Forum Discussion

zoro4's avatar
zoro4
Explorer
Sep 20, 2013

Aftermarket water temp gauge reads low due to wire length

I'm working on a rear engine RV and installed a new water temp gauge and I noticed it's reading low by atleast 10*F. Called the gauge supplier and they assure me it's due to the long wire length but t...
Class A
Daveinet's avatar
Daveinet
Explorer
Sep 20, 2013
Time for a reality check. The resistance at normal operating temp (200 degrees) is around 1K ohms. 18 gauge wire resistance per foot is around .5 ohms per 100 FEET ! A 10 degree difference is a about 100 ohms change. A poor connection could cause the problem, but not the wire gauge.

I should also ad that you could see some difference as a result of where the 2 sensors are mounted. Otherwise, I would suggest the sensor is probably off.

About Motorhome Group

38,707 PostsLatest Activity: Feb 28, 2025