My fire alarm won't stop beeping! Help!

[Ridiculousradish]

Fire alarm started chirping at 4:30am. Have removed the battery and replaced with a new one. It's hard wired to the electrics, and was still beeping when the electricity had been turned off. What is this madness?

Property is rented, but landlord is useless at sending people round. Am hoping I can sort this myself.
Thank you!

Carbon monoxide and fire alarm to separate things in all the properties we've been in. And we had this in last house had to hold in button and count to 20 then it reset

Mine did this and it was the smoke alarm that was dead and it kept randomly going off too then beeping constantly
Disconnect it from the wiring and take it down
I just replaced mine with a new one

@LauderSyme I like your style!

@Sageyboots that's interesting. I'll do some Googling. Thanks

Landlord has replied! Just suggested I press the reset button. Told me he can look at it tomorrow morn, but I'm at work. Just going to see if I can sort it myself.

Our carbon monoxide one went before it's 'sell by' so they don't always last

When the smoke alarm gave up the ghost we just had to take it out, disconnect the hard wired bit (should be easy as it's a push pull fitting) until we could get a new one

Luckily we had another upstairs so wasn't without one