I got a kerosene heater a week or so ago, burned it in (according to milesstair.com's instructions) in the garage for about an hour or two and i've followed all the instructions in the manual.  Additionally, i've read a number of the threads here on kerosene heaters.  For some reason i just can't figure this damn thing out - it's been probably 2 decades since i've used one of these and i figured i'd not have any issues after cranking it up a couple times.

I bought this house about a year ago and it has combination smoke detectors/ CO alarms.  Two of them in the living area - one is on the ceiling about 18' off the ground and about 40 feet away from where i've placed the heater.  The other is in a hallway about 30 feet away and 10' off the floor.  The alarm in the highest area keeps friggin' going off after 15 minutes or so in the house and i swear i have the flame adjusted right. (Pics of the flame height from the last episode to follow).  The detector in the hallway hasn't gone off once - the other one has gone off 3 times now. The back part of the burner doesn't have a nice flame like the rest of the burner.  

Heater:
hMHC-2230 HeatMate (Sengoku)
K1 Kerosene i use in my lamps

What i'm doing:

starting heater outside and letting it warm up for 5-10 minutes before bringing it inside
place heater in the middle of the room (about halfway between the two detectors)
monitoring and adjusting flame height as needed once inside





So the back part of the burner looks low - the rest looks fine.  Or is all of the flame too low?

I don't have an idea why the CO / smoke detector is going off... does it indicate CO or smoke ?... or just an alarm ?

I have a similar heater ( Dynaglo )... the flame height looks about right.... if anything a " shade " high.
The flame on mine is not perfectly uniform either.... Personally, I adjust mine when the light goes from a yellow to white... then look inside to make sure it's correct.

EDIT: CO is heavier than air  see below...  ... I'm thinking a battery powered detector about 3 feet off the floor would be best.


Good luck & stay safe.

Flame looks fine to me.  I actually run two in my house in the evening––one downstairs and one up.  CO2 detector is upstairs only a few feet from the heater, and it's never made a peep.  Smoke detectors all over the house.  They'll go off if we burn microwave popcorn, but the Kero heaters have never set them off.

I wonder if your detectors have some kind of heat sensor/detector in them that goes off with the (relatively) rapid change in temp from running the heaters?  Remember––the heat from these things rise and collect quickly in the upper parts of the rooms.

That flame looks perfect. Do you have a way to tell if its CO or smoke?


I am guessing that its smoke that its detecting, but no promises.

I read that CO is the same density as air, another guy told me that it is lighter, and now someone is saying its lower density. I sure wish someone would clear that up for everyone.

I just checked wiki... it's SLIGHTLY LIGHTER than air... http://en.wikipedia.org/wiki/Carbon_monoxide

" Molecular properties

Carbon monoxide has a molar mass of 28.0, which makes it slightly lighter than air, whose average molar mass is 28.8. According to the ideal gas law, CO is therefore less dense than air. Neither gas is "ideal", however, so the exact densities and other comparative values depend upon temperature and pressure. "

every 15min sounds like the batteries in the CO detector are getting weak. change them and see if its still going off.

Detector doesn't go off every 15 minutes -  it only takes 15 minutes of the heater being on before it goes off.  No heater = no alarm.  heater in house = ~15 mins before detector goes off and a couple mins after the heater is removed from the the house, it shuts up.

flame looks fine. these things dont give off that much C02, like 2% or less. mine is cranking out crazy BTU's, im ok. crack a window, and dont letit burn too hot. may have a fuel issue.

my c02 detector has not made a peep.

keep at it, youre on the rite track.

This

switch the 2 detectors and see if it still goes off. could be an issue with that detector.

most CO detectors dont usually have heat detectors built in. some smoke detectors do though.

Ok, so i was incorrect here.  I grabbed a ladder and took the detector off the ceiling.  It's a Firex 120-1072B model smoke detector, not a CO/ smoke combined.  That's all it says about it.  It's hardwired into 120V house power.  I can't find a manual for it anywhere, however I did find the replacement is a Kidde i4618 smoke detector that includes "ionization sensing technology".  After researching this, the problem wih the alarm going off is easily understood.  

Excerpt from the EPA website:


So basically, the air at ceiling level is getting too hot too fast and tripping the alarm.  Now this is a royal pain in the ass since I don't want to keep this disconnected and you cna't really control the amount of heat coming from the heater.  I'm going to try and locate the heater in an area farther from the detector and hope the ambient air will take more time heating up and allow the detector to maintain it's quiet mode.  If that doesn't work, I really have no idea how to solve the situation..  I don't want to disconnect the detectors, if i moved them to another location i'd have to terminate wiring and patch up a hole, which i really don't wanna do ither. Any ideas?

do you have a ceiling fan to run so it will push the heat down? Mixing up the air should help some.