Question about leaking GB142

invermont

I’m already looking to replace this system just trying to figure a few things out. I have a leak outside the casing. Only drips when the boiler stops running.. It is dripping down the outside of the back of the boiler. Am I right in thinking it’s not the hx? Wouldn’t I lose system pressure? Everything seems normal. Just started with this extreme cold.

I was thinking that maybe the condensation is freezing then melting back into the flue and escaping somewhere. Condensate tee may be clogged and not letting water flow back? When I take the bottom off I don’t see any water in the flue exit.

I would figure if the hx was leaking it would be inside the case.