Other mistake: After Early carries Martha into treatment 3, and he and Brackett begin examining her, there's a nice exterior shot of what is supposed to be Rampart, only it's not actually Rampart, and we know this since throughout the show's run there are numerous exterior shots of Rampart from every angle.
Other mistake: At 6:50 AM, just before the dispatcher transmits the testing tones to Station 51 which wakes everyone up, we're shown the exterior shot of the station and the two flags are already flying. Guys of C shift (as Chet states) haven't arrived yet that morning, so they didn't raise the flags, and we know it's Mike who always raises the flags on A shift, but he only just woke up when the dispatcher sent the tones.
Other mistake: When Station 51 is dispatched to the structure fire, the address is given as 1127 West Winston, but when they're on the scene, the fire flashes through the front door causing Marco and Chet to fall back, and the house number on the stairs is 1026.
Answer: I believe you are speaking of the old man, Mr. Wilson. He's played by J. Pat O'Malley.
Bishop73
Correct, it was J. Pat O'Malley...he also played the grandfather with his grandson when their rocket exploded, and also played "Old Bill" in the episode with Ann Prentiss, where Gage saves the little girl from the burning tree house, and her mother falls in love with him.