[vlieneke]

Dryer was heating well one day and next day no heat. air flow is clear and everything else works. just no heat. would this be the fuse or the element?

[denman]

Here are your parts
Replacement parts for WHIRLPOOL RES7745RQ0 | AppliancePartsPros.com

And here is the wiring diagram
https://www.servicematters.com/docs/...%208528190.pdf

Best way is to check components with a meter.

One way to lessen the odds is:
Put the unit into timed dry, if timer does not advance you may have lost your 220 volts.
IF OK
Then put the unit into an Auto cycle, if timer does not advance then odds are high that the heater is blown since the timer gets it's voltage through the heating element in this mode.
IF No Good (no timer advance)
Then could be the thermal fuse or a thermostat.
Unplug the unit, short the two wires to the thermal fuse together, taping them up so they cannot short to the frame, plug the machine in and give it a try. If it runs with heat you know it is the fuse. Replace ASAP as this is a safety device and the unit should not be operated without it.

If the fuse is blown clean and check your vent system, it is often the cause of a blown fuse.