Each coil draws .015A at 24VDC. Putting them in series would not be practical especially in a large building. There are systems that use 120VAC coils but the circuits have to have the correct cable, (Romex) pre wired for them.. Most buildings are wired using 18 or 16 AWG. FPLR low voltage cable for initiation and indicating circuits. You would not want to run 120V through these. Further, most fire alarm guys are certified in low voltage and although I wired my own house and I could certainly wire a 120V circuit, we are not electricians. For this reason all the door holders I've run into are the 24VDC variety.

I do like Michael's idea of video taping the failure and sending it to the manufacturer. Perhaps that will get them off their asses to come up with a solution. Lenny