I installed 1750 watt stelpro in place of two old baseboard heaters and it blew two different thermostats, what am I doing wrong?

Many Thermostats control by use of 24 Volts AC. Just be sure the Thermostat handles the Voltage AND wattage.
Look Here:
http://www.stelpro.com/web/index.php?action=voir&loc=en-CA&prod=B
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