Can you buy core plugs seperately for…

[kroc_kroc]

so it sounds like the heat exchanger needs to be replaced again. Apparently those items on the side (whatever they're called) were factory fitted and come with the exchanger.

Would I be better off buying a new boiler? because as far as I can see this is just going to keep happening. If I do replace the boiler or heat exchanger I will get the system flushed but I'd rather spend a bit more money in the short term to have longg term peace.

Are Potterton boliers any good or should I go for a different make?

Any recommendations?

 

[TicklyT]

Same Q as Doitall, what are you calling core plugs?
Do you mean on the left and right ends of the casting?
These look like simple flat U shaped steel, bashed into place whereupon they go "over centre" and spring out to grip. They corrode like fury in cast iron - like they did in Leyland cars, given a chance. They are relatively easy to remove and come in lots of sizes off the shelf.
If you pop-rivet into the centre and pull, the plug comes back from over-centre with a pop and then comes out easily - ish.

IIRC 'core plugs' are pan shaped plugs that are pressed into parallel bored holes in castings. Welch plugs are slightly dished discs that are pressed into stepped holes in castings, then flattened to expand the edges and grip the bore.

Both Welch plugs and core plugs are available in a multitude of sizes, often from motor factors, as they are commonly used in car engines.