Measuring the output of a phase control triac
A triac (and snubber circuit, if present) will leak a certain amount of current, so it's not realistic to measure the output without a load. 

The best way to test the output is with the motor connected as a load. If the voltage measured across the motor is not more than zero, measured on the AC VOLTS range of any multimeter, it's not going to turn. It's rare that a triac fails in the open state, normally they'll fail "on" and you'll get full RPM.