piano distuning

[alex_of_sc]

Hello, my real name is Alexandre, I play piano since 10 year.
My piano is a Kaluga.
I tuned my piano since 10 month. After i tuned, I greased my forte pedal because it grated.
After this, my piano was distuning on some strings. Those string are on the zone I greased.
But, i have a doubt about it, beacause my piano was near the chimney of the house, i know
this is very harmful for an music instrument.
I don't know why my piano distuned, the strings are old.