Thermador 5 burner cooktop. One burner did not ignite so we hired tech to repair. Tech unable to remove four of five venturi's from jet holder (threads frozen). I tried to remove and crimped/broke gas line to one burner. I ordered gas line from your company today. The non-igniting burner problem manifested itself in following way. When knob turned on igniter did not spark or click, no noise at all, however gas was coming out of jet. What part should repair that problem. Also I have been told that in order to remove stove top from base to attempt repair, I must first remove regulator and bracket holding pipe regulator screws into to, from base and then drill out all screws holding other parts to base. I should then be able to remove top from base. I would appreciate feedback/suggestions on this plan of action. Thanks in advance for any help in this regard.