QVI30, Quadra Fire gas insert beeping

[standby]

QuadraFire QVI30 gas insert (probly 20 years old): starts up and runs fine with remote,
fan comes on with snap switch, all good. After about 20-30 minutes begins to beep.
Sometimes we can hit remote on/off momentarily and it will stop. Normally we have to turn off stove.
Fan keeps running until cool, all good.
Randomly, every few days or so, it will beep without being on, middle of night.
We stop that by pushing remote on/off without turning on stove.
Ideas on the beeping?

 

[standby]

turns out it was some kinda safety thing
fire extinguisher in kitchen handy enough to get it all out
lucky we were home, i suppose
oh well

 

[Burnin Since 1989]

turns out it was some kinda safety thing
fire extinguisher in kitchen handy enough to get it all out
lucky we were home, i suppose
oh well

What was the beeping warning you about? Was there some sort of fire? I keep a fire extinguisher nearby, just in case.