It works well at temperatures, say in the 20°F range, but as it gets colder it seems to slow down the melt rate. (not unexpected). I upgraded to the new Davis rain cone, and found that I needed to remove the debris screen. It was holding the snow and preventing melting.
Search the forum for "
YARCH"*. The post for March 22, 2014 is the one showing the heater. I was not able to find the same bimetal thermostat that Davis uses. Mine is a 60°F open, whereas I think Davis' is hotter:
The heater assembly includes a thermostat switch. If the temperature at the thermostat reaches 110°F (43°C) the thermostat will interrupt power to the heater element.
I am not sure if this is really necessary in order to melt the snow. The 60°F seems to work fine. If you can find a higher temperature switch, it might help.
*"
Yet
Another
Rain
Collector
Heater"

Greg H.