Indoor-Outdoor Thermometer Question...

Factual Questions
1

I installed a indoor-outdoor thermometer in my truck (92 GMC Sonoma Extended cab) last year. There was a 10 foot wire with a thermister on the end of it. I placed the thermister on a chunk of metal behind my passenger side tire.

Anyway I have noticed that the heat from the engine is effecting the temperature, but the wire was not long enough to place the thermister anywhere else.

So two questions:

  1. Can I add more wire to extend the length, or will that affect the accuracy of the thermister?

  2. Where would a good spot to place the thermister so it wouldn’t be effected by engine or exhaust heat?

MtM

2

Yes, you can add some more wire. Thermistors have a resistance which is normally quite high (~20k Ohms @ 25 [sup]o[/sup]C) relative to the low resistance of the wire. The accuracy won’t be affected enough to matter.

3

I place them in the door jamb at the front of the door. They’re shielded from the sun, engine, and exhaust, but not from outside air. A small hole can be poked in the door weatherstripping to route the wire inside.