According to the Comcast Customer Service Guarantee you shouldn't have to pay for the tech visit "for faulty equipment and poor workmanship on Comcast's part". Call Comcast, use Billing option. Have the following page open and read number 3 to the person you speak with. Tell that person to remove the charge.
http://www.comcast.com/Corporate/Customers/CustomerGuarantee.html?SCRedirect=true
We will resolve routine issues in one visit or we'll credit you $20 or give you a free premium channel for three months.
After the first visit to your home, if we do not satisfactorily complete installation or can’t resolve a routine issue, we will credit you $20 or give you a free premium channel for three months. Additionally, we won’t charge you for a service visit that results from a Comcast equipment or network problem.
Comcast employees must be authorized to post in the forum. Employees posting here have their names in red and are designated as employees. Names not in red are customers.
