Repair frost-damaged outdoor fireplace

[ByggHenkebus]

Hello
Had a mason here last year to put a new bottom in our outdoor fireplace. Firebricks and fireproof mortar. He also smeared some white mortar to fix smaller cracks.
It lasted for almost 60 years, so imagine my surprise when the frost damage came...

The yellow color is silicate paint that the whole house was painted with about 30 years ago.

How should I plaster/repair and how should I paint?
Thankful!

 

[Hybro]

The foundation seems good, not a crack as far as I can see in connection to the house's wall. Well worth renovating.

You should try to find the manufacturer of that phenomenally good paint, which has lasted so long.

A tip is to stash away the garden hose, already in the autumn.
So there won't be any idle watering during the cold season.