Another Space Heater question

Discussion in 'General Electronics Chat' started by Gdrumm, Jan 5, 2015.

  1. Gdrumm

    Thread Starter Distinguished Member

    Aug 29, 2008
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    Someone threw away a Space Heater, and I snagged it.

    Initially, the fan blade wouldn't turn.

    I cleaned up the fan shaft, and used some WD 40, and it started working.

    The problem now is that it heats good for a few minutes, then shuts off, even though the room is not warm yet. It does have a thermostat.

    I have since cleaned the contactors on both the small thermal breaker (below the thermal fuse in the photo), and I cleaned between the contacts on the Tip Over / Temperature Adjuster.

    Does anyone have any insights on what might cause it to shut off, beyond the items I've mentioned.

    Everything inside looks fairly new, heater springs, etc.

    Thanks,
    Gary
     
  2. MrChips

    Moderator

    Oct 2, 2009
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    This is a thermal cut out switch:

    [​IMG]

    Run the heater until it cuts out. Then temporarily jumper across this device and see if the heater comes on.

    If that is the problem, replace this device, the thermal switch, with the correct temperature trip point.
     
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  3. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Should be easy to trace with a meter?
    Max.
     
  4. KMoffett

    AAC Fanatic!

    Dec 19, 2007
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    WD40 (Water Displacement formula#4o) is not a lubricant. It gets gummy over time.

    Ken
     
  5. KJ6EAD

    Senior Member

    Apr 30, 2011
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    The seized motor that you freed up enough to run may still be running slow enough to trip the thermal fuse. This type of heater should have enough air flow to prevent the coils from glowing orange.
     
  6. Gdrumm

    Thread Starter Distinguished Member

    Aug 29, 2008
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    What type of lube would you recommend?
    Thanks,
    Gary

    Will try the jumper technique.
    I did run a small file over the contacts on the tilt off / thermoswitch, (the whatchamacallit in photo 0002) but that didn't help.
    After a few minutes, it shuts off, then surges on-off, on-off, on-off, but never fully on.

    Hope that makes sense.
     
  7. #12

    Expert

    Nov 30, 2010
    16,246
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    That is a meltable link. It will not reset.
     
  8. wayneh

    Expert

    Sep 9, 2010
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    My thinking exactly. Just because it is turning does not mean it is running at design airflow.
     
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  9. Gdrumm

    Thread Starter Distinguished Member

    Aug 29, 2008
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    When I run it in Fan mode only, it seems to run fine.
    Only when heat is on (low or high) does it cut off.

    After it sets for a minute or two, I can turn it back on and it will run for a few minutes more.
    I tried prying open the fins wider, fore and aft, and drilled a couple of Quarter sized holes Port and Starboard, and that didn't help.

    I'll try the jumper technique tomorrow, and watch it closely.

    I'm pretty sure it's the "whatchamacallit thingamajig" that shuts the thing down if tilted, and adjusts for higher lower temp.

    Does anyone know the real name for photo 0002?

    I call it a thermoswitch / killswitch.

    But I might want to buy a couple for my parts stash.

    Thanks again
     
  10. wayneh

    Expert

    Sep 9, 2010
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    But that's my point. You can't judge the rpm very well. Does it feel very loose by hand turning? You should feel little to no resistance.
     
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  11. tcmtech

    Well-Known Member

    Nov 4, 2013
    2,028
    1,614
    I would start by giving the connectors in the thrmostat a good cleaning followed by soldering them solid.
    On those types of heaters the spade connectors tend to get corroded and weak causing them to heat up when the higher current load from the heating elements is on.

    Oil wise a drop or two of most any transmission fluid does wonders for those small motors.
     
  12. Gdrumm

    Thread Starter Distinguished Member

    Aug 29, 2008
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    The fan is very easy to turn now, no resitance at all

    Would soldering the contacts create any safety concerns, would the safety tilt shut off still work?
    I don't really need variable heat, just full on will do.
    It's located in an open space in my classroom, so no curtains or carpet to worry about.

    Great tip, Thanks,

    Thanks for the Tranmission Fluid tip as well.
    I don't know how many motor shafts and bearings I've sprayed WD40 on over the years.
    Then, in a month or so I had to do it again.
     
  13. KMoffett

    AAC Fanatic!

    Dec 19, 2007
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    It utterly amazes me how WD-40 is "miss-used".
    http://wd40.com/cool-stuff/history
    No where do they say anything about it being anything but a short term water displacer. They only talk about how their sales have increased. I have a gallon(!) of it in a machine shop where I work. I don't know why the previous manager bought it. According urban myths it must be the miracle liquid, second only to water. I guess a lot of people think "I need a fluid...WD-40 is a fluid...that'll work!". There are other fluids specifically optimized for every off-label use of WD-40.

    Rant over!

    Ken
     
  14. ian field

    Distinguished Member

    Oct 27, 2012
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    For most jobs I find the PTFE enhanced lubricants well worth the extra money.

    Instead of WD40 I use GT85 - but as others have pointed out, that's not a long service lubricant.

    I frequently use Slick 50 PTFE engine oil additive as a lubricant, and it does an excellent job.

    The PTFE grease I use is Finish-line PTFE fortified, from most bicycle shops.

    On any steel to steel moving parts, there's some advantage in treating with molybdenum lubricants a few times before continuing with PTFE.

    A good trick to prevent seizing of large threads, is a wrap around the thread of plumber's PTFE tape.
     
  15. MaxHeadRoom

    Expert

    Jul 18, 2013
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    I know it is a slightly better coolant for machining aluminum.! ;)
    Max.
     
  16. KMoffett

    AAC Fanatic!

    Dec 19, 2007
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    Coolant or lubricant? Slightly better than...dry?

    Ken
     
  17. MaxHeadRoom

    Expert

    Jul 18, 2013
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    Both? I know there is optimum for machining aluminum, but you have to be spot on to prevent melting and welding of the chips, but often the exact grade/conditions of the material are not known, (I am not a machinist!).
    In a pinch Kerosene is almost as good.
    Max.
     
  18. Dr.killjoy

    Well-Known Member

    Apr 28, 2013
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    The good machining lubes and coolants cost alot of money and pretty fly everywhere to only get wasted ... So alot of machinists use what is cheap and works for what they are working on and in long run saving them money ...
     
  19. Lundwall_Paul

    Member

    Oct 18, 2011
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    It should rotate freely by hand sudden stops in the blade movement would indicate that it needs another cleaning preferably taken apart, flushed out and lubricated. 3 in 1 makes a light oil specifically for motors.
     
  20. Gdrumm

    Thread Starter Distinguished Member

    Aug 29, 2008
    684
    36
    I decided not to solder the contacts shut.

    I prefer to keep the tilt / kill switch functional.

    Which means, I'll have to replace it, because that's what is causing the problem.

    Thanks again for everyone's input.
     
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