You can either pull warm air through your filter, or push warm air through your filter. no matter how it is done, warm air will be going through your filter. So most likely someone gave you advice who did not know what he was talking about. But myabe I do not understand totally what you are saying also.

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This is all just a figment of my imagination... If this had been a Real Emergency, I would have told you where to go.

Everything I say on these forums is completely fictional and only used to make myself look Cool. Photos are pasted from intercepted ALIEN transmissions.