I'm only 2 days old with Pi but had the same problem with a 21" LED monitor. I left the vga plug in while connecting the Pi with the HDML thru a dongle to a DVI socket on the monitor. Tried booting the Pi 3 or 4 times and not a flicker from the monitor. Reached around the back to pull the vga plug and the screen lit up with NOOBS waiting.
If there are any other video jacks plugged into the TV try removing them. If that's not the case and you've selected the proper input on the TV then I'm stumped.
Bad things happen to good people to balance the good things that happen to bad people.