A question about Simplex 4051s

I just got back from a road trip. In the hotel I stayed at one night, there were Simplex 4251-20 pulls, TrueAlarm Smokes, Simplex ‘Bell-Shaped’ heats, and 4051s for the notification appliances. There were Faraday strobes scattered around as well. My question is, are 4051s codeable to do march time, code-3, etc…? Also, if they renovate the building and get a new panel, will the 4051s still be compatible, and, will the 4051s need to be replaced?

The 4051 is a simple 24 volt DC appliance. Connect 24 VDC to it and it makes noise. Yes it can be coded by the fire alarm control panel turning the circuit on and off at the desired rate. They have no internal coding ability.

If the panel was replaced the 4051s most likely are compatible. That probably would be done as a panel replacement for service reasons. Like if the old panel is failing and repair parts are no longer available. Most AHJs have a policy of allowing the panel only to be replaced without bringing a system up to current code. In this case the company doing the work would survey the existing field devices and choose a panel that is compatible with them.

If the building goes through a complete top to bottom remodel the 4051s probably would be replaced. The AHJ usually requires the system to be brought up to their current code requirements in a complete remodel. The current code probably would require additional notification appliances. An extensive remodel many times involves the services of an architect and several engineers. Architects and engineers like uniformity in a building they design whether new or a complete remodel. The other item they like is to supply the building owner a full 1 year warranty on all systems that were upgraded. Leaving old fire alarm devices could end up in a “this new device is under warranty but these old ones are not” finger pointing situation.