Organ/Harmonium/Pedal Piano
He wrote 42 of these pieces from 1850-1884.
The seem to all have a religious themes. They are in German and Latin and are often based off of other composer’s work.
He wrote 3 pieces for organ with other instruments. Two for organ and trombone, One for organ trombone and violin.
They are:
F1 679410 828 Aria ‘Cujus animam’ aus dem Stabat Mater von Rossini, org, trbnc1860–70UE viiided. C.E. Grosse; not rel. to A141/1; see K5
F2 677 409 848/1,2 Hosannah (Alleluja del Cantico del Sol), org, trbn ad lib1862–3Weimar: Kühn, 1867†EMB ii, UE viiiI8, 1st version
F3 678 411a 100 6–7 Aus der Ungarischen Krönungsmesse, vn, org/hmn: 1 Offertorium, 2 Benedictus1871Leipzig: Schuberth, 1871†; 1873UE viiiarr. from I9; the order here reflects the liturgical sequence, as in the 1st edn; see also A238, B31, D10, E23, H14

This is information is from the Oxford Online article on Franz Liszt