Hello The LF error code is a indication of a long Fill error..Which means the computer senses a problem with the amount of water that is filling into the washer...When you do see the water filling..Is it a good steady flow ..?
The intial few second fill of water from the right side is a good flow when I attempt a hot/cold cycle or cold/cold cycle. After this initial brief flow, the washer attempts to fill from the nossle in the center back of the mashine. No water is comming out on this cycle. The machine hums for a while and then the LF code comes on.
This is something that sounds like I might make things worse if I try to do it myself.
When I call the repair service that I normally use, I will tell them that I think it is an inlet valve base on the information you provided. Are they likely to have that part on their truck or will they come, diagnose the problem and have to come back with that part? I do not know if they order a part and it turns out not to be needed whether the can return it.