It's a surfactant, which means it allows water to coat surfaces better, especially the rough ones inside an engine. It won't change the temp sensor readings, but will provide somewhat better heat transfer when that T-stat is fully open and the coolant temp is climbing. 

Stuart

-----Original Message-----
From: Vanagon Mailing List [mailto:vanagon@gerry.vanagon.com] On Behalf Of Dan N
Sent: Sunday, July 12, 2015 11:22 AM
To: vanagon@GERRY.VANAGON.COM
Subject: Water Wetter questions...

hi all,

I plan to add a bottle or 2 of Water Wetter to my van..

according to what I know (from the web)... Water Wetter helps to better dissipate heat in the cooling system...

but... the question is...

would Water Wetter (or any similar product) affect the Temp2 sensor reading on our vanagon...

would our vanagon run richer or differently because it may run cooler?

could you please give some thoughts about using this product?

thanks

dan