Radio interference from my central heating

[alifrank1]

For the past few years, I have been getting intermittent interference on my TV and radio. I discovered last week that it was the central heating! (each time it happened, I turned the heating swith off and it stopped)! My central heating system is very old but boiler only a couple of years old.

I have a contract with British Gas and a guy came and said "I might be right, but might not", so a few days later another guy came and fitted a new timer control. (the part he used just plugged and unplugged - no wiring needed). I told him I thought it needed a suppressor (I'd read that on the net), but he said what he did would do the trick

Anyhow, the interference is still happening. I need to call British Gas back and get someone else in to look at it, but has anyone got any ideas what I should say to them this time? The fitter that came was a real 'know-it-all' and although I am quite handy, I am still a mere woman!!

 

[chrishutt]

Just keep calling BG back. With a bit of luck you'll get a new component fitted every visit until you end up with virtually a brand new CH system. Putting up with obnoxious know-it-alls for the odd hour is a small price to pay (remember they have to live with themselves 24/7!).

 

[cross thread]

is it a baxi boiler? suppressor often fails .

 

[alifrank1]

Hi gordon, just looked and it's a Potterton Kingfisher. The boiler is in an outhouse but the control timer is upstairs in the airing cupboard. It's the timer I have turned to prove that it's the central heating that is affecting my tv and radio.

 

[Agile]

Most interference cases are caused by an inadequate antenna system for the TV and radio.

Do you really have a proper outdoor roof mounted TV antenna with at least 13 elements? That within the service area should give about 2 mV at the TV and give you a good picture.

I assume that at least you are listening to your radio on FM ? Even so you should be using an external antenna.

You should get interference free reception if you get a DAB radio and a Freeview digital box for your TV.

Tony Glazier

 

[chrishutt]

I had a case recently where a ham radio operator experimenting with a stronger than normal signal managed to trigger a lock out on his C&M Britony Combi 80SE boiler. The aerial was strung horizontally down the garden, less than 4 metres from the boiler at its nearest point. If the signal coincided with an ignition attempt in the boiler it went to lock out.

 

[Slugbabydotcom]

I told him I thought it needed a suppressor

I am inclined to agree as this should reduce the spurious emissions which are probably coming from your gas valve.
In the meantime invest in some ferrite rings. You should be able to get these cheaply from a tv repair shop.
Take the plugs off your TV and radio power leads and thread each cable through the ring about 5 times. Do the same to the aerial lead except you shouldnt need to take the plug off. This will stop the RF getting in to your wires.
Another tip is to use a surge protector on your tv and radio as you would for a computer. This would stop a spike getting through via the power supply.
Its a long time since I did a radio ham course and I have forgotten most of it as I kinda proved on a recent post. So it would be best to post this on a ham or TV repair forum

 

[DP]

I would be inclined to look at the thermostat (on the boiler) or the gas valve.