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Outdoor Coal Boilers Products

The S130 Coal Gun outdoor boiler is perfect for those looking to save time and money! The efficient Coal Gun Outdoor can pay for itself in as little as two years. A hopper holding nearly 2,000 lbs of coal and the fully automated feed and ash dump system means minimal maintenance. For more sizes… Click here

This can give you a 30 day burn time depending on demand! The Coal Gun

uses Pennsylvania’s locally mined anthracite fuel and can provide heat for an entire home including domestic hot water for about 70% less cost than electric and nearly 50% less cost than conventional oil or gas systems.
The outdoor housing can be custom designed to match the exterior color of the user’s home or outbuilding. Call today for more information!

Every AHS Coal Gun is manufactured from the highest quality materials by highly trained, dedicated technicians. Every unit is tested extensively before it leaves our factory to ensure its adherence to our high standards of quality. In fact, we guarantee that our product is free from defects in materials and workmanship*. Each AHS Coal Gun comes complete with all controls necessary for operation and safety. Standard equipment includes an insulated boiler jacket, totally enclosed motor and drive systems, primary and backup aquastat thermostats, thermo ash-monitoring control and pressure relief valve.

Our Coal Gun boilers are some of the most durable heating units available. The AHS commitment to quality leads to a long boiler life (some reported at 30 years and counting) and years of hassle-free operation. The bottom line is that a quality-manufactured AHS Coal Gun will save you both time and money in your heating application.

How It Works…

Pea or buckwheat sized anthracite coal is transferred to the coal pot through the gravity feed hopper. An induced draft fan pulls air through the barrel enhancing combustion of the coal. The hot exhaust gasses then spin through our unique swirl chamber heat exchanger and into the cyclone separator where any fly ash is removed. Anthracite coal does not create creosote or give off any smoke!

Fuel Consumption…

The amount of fuel used depends on a great many factors, including the weather, type of installation, and building construction. Due to its high efficiency, however, the AHS Coal Gun uses less fuel than other units on the market and will substantially reduce your annual heating costs.

Thermo Ash-Monitoring Control…

All Coal Gun® boilers feature a Thermo Ash-Monitoring Control which provides optimal use of your fuel. Ash that contains fuel that is not fully combusted will be a higher temperature than ash coming from thoroughly combusted fuel. The Thermo Ash-Monitoring Control automatically monitors the temperature of the ash leaving the coal pot and leaves the ash in place until complete combustion occurs before allowing it to fall away. No adjustment from the factory setting is typically necessary to have the boiler perform at peak power output throughout the burn season (a minor on-site adjustment may be necessary when the boiler is first installed). With the Thermo Ash-Monitoring controlled grate, it is possible for the fire to remain lit for days during low use periods.

*Limited Warranty

Alternate Heating Systems boilers and furnaces are warranted against defects in materials and workmanship for the following periods:

  • Boiler Vessel – 20 years
  • Grate S130/S260 -Lifetime
  • All other components both manufactured by Alternate
    Heating Systems and purchased from vendors will
    vary in length of warranty from 30 days to 1 year

A copy of the complete warranty text, detailing coverage, limitations, warranty claim procedure and state law rights is available from Alternate Heating Systems.

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  • Smoke Free
  • Outdoor Use
  • Large Hopper
  • Minimal Maintenance
  • Cost Effective
  • 83% Efficient
  • Versatile Applications
  • Lifetime Durability

Call (717) 987-0099 for pricing

Assembled Specifications



Heating Capacity* (sqft)


Approximate Water Capacity (gal)


Width (in)


Height (in)


Length (in)


Approximate Weight (lbs)


Flue Size (in)


Return Tapping (NPT) (in)

(2) 1 1/2

Supply Tapping (NPT) (in)

1 1/2

Hopper Capacity

2,000 lbs


Wood Siding 

Our standard siding is ribbed sheet metal, we offer the “board and batten” look as an option.


Domestic Coil

This Domestic Coil features a 100° F rise at 5 gallons per minute, 50° water inlet temperature and 65 PSI water pressure. It is threaded into a 4 IN NPT threaded fitting provided on the boiler for this purpose.

ASME Certification

The ASME Certification guarantees the steel grade and weld quality of the boiler water jacket. Each ASME Certified water jacket has been pressure tested to 60 PSI, and includes a 30 PSI release valve. This certification is required for all commercial installations. The certification is also required for some residential installations depending upon local codes – it is up to the homeowner to determine the need for an ASME
certification on any boiler purchased.

Low Water Cutoff

Senses the water level in the vessel and shuts the unit down if the water level falls to an unsafe condition.