I am using the Thermostat template in the new dashboard with the Generic Z-Wave Thermostat type. When using the mode button on the template, all of the options other than 'auto' give an error similar to this:
dev:392019-03-25 07:17:15.303 pm debug' cool' is not a valid thermostat mode
dev:392019-03-25 07:17:15.298 pm debugsetThermostatMode( cool) was called
Notice the extra space before cool that is not seen when setting auto.
There are similar issues with fan mode as well.
I can go to the device page and click the cool button there and it works as expected, so it looks like a small issue in the template. Maybe?