ressure Ranges, psi Pressure Ranges, inches wc Approvals Pipe Ambient Temperature Enclosure Type Contact Ratings Not Applicable 1/4" – 18 NPTb 32˚ to 150˚ F NEMA 1 24Vdc / 24Vac Control Circuit Adjustable subtractive differential CSA, UL 1/4" – 18 NPTb Maximum 150˚ F NEMA 1 120Vac: 8FLA, 48LRA 240Vac: 5FLA, 30LRA Not Applicable CSA, UL 1/4" – 18 NPT Maximum 150˚ F NEMA 1 120Vac: 9FLA, 58LRA 240Vac: 5FLA, 29LRA CSA, UL, FM, CSD-1, FCC 1/2" – 14 NPT 32˚ to 140˚ F NEMA 1 120Vac, 50/