Can I replace a two wire Honeywell thermostat with a multi wire one?

I have a old two wire furnace system with a Honeywell T87F1818 3. Can I replace it with a Honeywell T87F1800 3. And just keep to unit set to heat and not cool and the fan set to auto?
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If you put a three wire stat on a two wire system, what makes you think "fan set to auto" will do any good?
Christopher A. Young Learn more about Jesus www.lds.org .
I have a old two wire furnace system with a Honeywell T87F1818 3. Can I replace it with a Honeywell T87F1800 3. And just keep to unit set to heat and not cool and the fan set to auto?
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at all, dumbass?
Christopher A. Young Learn more about Jesus www.lds.org .
Where else would you set it to on a heat only furnace. Dumb ass.
The King is dead but not forgotten.
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On Thu, 24 Jan 2013 15:16:47 -0800 (PST), snipped-for-privacy@hotmail.com wrote:

it with a Honeywell T87F1800 3. And just keep to unit set to heat and not cool and the fan set to auto? It should work fine. Also take a look at the back of the thermostat and see if there is three screws, if so loosen the screws and the sub base will come off and the front art of the thermostat will be like the one that you are relacing.
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