heater switch

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hoggie
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Thu Sep 27, 2012 10:12 pm

Hi
When I turn on the heater nothing happens until I get to the 4th setting and it works at full tilt as normal but nothing on the first 3 settings.Is the switch causing it?
thanks
sweep
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Location: spares & repairs in sheffield

Thu Sep 27, 2012 10:21 pm

its the resistor by the sounds of it
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Brianmoooore
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Thu Sep 27, 2012 11:22 pm

sweep wrote:its the resistor by the sounds of it
And the usual cause of that failing is a fan motor whose bearings are beginning to seize through lack of lubrication.
Grrrmachine
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Fri Sep 28, 2012 6:23 am

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hoggie
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Sat Sep 29, 2012 8:35 am

Can i check the resistance with a meter is there a value the resistance should be
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Brianmoooore
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Sat Sep 29, 2012 10:15 am

The resistances are very low - 0.8, 1.0 and 1.6 ohms, and there's also a thermal cut out on the pack that should have zero ohms between its contacts. The cut out is the usual part that fails (on the small brown version at least), and as I've said further up, this is usually caused by a partially seized fan motor stressing the cut out.
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