that is sad news considering you have been waiting for over a year :'(
I applied under NOC 2242 and I can remember my reference letter from my employer itemizing my duties which included installation, servicing, and repair of alarm, fire, cctv, and access control systems...
Apart from fire systems what else did your letter speak of? were you formally trained on fire systems and other aspects of electronic systems?
I'm not 100% sure of the criteria for working in this field of work but I had to present all my certificates as proof of knowledge, I know of at least 3 associates who tried to obtain W/P under 2242 and were denied based on their inability to demonstrate knowledge in this field.
If you wish i can PM you my actual reference letter so you can see how it was structured (it will take me a few days since i'M away for the Easter.
good Luck!