Anytime it's heating, it will draw the same amount of current. 10ga wire minimum.
Your guide shows a 1P 30a breaker for the 220v 06 model. You don't have 220v on a 1-Pole breaker.
The guide is a little misleading. Europe. You can;t get 220v on one phase using the neutral at your house.
You would have to wire 1 Line directly hot instead of the neutral. Don't do it.
Baseboard heaters were allowed to do that in the sixties.
NEC put a stop to that bullshit.
Neither the 04 and 06 have a thermostat. You need to rethink this application.
If you have 10ga wire in the wall, connect one Line to a 30A 1P breaker, one line to neutral for 120v.
Since you don't have temp control, you can do the mixing valve thing or buy one with a thermostat.
Bill, don't run it anymore until this is corrected.
The 220V 1ph is Europe. That can be confusing.
In the U.S., and in fact everywhere in North America, the standard voltage is 110 V (with a frequency of 60 Hz) rather than the 220 volts used in Europe. The 06 model will not help your situation.