Indirect water heaters are beneficial where residential and commercial applications have extensive demands for domestic (potable) hot water. Alliance™ SST, LT and SL indirect-fired water heaters meet the need for domestic hot water with unique designs and uncompromising reliability. The Alliance indirect hot water tanks are available in a variety of sizes and materials depending on water quality and hot water demands.
How They Work
Cold domestic water entering the tank is heated as it is diffused across the surface of a uniquely designed heating coil. This heating coil contains hot water circulated by the boiler. An external control monitors tank water temperature for comfort and efficiency. See Figure 1.
Indirect vs. Conventional Direct-Fired
All “tank” water heaters store hot water to be used for household needs. A conventional direct-fired tank uses a 34,000 BTU heat source. By comparison, a similar indirect tank uses over 100,000 BTUs of boiler power! With its vastly greater heating capacity, an indirect water heater can actually create hot water faster than it leaves the tank. Your supply of hot water is virtually limitless!
Figure 1
Indirect Water Heater Models
Alliance™ SST
Stainless Steel Indirect Water Heater
- Passivated stainless steel tank for long life and corrosion resistance
- Smooth surface stainless steel coil resists scale buildup and speeds hot water recovery
- 8-year leak-free warranty, upgradeable to lifetime warranty at no charge
- Lighter weight and installation-friendly design with adjustable feet on models 30-75
Alliance™ LT
Thermoplastic-Lined Indirect Water Heater
- Thermoplastic liner: resistant to rust/corrosion; ideal for most water conditions
- No anode rod required—reduces maintenance costs
- 10-year with optional lifetime warranty
- Lighter weight compared to SL—easier handling and installation
- Extremely low standby loss (<0.8°F/hr)
Alliance™ SL
Hydrastone-Lined Indirect Water Heater
- Hydrastone lining provides exceptional longevity in acidic, hard or otherwise aggressive water environments
- Minimal maintenance; no anode required
- 10-year with optional lifetime warranty