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Harman P series heat shields. Info/Pics? Minimum clearances = yikes

Post in 'The Pellet Mill - Pellet and Multifuel Stoves' started by P38X2, Oct 14, 2012.

  1. P38X2

    P38X2 Minister of Fire

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    Hello everyone. Nice to see the forum is still going strong and no one's put an eye out.

    One of my stoves is corner installed using Harman's minimum clearances. I found my IR thermometer buried in the junk drawer and decided to play with it. After running the stove at around 3/4 output for about 15 minutes I took a reading of the painted drywall to the sides. 137F...after only 15 min:eek: The wall was disturbingly hot to the touch and the paint was getting gummy feeling. Now, I understand the latex paint flash point is higher than that and its a UL tested appliance, but there's NO WAY am I not addressing this issue. I knew it would get warm but not like that.

    My first thought was to put 1/4" cement board on the side walls and cover them with 12" granite tiles...which would match my hearth nicely. I'm sure that would work well but I'd rather not fart around with that project if there's an easier option. Which apparently there is.....

    I'm looking into the Harman heat shield kit. How/where does it attach to the stove? Anyone have pics they'd be willing to upload? I've found only one pic that 'gfreek' posted last year but it doesn't show the fastening points. IMO, it looks slick.....very "factory" looking.

    Thanks
    -Mike
    Luv2burnPellets likes this.

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  2. mepellet

    mepellet Minister of Fire

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    I worry about the high drywall temps also. I took some readings while running in stove temp. I am pretty sure that they were higher than 137. I could dig them up for you if you'd like.

    Id be curios to see what your drywall temp is after running in stove temp 3 after a couple hours so we can compare.
  3. P38X2

    P38X2 Minister of Fire

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    I'd check but its 59 here and already too hot in the house. Like I said, it was only after 15 min of approx 3/4 throttle. There's no doubt in my mind it gets/has gotten much hotter than that. Is the wall going to burst into flames?...doubt it but neither would a 5 gallon jug of gasoline and I'm not about to store that next to the stove. That much heat sinking into the wall, surge protector, etc...can't be good.

    Judging by gfreek's pic and looking at my stove, it looks like the installation may require drilling into the main body of the stove. If that's the case, so be it.
  4. mepellet

    mepellet Minister of Fire

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    I dug up my findings. I measured 149 drywall surface temp when in stove temp 3 and 180 drywall surface temp when in stove temp 5.
  5. TheMightyMoe

    TheMightyMoe Minister of Fire

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    p38x2,

    How cold is it out? Once you start getting some heat loss, it should cool the walls considerably. I literally have a thermostat above my stove on the wall, and it rarely gets to a 100*, but when it was warm out, and I was doing test runs, it was getting well over 100*.
  6. mepellet

    mepellet Minister of Fire

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    The wall I was taking temps from is an interior wall.
  7. SmokeyTheBear

    SmokeyTheBear Minister of Fire

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    The lowest flash point for drywall is the flash point for the paper that faces it.

    The bonding of the paper to the actual gypsum base actually increases the flash point. You might want to look at the flash point of the paint if you know what paint was used.

    A decent drywalling job includes a skim coat which should take the facing paper out of the equation as it would be sandwiched between two non combustibles.
  8. tsmith

    tsmith Minister of Fire

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    1/2" drywall is supposed to have a 1 hour fire resistance rating to open flame. But I also saw that regular sheetrock can only withstand temperatures to 125 degrees unless you have fire rated drywall. That said, both of my stoves are in corner installs with just drywall around them.
  9. P38X2

    P38X2 Minister of Fire

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    Yes, interior wall painted with latex paint, which I think has a 195F flash point....though that seems a bit low...I hope. The paint is most definitely the weak link here. Skim coat on the drywall?...yeah right! Lol, not in these parts... although the drywallers did an excellent job.

    180!? Sheesh. Again, prob "safe" but that gives me zero piece of mind which is priceless considering the consequences.

    Any info on the heat shield installation procedure?
  10. TheMightyMoe

    TheMightyMoe Minister of Fire

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    The reason I asked my earlier question is because I thought I would need heat shields with my P68. When I was testing my P68 maxxed out and it was 60* outside, my walls were reaching 150*. However...

    Once it got cold outside, and I ran on stove/room temp mode, the cold air from the home circulates around/through the stove, and your walls be much colder as well.

    Mine is a minimum install against a interior wall as well. Thermostat never read above 90* even when I was returning home from a set back (From 60* to 73* room temp)

    Attached Files:

  11. SmokeyTheBear

    SmokeyTheBear Minister of Fire

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  12. P38X2

    P38X2 Minister of Fire

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    TheMightyMoe, interesting yet hard to rationalize, though I'm not doubting you. NH gets cold but not AK cold so perhaps that's where the difference lies.

    Smokey, thanks for the info. I poked around the internet and found several sites that stated latex paint is nonflammable.... but I ain't buying that for a second.

    As safe as my setup may be, it's bugging me. I'm gonna be worried about it when I'm at work or wherever. I'm still wondering about the effectiveness of the shields. I believe Harman states that it reduces the minimum clearance from 16" to 10" so I assume they'll do the trick and sooth my paranoia.
  13. TheMightyMoe

    TheMightyMoe Minister of Fire

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    Yeah, everything is situational i suppose,I also forgot the 38 isn't as modular as other harman models, Wish mine always put out that much radiant heat, then there would be a non- aesthetic reason to make a hearth. Hope someone has the info your looking for. Also if you up distribution fan speed does it affect the radiant output?
  14. gfreek

    gfreek Minister of Fire

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    Hey P38X2, they attach to the rear of the stove's burn box. Between the hopper and the stove itself with one bolt. I had my dealer install them before delivery. Will post pic later if no one does sooner....
  15. SmokeyTheBear

    SmokeyTheBear Minister of Fire

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    It's ignition temperature puts it out of materials that are regulated as a flammable substance for the purposes of storage and transportation.
  16. P38X2

    P38X2 Minister of Fire

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    Haven't actually checked but I assume it does to a point. I'm tempted to go with granite on the walls to increase the radiant surface area but...too lazy these days.

    Did it require removing the hopper?
  17. P38X2

    P38X2 Minister of Fire

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    Gfreek, I just called my dealer and got my answer so posting a pic isn't necessary, but I appreciate the offer and help. I'm shutting down my stove to get these things on, then I'll post a pic. Supposed to be 70 today so my not so scientific results won't be posted til another day.
  18. P38X2

    P38X2 Minister of Fire

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    K, shields installed. Piece of cake. 1 bolt on each side between the firebox and the hopper holds each respective shield. The sheilds have a hole with a slot cut into them. Just needed to expose 1/4" or so of the threads of the bolt on the back of the firebox, pop the shield over the bolthead, slide the slot in the shield onto the threads of the bolt and tighten. It took no more than a minute per side.

    Top pic shows the bolt that holds the shield. It's the one in the upper flashlight spot. The next pic is the finished product.
    IMG_2012101514341.jpg IMG_2012101532401.jpg
  19. mepellet

    mepellet Minister of Fire

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    Nice! Mind sharing what they cost you?
  20. P38X2

    P38X2 Minister of Fire

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    Thanks : ) $77
  21. gfreek

    gfreek Minister of Fire

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    You got it....
  22. mepellet

    mepellet Minister of Fire

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    P38X2-
    Have you noticed a hugger difference in drywall temperatures?
  23. P38X2

    P38X2 Minister of Fire

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    Yep. Huge difference. Can't really take a "scientific" comparative reading right now. It's considerably colder outside than that day and the stove is currently on low. Very happy with the purchase.

    Are you considering them?
  24. mepellet

    mepellet Minister of Fire

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    Yes I am. I just hooked up a programmable thermostat and worry about the drive cranking on high when I want the room to warm up several degrees. I assume the shields for the p61 are more than the p38. I will call sometime.
  25. P38X2

    P38X2 Minister of Fire

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    Not sure what you mean. Are you saying your thermostat is in close proximity to the stove and you're worried about radiant heat throwing off the readings?

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