Will this fit a Series 157S low water cut-off

This seal is designed for 2/1-4"-12 thread Rotalock connections

It is the direct replacement for part number 511-546-920 and is commonly specified for high-efficiency units like the Weil McLain Ultra and ECO Tec series

Concealed Adjustment

Weil Mclain 383-500-600 Sensor Kit Els PW 17895 Will this fit a SeriesThe Weil McLain 383 500 600 Flue Temperature Sensor Kit is a critical monitoring component designed specifically for Ultra Series 3 and Commercial gas boilers. This OEM replacement kit includes a high accuracy dual sensor and a fresh sealing grommet to ensure airtight installation in the stainless steel vent pipe. As a veteran technician knows, maintaining precise exhaust thermal data is non negotiable for boiler safety and efficiency. This sensor