Hot metal/burning smell from combi boiler

[J0313]

Have some problems with my boiler that cant seem to get fixed. It's a worcester bosch greenstar cdi 30 combi and it's about 5/6 year old I think.

So basically the boiler has been making like a burning/hot metal smell. But it seems to only make the smell when the boiler has been like working hard when it cuts in the morning and in the evening when the thermostat gets it to cut in, it takes it's time for the smell to come about, it doesnt just happen as soon as the boiler fires up. The heating and hot water has been working fine and I have a CO alarm at the boiler and that's never went off either

Had gas engineer out to look at it and he done the flue gas check and that all looked ok but when he came the boiler hadn't been running long so the smell hadnt built up yet and he said everything seemed fine to him.

Any help greatly appreciated. Incidentally I wont be touching anything, it's just so I can try provide a steer to the next guy I get round.

 

[Chuck]

Have some problems with my boiler that cant seem to get fixed. It's a worcester bosch greenstar cdi 30 combi and it's about 5/6 year old I think.

At that age the boiler may still be undertake manufacturer's warranty.

Are you sure the smell is coming from the boiler? A burning / hot metal smell is often an electrical issue, something like a bad connection arcing and/or overheating. This could be something inside the boiler but could also be something external to the boiler. If your house wiring hasn't been tested relatively recently, it might be a good time to get a sparks in to do a 'ten year check'. Ask them to to pay particular attention to the supply, fusing and earthing associated with the boiler.

 

[centralheatking]

Burning Hot metal smell is how I would describe faulty electrical connection, electrical overload
Centralheatking

 

[J0313]

Thanks for the steer gents, I removed the outer casing to have a quick look over the electrical wiring to see if I could see anything visually damaged.

There is black scorch marks around the inside.

I noticed a bit of that outer casing foam insulation has melted and it looks like 2 red wires (having looked at the manual these are the ignition electrode and flame sense electrode) that go into the top of the heat exchanger seem to be fouling against the inside of the casing because their plastic sheaf is protruding out too much which I guess might be causing the smell. These wires felt quite hot to touch, would that be normal?

Any ideas on the way forward?

 

[ShaunCorbs]

Pic of said wires please don’t use the boiler yet if you can I think I know what’s happened

 

[centralheatking]

Thanks for the steer gents, I removed the outer casing to have a quick look over the electrical wiring to see if I could see anything visually damaged.

There is black scorch marks around the inside.

I noticed a bit of that outer casing foam insulation has melted and it looks like 2 red wires (having looked at the manual these are the ignition electrode and flame sense electrode) that go into the top of the heat exchanger seem to be fouling against the inside of the casing because their plastic sheaf is protruding out too much which I guess might be causing the smell. These wires felt quite hot to touch, would that be normal?

Any ideas on the way forward?

Turn it off at the fused spur..the one with the red light and or the fuse..leave it off and call out a good gsr engineer do not be tempted to use. Centralheatking

 

[J0313]

Pic of said wires please don’t use the boiler yet if you can I think I know what’s happened

Boiler switched off, I wont be touching anything. Calling engineer in the morning.

Attached is pics of where the ignitor wire connectors are fouling on the casing insulation.

 

[ShaunCorbs]

good youve got the updated probes (the part that the wires go into) that was my idea out the window

 

[Antiqmark]

Turn it off at the fused spur..the one with the red light and or the fuse..leave it off and call out a good gsr engineer do not be tempted to use. Centralheatking

I have the same problem as the person to whom you replied. I cannot use boiler for longer time because metallic smell starts to be present in the kitchen , probably from the cellar. I reported it to housing association but they ignore me already for 3 years so I do not use boiler at all. Nobody knows what is going on and when I claimed it to installer a technician came and said he does not smell anything. Do you have a company so that I could contact you over the phone ? I can pay you for a check
Jan, Edinburgh