High-ambient-temp smoke sensor recommendation

[Behemot]

Not sure if this is the best section, so feel free to move it. I'm tasked to get some "safety device" in case something goes wrong to insure a dry sauna does not burn again. This time the wall with stove on it has been covered with mineral insulation material as well as linings. (Harvia states their stove can be mounted directly on wooden walls! get that! ).

Idiots wired extra (UTP, get that second time ) cable to the sauna ceiling. Is there ANY smoke detector which could survive on the ceiling with up to 100 (120?) °C there, or just all those house toys good for up to about 70 °C?

I don't want no stupid HEAT detector as there is obviously heat in the room, besides, that could only do something only if there is EXCESSIVE heat like that from an open fire Quite useless. Smoke sensor/detector at least has an actual chance to shut the system down when it is only smoking, not yet openly burning, maybe even preventing from something catching real fire.

[KYBOSH]

Re: High-ambient-temp smoke sensor recommendation

How about something like this?

[Behemot]

Re: High-ambient-temp smoke sensor recommendation

that is one of the solutions - when somebody uses their brains and prepares the installation BEFORE everything is finished the sauna is pretty much done, there's one spare cable in position (though wrong, PVC on sauna ceiling, where there is as much as 110 °C while in operation?!)

we'll most likely install second original HEAT sensor (not that it's much of use IMO) and possibly put ordinary smoke detecter from outside, over the door

I've searched instensively, found pretty much nothing over 70 °C, all that is usually heat sensors

[KYBOSH]

Re: High-ambient-temp smoke sensor recommendation

I dont know the layout of the sauna in question but I cant imagine a situation where something like the duct smoke detector or something similar (with some sort of ionization detection probe) cant be installed retroactively. I am no expert tho.

[Behemot]

Re: High-ambient-temp smoke sensor recommendation

problem is, where to put the cabling so it is not visible

[stj]

Re: High-ambient-temp smoke sensor recommendation

build an old school smoke detector.
a chamber with a divider down the center
one side open the other side sealed.
a light souce in the center and a sensor at the end of each side of the chamber
if smoke passes through the open side the sensors with give different outputs
you can feed the sensors into a comparator chip like an LM311

by using 2 identical sensors and a single light source your not effected by variation in the light source or sensors due to temperature or age.
the only difference is one can be obstructed by smoke and the other cant because it's sealed.

the other option is to use a heat alarm instead of a smoke alarm - these are often used in kitchens

[KYBOSH]

Re: High-ambient-temp smoke sensor recommendation

build an old school smoke detector.
a chamber with a divider down the center
one side open the other side sealed.
a light souce in the center and a sensor at the end of each side of the chamber
if smoke passes through the open side the sensors with give different outputs
you can feed the sensors into a comparator chip like an LM311

by using 2 identical sensors and a single light source your not effected by variation in the light source or sensors due to temperature or age.
the only difference is one can be obstructed by smoke and the other cant because it's sealed.

the other option is to use a heat alarm instead of a smoke alarm - these are often used in kitchens

Would this be able to differentiate between smoke and steam?

[stj]

Re: High-ambient-temp smoke sensor recommendation

interesting question

[KYBOSH]

Re: High-ambient-temp smoke sensor recommendation

interesting question

It would seem like we'd have to go with an ionization smoke detector as opposed to a photoelectric smoke detector for this application as ionization alarms are not affected by normal levels of cooking fumes or shower steam.

[Behemot]

Re: High-ambient-temp smoke sensor recommendation

cant make no kludge on my knee, if something happens, I'd be facing courts, thanks but no thanks! only buying factory stuff with all the paperwork already done

[KYBOSH]

Re: High-ambient-temp smoke sensor recommendation

Without a picture or make/model to reference its hard to fully appreciate or help with this issue. Sounds like the major issue is the heat source. Either its not rated for the task or its not being properly maintained. Perhaps it can be upgraded to something safer or with a higher rating?