LAARS 50 Gal. Indirect-Fired Water Heater, Residential, Stainless Steel, Single Wall

Laars-Stor LS-SS-50-L – 50-Gallon Indirect Water Heater for Hydronic Systems

The Laars-Stor LS-SS-50-L is a 50-gallon indirect-fired water heater engineered for high-demand residential and light commercial hot water applications. Utilizing a 135,000 BTU/h single-wall, stainless steel heat exchanger and premium-grade Type 444 stainless steel tank construction, this unit offers excellent thermal transfer, corrosion resistance, and long service life.

Capable of delivering up to 237 gallons in the first hour and sustaining 209 gallons per hour at 135 MBH input, the LS-SS-50-L is well-suited for hydronic heating systems requiring high-volume hot water output with low standby losses. Its foam insulation and compact footprint make it efficient and install-friendly in space-constrained mechanical rooms.

Key Performance Features

• High First Hour Delivery: Rated for 237 GPH @ 135,000 BTU/h input, supporting multiple simultaneous demands.
• Corrosion-Resistant Construction: Fabricated from Type 444 stainless steel to resist pitting and chloride-induced stress corrosion cracking.
• Adjustable Immersion Aquastat: Factory-installed Honeywell control allows field adjustment between 80°F and 160°F for system optimization.
• Non-CFC Foam Insulation: 2" thick foam minimizes standby heat loss and improves thermal retention.
• Enhanced Inlet Diffuser: Factory-installed sediment-reducing inlet tube maximizes usable hot water draw and reduces thermal layering.

Technical Specifications

• Storage Volume: 50 gallons
• First Hour Delivery: 237 gallons
• Continuous Flow: 209 GPH
• Max Heat Input: 135,000 BTU/h
• Tank Material: Type 444 Stainless Steel
• Coil Material: Stainless Steel Single-Wall
• Connection Size: 1" NPT (boiler in/out); 3/4" NPT (domestic in/out)
• Relief Valve: Factory-installed T&P valve

Installation and Service Considerations

Installation should be completed by a licensed plumbing or hydronic heating contractor to ensure code compliance and system integration. The unit is designed for vertical floor-mount installation. Proper boiler-side flow and circulation are required to meet rated recovery rates. The low-restriction drain valve simplifies periodic maintenance and flushing procedures.

Contractor Advantages

• Drop-In Ready: Pre-installed aquastat, T&P valve, and diffuser tube reduce labor time on-site.
• Universal Application: Compatible with most closed-loop hydronic systems, including gas, oil, or modulating-condensing boilers.
• High Output in Compact Design: Ideal for space-sensitive installations that require high domestic output without added gas appliances.

Warranty

• Tank and Heat Exchanger: Limited Lifetime Warranty (residential applications)
• Component Warranty: 1 Year (parts and controls)