this Penn A421 electronic control provides advanced features like anti-short cycle delay and sensor offset to protect compressors and optimize system cycling

it is a clear indicator of a restriction

2 1/2" ASME Four Hole Flange

This kit is the specific McDonnell & Miller 421-30 replacement part for any Series 25A

providing critical protection for high-demand steam boiler systems

Trane VAL19951 TXV 321042-401 this Penn A421 electronic controlThe Trane VAL19951 is a commercial grade 6 ton R410A TXV engineered for precise refrigerant metering in high capacity cooling systems. This thermostatic expansion valve features a 3 8" x 1 2" connection size with ODF solder fittings, ensuring a secure, leak free integration into the liquid line. Designed specifically for R410A refrigerant, it maintains the ideal superheat balance across the evaporator coil to prevent liquid slugging and protect the