I'm sorry, mistaken and explained wrong in my previous post about coolant being used in vaporizer
Vaporizer uses the engine coolant to vaporize the LPG in liquid state to gas. Also it reduces the pressure.
Using gas kit will not affect the engine temperature (there will be effects, but negligible)
What is a Vaporizer ?? Is it a separate cooling unit for the GAS kit ??
I too was thinking that if the engine gets hot due to use of gas kit the thermostat will keep the radiator on for more time till engine cools.