Spitiful renewal

So this trait works ONLY for healingslot skill? Cannot be procs by Wells or signet od locust,..?Ty

It says only healing skill, not every skill that heals you. I'd suggest checking wiki for small questions like this one, it can clarify some things.

I'm just wondering why ICD's there(5sec), if the lowest CD for healing spell is 20sec.Passive Vampire proc this? Minion? ??

According to wiki it had different functionality which needed to have ICD. Since gw2 is based on spaghetti code, some things are better when you dont change them. For example, some traits state that they proc 100% of the time, it was easier to change the number than to remove the part of trait.

@"Catchyfx.5768" said:I'm just wondering why ICD's there(5sec), if the lowest CD for healing spell is 20sec.Passive Vampire proc this? Minion? ??

The ICD is relevant because of Summon Blood Fiend. Both summoning and sacrificing the minion count as "using a heal skill." Since there's no cooldown in between those, you could almost immedietly double-proc this trait.

Now, would that be broken? Heck no. That's 2.5 seconds cast time for some mediocre healing without additional effects. Adding on 2 conditions cleanses (1 second apart) with an additional ~1600 health would maybe make it almost reasonable to do. Buuut, if you're running Blood Fiend, it means you're a minion setup on traits, and will get far better condition management and healing by just leaving the Fiend up to do its thing. Or you're in raids and don't care about using your heal skill for recovery/condition management anyway.