure the AC has a good bond, from the unit all the way to the service.

#195260 - 07/22/10 03:27 PM Re: Trouble Call [Re: renosteinke]  
twh  Offline
Joined: Mar 2004
Posts: 922
Regina, Sask.
It could be as simple as an unterminated TV cable somewhere.
... or a loose co-ax connection.

#195266 - 07/22/10 10:07 PM Re: Trouble Call [Re: twh]  
BigB  Offline
Joined: Mar 2004
Posts: 719
Tucson, AZ USA
Thanks guys, turns out the guy called this morning and said he figured it out, he ran an isolated ground to the sattelite dish. I didn't think anyone was still using motorized dishes??

#195268 - 07/22/10 10:27 PM Re: Trouble Call [Re: BigB]  
renosteinke  Offline
Cat Servant
Joined: Jan 2005
Posts: 5,316
Blue Collar Country

I don't believe it for a second.

What I DO believe is that he mucked something up during his DIY installation, then somehow got his errors to cancel out as be blundered about 'fixing' it.

When - not 'if' - you get called back, CYA. I wouldn't be surprised to find 10 amps running through that 'ground.'

Member Spotlight
Levittown, PA
Posts: 810
Joined: April 2004
Show All Member Profiles 

2017 Master Electrician Exam Preparation Combos
2017 NEC Electrician
Exam Prep Combos:
Master / Journeyman


Shout Box
Powered by UBB.threads™ PHP Forum Software 7.6.0
Page Time: 0.017s Queries: 15 (0.003s) Memory: 0.7855 MB (Peak: 0.9425 MB) Zlib enabled. Server Time: 2017-11-19 21:35:56 UTC