Resideo - Honeywell Home L4081B1047 Aquastat Controller

The Aquastat Controller L4081B1047 from Resideo Honeywell Home delivers precise temperature control for gas/oil-fired hydronic heating systems. This horizontal immersion controller combines high-limit protection with a flexible low-limit setting to keep boilers safe, efficient, and responsive. With a high-limit range of 130–240°F and a low-limit range of 110–220°F, it adapts to varying boiler loads while the fixed high-limit differential ensures reliable shutoff. This model is designed for horizontal immersion and supports well-spud connections for flexible installation.

• SPST contact configuration for simple on/off control of boiler circuits.
• Adjustable low-limit differential from 10 to 25°F, with a fixed 10°F high-limit differential.
• 1/2 in conduit connection and a well-mounted design for straightforward installation.
• UL and CSA approvals ensure safety and compatibility with standard equipment.
• Wide temperature ranges with high-limit 130–240°F, low-limit 110–220°F, and sensing element up to 265°F.
• Compact dimensions 4-1/8"W x 2-3/4"D x 3-7/8"H for easy retrofit.

Ideal for professionals seeking a durable, UL/CSA-approved aquastat with precise control and broad compatibility across gas/oil-fired hydronic systems.