I am installing new goodman heat pump... 7 wires... followed directions on the thermostat instructions but had a blue wire left over... so screwed it into the B screw without checking goodman data... unit did not come on... I realize now that blue wire is the common... if I had it wired and powered like this for few minutes... do you think I blew a control board or something... I have an ac installer coming this weekend to finish the install since I am having some medical problems and can't get under house to attach ductwork...

Alan

You should be OK but you may have blown a fuse or transformer if you powered it up with the thermostat set to heat. B on the thermostat is 24v hot all the time in heating mode(made to energise the reversing valve in heat mode). You had 24v common that would make it a direct short.