The error indicates a signal issue to your TV outlet. Unless you have recently made changes to your splitters or wiring, you should get a tech out. The tech will find and fix the marginal signal issue which can be the drop, loose / wet / corrorded fittings or even upstream into Comcast's RF portion of the plant.
A refresh signal will not help and is not available online to everyone, since these systems are not the same across the US.
In my area sending a reset signal is one of the phone tree options when you call 1-800-Comcast. But, as Jay says, "one moment please" suggest a signal problem, and for those a reset signal is not likely to be helpful.
Yet again comcast experts you did not even read the posters question. It was a simple yes or no answer if we can send a refresh signal to a TV without live interaction. So can we do this either with a smart phone app or from online line? Simple question.
As Jay stated "A refresh signal will not help and is not available online to everyone, since these systems are not the same across the US".
It's also possible that the feature to do it online does not exist. I've done a search and can find nothing that indicates it is possible.
Comcast employees must be authorized to post in the forum in an official capacity. Employees posting here have their names in red and are designated as employees. Names not in red are customers.
This is done to protect customers and for assurance that they are dealing with a Comcast employee. Non-Authorized Employees are allowed to post but cannot state they are employees nor can they allude to being employees.