Heater fuse problem

[cam.man67]

So here's the problem: Last week the heater switch in my truck went bad. All right, no problem, got it ordered from ECE, delivered today. I put the thing in, got a new fuse (in my haste to take the old one out I blew a fuse when the hot wire connected with the dash) everything works fine. For about a minute. Then the fuse blows again. I know the PO rewired the cig lighter so it pulled off the heater fuse, so I unplug my GPS unit, put another fuse in, and the heater works fine. And then it blows again.

Long story short, I don't know what to think. According to the fuse box, that should be a 10 amp fuse, which is what I put in. I haven't changed the wiring in any way, so I can't figure out what could have possibly changed. Suggestions?

I'm tempted at this point to put a 25 amp fuse in and be done with it. Any reason I shouldn't do that?


Thanks in advance!