There is no heat on unit and someone suggested my smart valve needs to be replaced? Is that true?

I don't know if yours is bad with out testing it. The Smart Valves have a small control board with very weak solder joints where the four wire harness plugs into it. It can be re-soldered but I would not recommend tampering with a gas valve without full knowledge of the workings of that valve. On the other hand, Smart Valves are a lot more expensive than other gas valves.

There is also a small 24 volt ignitor that could be burnt out. If it is burnt out you can see the break in the element. That would be the cheaper of the two to replace

there is no heat on unit and someone suggested my smart valve needs to be replaced? Is that true?
It is a Federal violation to open or alter a gas valve, it is very dangerous so don't do it. Smart valves are expensive pieces of junk, but mabe that's just my opinion, but I don't think so. :-)