Thanks Roberto.
I have other lines with other rules and the screener works properly, as soon as I add the volume one I always get 0 as result, but not an error.
Without the lines regards the volume it works.
This is the full code, which now shows 0:
indicator1, ignored = CALL “Engulfing Istogramma”
c1 = (indicator1[1] > 0)
indicator2 = ExponentialAverage[10](close)
indicator3 = ExponentialAverage[20](close)
c2 = (indicator2[1] > indicator3[1])
indicator4 = ExponentialAverage[20](close)
indicator5 = ExponentialAverage[50](close)
c3 = (indicator4[1] > indicator5[1])
indicator6 = AverageTrueRange[20](close)
c4 = (indicator6[1] > indicator6[2])
indicator7 = Volume
indicator8 = Average[20](Volume)*1.5
c5 = (indicator7[1] > indicator8[1])
SCREENER[c1 AND c2 AND c3 AND c4 AND c5] (Variation AS “% Var barra prec”)