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FIRE SERVICE AND GENERAL FIRE SAFETY TOPICS => Technical Advice => Topic started by: Big_Fella on January 29, 2009, 11:15:28 AM

Title: Detectors in Chimneys
Post by: Big_Fella on January 29, 2009, 11:15:28 AM

I've just been asked a question I don't have the answer to, and wondered if anyone has a solution...

A detector for use within a chimney.

Any ideas, types of detector recommended etc?

Thanks in advance

Title: Re: Detectors in Chimneys
Post by: nearlythere on January 29, 2009, 11:16:53 AM

Quote from: Big_Fella on January 29, 2009, 11:15:28 AM

I've just been asked a question I don't have the answer to, and wondered if anyone has a solution...

A detector for use within a chimney.

Any ideas, types of detector recommended etc?

Thanks in advance

For what reason?

Title: Re: Detectors in Chimneys
Post by: Big_Fella on January 29, 2009, 11:28:09 AM

The site is a fairly old manor house, and they are worried 'something' might catch alight above the fire place in the stack, and they are after an early warning of such an instance.  Obviously the stacks should be regularly cleaned to prevent such instances but this is their request.

Title: Re: Detectors in Chimneys
Post by: Allen Higginson on January 29, 2009, 12:17:58 PM

I suppose if you knew what the maximum heat was within the stack from a specific distance you could install heat detection to activate above this (set at a percentage above the ambient) but,that aside,can't think of anything alse.

Title: Re: Detectors in Chimneys
Post by: Graeme on January 29, 2009, 01:04:02 PM

probe heat detector or linear?

This is the first time i have heard of this being asked.

i would however avoid a smoke detector ;D

Title: Re: Detectors in Chimneys
Post by: GregC on January 29, 2009, 01:20:53 PM

Would the budget allow for a flame detector ?

Title: Re: Detectors in Chimneys
Post by: Mr. P on January 29, 2009, 02:57:04 PM

May be cheaper to line the chimney...

Title: Re: Detectors in Chimneys
Post by: Morri on January 29, 2009, 03:02:40 PM

Agree with Mr P, remove the hazard if it is a genuine concern

Title: Re: Detectors in Chimneys
Post by: Allen Higginson on January 29, 2009, 05:48:55 PM

Quote from: GregC on January 29, 2009, 01:20:53 PM

Would the budget allow for a flame detector ?

Dirty enviroment and,depending where they want protection to be located,false alarms liable.

Title: Re: Detectors in Chimneys
Post by: John Webb on January 29, 2009, 08:57:02 PM

I think the best solution would be industrial standard sheathed thermocouples. These can be easily monitored and with an Iconal or stainless steel sheath will resist soot, heat and other corrosive gases. We used them regularly in large fire tests to measure gas and flame temperatures and they rarely needed replacement. Not quite to BS5836 but as that doesn't quite cover this particular area anyway...