This is the flow and return pipework and is connected into what would otherwise be a blanking cap or immersion element.
There’s a few possibilities of course but I’m wondering if it’s just two pipes of different lengths, flow at the bottom, return at the top of a direct cylinder and plumbed into a y plan.
The cylinder circulation is pretty much non existent but central heating is fine. I’ve tried googling all sorts but I’m getting nowhere finding a replacement.
Thanks.