Boiler Efficiency vs Reliability

mech_2

Cardew wrote: »

This is more Mech's field of expertise from what I gather from his contributions.

I should probably make it clear that I'm just a keen layman. I'm not a heating engineer or physicist - I studied electrical engineering. I've just become a bit geeky on the subject of heating in the last couple of years. I base whatever opinions I make on here on what I've either read online, or observed in my own/my family's/friends' houses. I would welcome corrections from more knowledgeable people - it helps me learn new things.

mech_2

amtrakuk wrote: »

Where did the sludge come from? Occasionally I used to top the central heating circuit.

I live in Leeds and can't really say I have got hard water, I do get red stains wound the plug hole.

I don't think I can really comment on what happened to your boiler without having been there to see it.

The inky black sludge is iron oxide and it comes from gradual corrosion of the radiators. I have some of that in mine too, it's common in old systems. The water in the radiators should have a chemical inhibitor added to it to prevent this happening, but I gather this doesn't keep working forever. Given that my pipework is old (20 years+) and my boiler is fairly new (3 years) and I have microbore pipes, I expect to see blocked pipes before it causes a problem inside my boiler.

amtrakuk

mech wrote: »

I don't think I can really comment on what happened to your boiler without having been there to see it.

The inky black sludge is iron oxide and it comes from gradual corrosion of the radiators. I have some of that in mine too, it's common in old systems. The water in the radiators should have a chemical inhibitor added to it to prevent this happening, but I gather this doesn't keep working forever. Given that my pipework is old (20 years+) and my boiler is fairly new (3 years) and I have microbore pipes, I expect to see blocked pipes before it causes a problem inside my boiler.

I guess thats what happened. I presume it was put in when I first got the house. It involved a greenhouse pressure pump/spray affair and I think I paid about £50 for it was a few years now.