director: Carl T. Montgomery
year: 1928
country: USA
history notes: Unidentified Film No. 210
alternative titles: Drei Helden von der Spritze

This film has been identified thanks to contributions from members of the Lost FIlms community.

American slapstick comedy about three large firemen, which here survives in the German distribution version from 1928 [frame scan 1]. The morning routine meets with all kinds of adversities [frame scans 2-5]. The chief and his daughter call a drill [frame scan 6]. However, the three heroes are not yet fit for service [frame scans 7 & 8]. After the drill comes an emergency call: fire! The mission does not proceed free from absurd incidents, however...

Cast: Hiliard 'Fat' Karr, Frank 'Fatty' Alexander, Kewpie Ross
Production Company: Larry Darmour Productions
Distributor: Deutsch-Russische Film-Allianz A.G. (Germany)
Length: 327m
Format: 35mm, 1.33:1
Picture/Sound: b/w, silent
Notes: 'Zeiss Ikon' edgecode; German version

Source notes
Deutsche Kinemathek - Museum für Film und Fernsehen

The given cast information came from the surviving German censorship card. So, that's very interesting what Steve says about the man standing in for "Kewpie" Ross, although Ross's name was the one mentioned on the card.

I've uploaded a still from my collection which identifies this as THE HAPPY TRIO (1928).

With relation to Steve Massa's comments, it's perhaps interesting to note that newspaper ads for THE HAPPY TRIO identify the cast either as "Three Fat Men" or "The Fat Men", rather than specifically naming them as Alexander, Karr, and Ross, as had previously been the case in ads for other shorts in the series.

German censorship info: 2 Acts, 435m, silent, 'G'-rated, Permit No. 20944, 26.11.1928. We are after the original title and year of production.

The release date for THE HAPPY TRIO is 3/12/1928.

This is one of the "Ton of Fun" series started by producer Joe Rock for Standard Comedies in 1925. The series lasted until 1928 and Larry Darmour took over the producing chores for the latter ones, which were mostly directed by silent comedy veteran Earl T. Montgomery, who had been part of the team of Montgomery and Rock, with Joe Rock, at Vitagraph in the late 'teens.

This looks like it's one of the last of the series with Frank Alexander and Hilliard Karr still in place, but the third fat guy (iseen in the frame scan with the hatchet near his head) is not William "Kewpie" Ross, but another large guy who seems to be filling in.

I'll look for a review that identifies them as firemen, but the series was more frequently reviewed in its early days.