Fire alarm

[Southspark85]

hi all any help would be appreciated. Been asked to sort out a smoke alarm which is linked to the kitchen door but not to the fire alarm.

I have attached attached a photo of the plan he gave me which states linked to door not fire alarm circuit. He has a 24v over door magnetic holdback which he wants to use again. Anyone done this before and what's the best way to do it?

 

[Strima]

Why would you link a smoke alarm to a door? And why not a heat in the kitchen?

 

[Southspark85]

I'm not sure it has a heat alarm but asked for a smoke which is not linked to fire alarm. I'm guessing that means a mains power aico smoke to release the door if it sound rather than setting the fire alarm off with false alarms. Not sure if that is correct if anyone has any ideas would be appreciated

 

[telectrix]

sounds like that's what he wants. normally this idea is used with fire alarm control panels so when the alarm activates, a 24V relay de=energises the door magnet. can't see how it can work with domestic smokes such as aico.

 

[Southspark85]

sounds like that's what he wants. normally this idea is used with fire alarm control panels so when the alarm activates, a 24V relay de=energises the door magnet. can't see how it can work with domestic smokes such as aico.

Only thing I thought was to use a aico relay base so if smoke goes off will release the door magnet. Only thing I'm not sure on is shouldn't all the fire doors close off the fire alarm circuit and doing this wouldn't release the kitchen door with the rest of the doors on the fire alarm. Also the overdoor is 24v so guessing a separate psu just for the one door is required. Seems a lot of messing about for one door and one smoke alarm

 

[Rocboni]

Aico relay base, with magnetic door holdback wired through the NC contact via a 24v psu?

Ei128R Hard Wired Relay Module - Aico - https://www.aico.co.uk/product/ei128r-hard-wired-relay-module/

Not sure why you would though?

 

[Octopus]

Why would you have a smoke alarm in a kitchen, when there is a heat alarm in the same room?

Maybe ask the person who did the design?

 

[Southspark85]

Aico relay base, with magnetic door holdback wired through the NC contact via a 24v psu?

Ei128R Hard Wired Relay Module - Aico - https://www.aico.co.uk/product/ei128r-hard-wired-relay-module

I was thinking the same as you but seems a lot of work for the one smoke and door.
Apparently that's what a architec has told him is required.

 

[Southspark85]

Why would you have a smoke alarm in a kitchen, when there is a heat alarm in the same room?

Maybe ask the person who did the design?

He says in another care home he's got they put a smoke in the same as his plans shown. The only way I can see doing it would be via a separate psu and aico relay base.

 

[Rocboni]

All that's going to happen is the door is going to close all the time from false activation, that's why heat detectors are fitted in the first place.

 

[Southspark85]

All that's going to happen is the door is going to close all the time from false activation, that's why heat detectors are fitted in the first place.

I'm only guessing it's to prevent evacuating residents is the toast is burnt etc

 

[westward10]

I suspect the entrance hall is a protected route and the door release and smoke detector are in place to prevent smoke on this route. It is possible the kitchen door which would form protection to a compartment opening could be left wedged open which would allow spread of smoke to the hall if a fire went unnoticed and the heat detector failed to activate the system so the best option is to fit a door mag with smoke detector.

 

[Southspark85]

I suspect the entrance hall is a protected route and the door release and smoke detector are in place to prevent smoke on this route. It is possible the kitchen door which would form protection to a compartment opening could be left wedged open which would allow spread of smoke to the hall if a fire went unnoticed and the heat detector failed to activate the system so the best option is to fit a door mag with smoke detector.

So would you say using the aico with relay base then a separate psu for the kitchen door only is the best way to do it?

 

[westward10]

So would you say using the aico with relay base then a separate psu for the kitchen door only is the best way to do it?

Never done this for a Part 6 system why don't you contact Aico.

 

[Southspark85]

Never done this for a Part 6 system why don't you contact Aico.

Aico said they don't do psu but the relay base can be feed from a 24v supply which would then allow the magnetic door holders to work of the base. This is the only way I can see how it can work from the details he's given me

 

[westward10]

Sounds like the best option. You should also identify the smoke detector as being standalone and not connected to the main system.

 

[Southspark85]

Sounds like the best option. You should also identify the smoke detector as being standalone and not connected to the main system.

Will do thanks for your thoughts

 

[telectrix]

and when the door is propped open with the kitchen fire extinguisher?

 

[freddo]

and when the door is propped open with the kitchen fire extinguisher?

Chain the extinguisher to the wall, chain long enough to spray the kitchen fire, but not long enough to prop the door open.

 

[Devonchris]

If its just a stand alone arrangement and not subject to fire safety approval then something like this may work with a stand alone detector? You would need to ensure that it would fail safe and not compromise the existing alarm/ fire door set up.

Black Dorgard Fire Door Retainer - https://www.safelincs.co.uk/black-dorgard-fire-door-holder/?fGB=true&gclid=Cj0KCQjw4eXPBRCtARIsADvOjY2y8d2q63sHeBeLRy-MUln_zIq7T-6LL8CtE22SCfx9ICdtk_E-xUcaAnsGEALw_wcB

 

[Devonchris]

You need to ensure that the door closes when either the stand alone or main alarm goes off. The acoustic option may be easier than two trigger feeds for the contactor. I suppose it will depend on the sensitivity and volume of the main alarm.