Strange dimple has appeared on radiator

[PChris]

Hi, the most bizarre thing has happened to a newly installed (1 month) radiator.
Plumber came round and installed the radiator in the kitchen and a week ago as I was passing the said radiator, I noticed a sort of raised round 'blob' at the very top of the radiator. It was about the size of a penny, but actually bulging out. When I touched it it was hard metal (like the radiator) and there was no break in the surface of the rad - i.e. the paint work was smooth.
I assumed the blob was always there and we hadn't noticed it and I was a bit annoyed about this as its right at the top. Anyway yesterday I noticed that it had GROWN!!! How is this possible?!! It's now double the size, but still no break in the surface - it's totally smooth, but I'm really concerned now!!
We have switched the radiator off, as my son has said there must be some sort of pressure build up inside - is this possible?? I'm not worried about the shop replacing it but I would like to know what this is - never heard or seen anything like it - would be great if someone could help - thanks

 

[Dan Robinson]

Pictures please.

 

[PChris]

 

[stardanny]

Pinhole leak, surface paint keeping water in. Radiator is faulty, take it back to shop.

Daniel.

 

[DaveHerns]

Could just be the paint bubbling up but then it wouldn't be "hard" . Doesn't look like rust from inside . Don't pop the bubble without some buckets and rags nearby just in case....

 

[Agile]

Why did you replace the previous rad?

What chemicals are in the system?

Pin holing due to faulty water can occur in a very short time!

Tony

 

[gas112]

ignore Agile it just a leaking rad

 

[bernardgreen]

Pin holing due to faulty water can occur in a very short time!

"faulty water" can accelerate the development on pin holes in faulty metal.

ignore Agile it just a leaking rad

Why ignore the explaination of the leak.

 

[gas112]

I would have to kill you if i told you . google it as you normally do

 

[bernardgreen]

I would have to kill you if i told you . google it as you normally do

Could I possibly rely on recall of information supplied by a friend who worked in Quality Assurance at Llanelli Radiators ( Morris Motors as was ) about the number of grots ( maybe the wrong word ) of impurity found in sheet metal. Bits of grit pressed into and sometimes all the way through the metal sheet as it was rolled. Water tight fit into the metal at first but after a few cycles of temperature changes it was no longer water tight and "pin hole" leaks develop.

Of course these were mostly car radiators so in no way can this be applicable to central heating radiators. so google it is.......

 

[Dan Robinson]

You crack on.

 

[PChris]

Thanks for all your replies - the radiator was replaced because it's part of the new kitchen we have had fitted and the old rad was 20 years old and we wanted something different. The water is all good in the system - I now think it must be a fault in the radiator itself -it's only been on a handful of times, not that cold this year!!

 

[Mikefromlondon]

Good job you turned it off, it would have flooded your house if it had burst. That would been total disaster!

 

[Agile]

The water is all good in the system

How do you know that?

Have you had it tested?

Or you just look at it and say "it looks like water and so must be good"?

 

[gas112]

Agile give up ,its a bad weld as many of us who actually have experience know , its not an unusual occurrence with this sort of rad. you can even see the bubble is forming right by the weld