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95% + (138)

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High Efficiency Gas Boilers

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Product Image of Ultra 230 - 183,000 BTU Output High Efficiency Boiler - Series 4 (Nat Gas or LP)
$5,265.83 each
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Product Image of Ultra 155 - 123,000 BTU Output High Efficiency Boiler - Series 4 (Nat Gas or LP)
$4,204.00 each
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Product Image of Ultra 105 - 81,000 BTU Output High Efficiency Boiler - Series 4 (Nat Gas or LP)
$3,720.97 each
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Product Image of NRCB199DV 199,000 BTU Combi Boiler (NG)
NRCB199DV 199,000 BTU Combi Boiler (NG)
SKU: NRCB199DV-NG
Noritz
SKU: NRCB199DV-NG
Brand: Noritz
(7)
$3,054.51 each
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Product Image of MFTCW140, 129,000 BTU Output FT Series High Efficiency Wall Mount Combi Boiler (NG/LP)
$3,203.27 each
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Product Image of NRCB199DV 199,000 BTU Combi Boiler (LP)
NRCB199DV 199,000 BTU Combi Boiler (LP)
SKU: NRCB199DV-LP
Noritz
SKU: NRCB199DV-LP
Brand: Noritz
(4)
$3,098.15 each
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Product Image of MFTHW199, 181,000 BTU Output FT Series High Efficiency Wall Mount Heat Only Boiler (NG/LP)
$3,150.90 each
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Product Image of MFTCW199, 181,000 BTU Output FT Series High Efficiency Wall Mount Combi Boiler (NG/LP)
$3,159.99 each
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Product Image of MFTHW100, 93,000 BTU Output FT Series High Efficiency Wall Mount Heat Only Boiler (NG/LP)
$3,039.11 each
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Product Image of 199,000 BTU Noble Fire Tube Combi Boiler (LP)
$3,235.21 each
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Product Image of IP060160C 60,000 BTU Condensing Wall Mounted Combi Boiler (NG/LP)
$2,522.56 each
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Product Image of IP120199C 120,000 BTU Condensing Combi Wall Mounted Boiler (NG/LP)
$3,037.30 each
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Product Image of GV90+4 84,000 BTU High Efficiency Gas Boiler (Nat Gas & LP)
$4,206.13 each
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Product Image of IP090199C 199,000 BTU Condensing Wall Mounted Boiler (NG/LP)
$2,849.00 each
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Product Image of AB-155C AquaBalance Combination Wall Mount Gas Boiler, 125,000 BTU (NG)
$2,666.90 each
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Product Image of AB-80H AquaBalance Heat-Only Wall Mount Gas Boiler, 65,000 BTU (NG)
$2,643.22 each
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Product Image of iP120S 120,000 BTU Condensing Wall Mounted Heat Only Boiler (NG)
$2,271.50 each
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Product Image of ALTA-120B, 97,000 BTU Output High Efficiency High Altitude Boiler (0 to 10,000 Ft.)
$2,556.52 each
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Product Image of IP199199C 199,000 BTU Condensing Wall Mounted Boiler (NG/LP)
$3,500.00 each
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Product Image of IP150S 150,000 BTU Condensing Wall Mounted Heat Only Boiler (NG)
$2,523.50 each
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Product Image of Singular 5200 199,000 BTU Combi Gas-Fired Wall-Hung Condensing Boiler
$3,434.92 each
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Product Image of Singular 4000 155,000 BTU Combi Gas-Fired Wall-Hung Condensing Boiler
$2,236.83 each
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Product Image of iP090S 90,000 BTU Condensing Wall Mounted Heat Only Boiler (NG)
$2,433.31 each
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Product Image of IP060S 60,000 BTU Condensing Wall Mounted Boiler (NG/LP)
$2,203.40 each
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Product Image of MFTHW140, 129,000 BTU Output FT Series High Efficiency Wall Mount Heat Only Boiler (NG/LP)
$2,590.04 each
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Product Image of IP199S 199,000 BTU Condensing Wall Mounted Boiler (NG/LP)
$2,922.50 each
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Product Image of IP150199C 150,000 BTU Condensing Wall Mounted Boiler (NG/LP)
$3,390.80 each
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Product Image of GV90+5 113,000 BTU High Efficiency Gas Boiler (Nat Gas & LP)
$5,163.04 each
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Product Image of ALTAC-136B, 97,000 BTU Output High Efficiency High Altitude Gas Combi Boiler (0 to 10,000 Ft.)
$3,148.80 each
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Product Image of AB-120C AquaBalance Combination Wall Mount Gas Boiler, 97,000 BTU (NG)
$2,533.70 each
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Product Image of 199,000 BTU Noble Fire Tube Combi Boiler (NG)
$3,703.50 each
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Product Image of ALTA-150, 123,000 BTU Output High Efficiency High Altitude Boiler (0 to 10,000 Ft.)
$3,104.53 each
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Product Image of NRCB180DV 180,000 BTU Combi Boiler (LP)
NRCB180DV 180,000 BTU Combi Boiler (LP)
SKU: NRCB180DV-LP
Noritz
SKU: NRCB180DV-LP
Brand: Noritz
(2)
$2,866.54 each
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Product Image of 182,000 BTU Output FT Series High Efficiency, Floor Standing Combi Boiler Fire Tube Boiler (NG or LP)
$5,059.78 each
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Product Image of ALTA-180, 147,000 BTU Output High Efficiency Boiler
ALTA-180, 147,000 BTU Output High Efficiency Boiler
SKU: ALTA-180-1G00
Burnham
SKU: ALTA-180-1G00
Brand: Burnham
(2)
$3,559.59 each
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Product Image of ALTAC-080, 65,000 BTU Output High Efficiency High Altitude Gas Heat Only Boiler (0 to 10,100 Ft.)
$2,692.47 each
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Product Image of 110,000 BTU Noble Fire Tube Combi Boiler (NG)
$3,069.74 each
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Product Image of Ultra 399 - 317,000 BTU Output High Efficiency Boiler - Series 4 (Nat Gas or LP)
$9,624.57 each
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Product Image of ECO Tec Series 2 150-H 121,000 BTU Output Natural Gas Boiler
$3,625.31 each
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Product Image of GV90+6 140,000 BTU High Efficiency Gas Boiler (Nat Gas & LP)
$5,837.29 each
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Product Image of AB-155H AquaBalance Heat-Only Wall Mount Gas Boiler, 125,000 BTU (NG)
$2,718.88 each
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Product Image of 110,000 BTU Noble Fire Tube High Efficiency Boiler (LP)
$2,933.80 each
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Product Image of NRCB180DV 180,000 BTU Combi Boiler (NG)
NRCB180DV 180,000 BTU Combi Boiler (NG)
SKU: NRCB180DV-NG
Noritz
SKU: NRCB180DV-NG
Brand: Noritz
(1)
$2,866.00 each
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Product Image of Simplicity 199 Combination Wall Mount Boiler, 199,000 BTU (NG)
$3,776.86 each
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Product Image of ECO Tec Series 2 110-H 87,000 BTU Output Natural Gas Boiler
$3,697.29 each
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Product Image of 182,000 BTU Output FT Series High Efficiency, Floor Standing Heat Only Fire Tube Boiler (NG or LP)
$4,566.86 each
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Product Image of 89,000 BTU Output Knight High Efficiency Boiler w/ Fire Tube Heat Exchanger (Wall Mount) (NG)
$4,467.80 each
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Product Image of ECO Tec Series 2 199-C 160,000 BTU Output High-Efficiency Residential Condensing Combi Boiler (NG)
ECO Tec Series 2 199-C 160,000 BTU Output High-Efficiency Residential Condensing Combi Boiler (NG)
SKU: 383-900-175
Weil-McLain
SKU: 383-900-175
Brand: Weil-McLain
$4,404.90 each
In Stock
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More About High Efficiency Gas Boilers
Maximize Heat, Minimize Waste.

High-efficiency gas boilers deliver reliable heat while keeping fuel costs in check. Condensing boilers squeeze every BTU from natural gas and propane, pushing AFUE ratings above 90% and cutting fuel costs and emissions without sacrificing performance.

Why Choose a High-Efficiency Gas Boiler
Unlike older boilers, condensing models feature a secondary heat exchanger that captures extra heat from flue gases. That boosts efficiency, reduces return-water temperatures, and cuts energy waste. Over time, savings on utility bills often exceed the investment in a high-efficiency boiler installation.

Natural Gas Boilers vs Propane Gas Boilers
Natural gas boilers offer lower per-BTU fuel costs where utility lines exist. Propane gas boilers bring flexibility for off-grid homes or areas without mains gas. Both fuel types support condensing technology, modulating burners, and outdoor reset controls to keep systems responsive and efficient.

Choosing the Right High-Efficiency Boiler
  • Calculate heat load. Match BTU output to the home’s square footage and insulation levels.
  • Aim for 95% AFUE or higher when possible.
  • Check venting. Condensing boilers need PVC or stainless vent kits for low flue temperatures.
  • Look for modulating burners and outdoor reset controls for peak efficiency.

Installation & Maintenance Tips
  • Pump a condensate neutralizer to protect drains from acidic condensate.
  • Schedule annual tune-ups: clean heat exchangers and check burner performance.
  • Inspect vent pipe seals and PVC connections for leaks.
  • Verify proper combustion air intake in tight, high-efficiency homes.


FAQs about High-Efficiency Gas Boilers

What is a condensing boiler?
A condensing boiler uses a secondary heat exchanger to extract extra heat from flue gases, boosting efficiency and lowering return-water temperatures.


How do I choose between natural gas and propane boilers?
Choose natural gas boilers for lower fuel costs where lines exist. Select propane gas boilers for flexibility in off-grid settings.


What does AFUE mean?
AFUE (Annual Fuel Utilization Efficiency) measures how efficiently a boiler converts fuel into heat over a year. Look for ratings above 90%.


Are there rebates for high-efficiency boiler installation?
Many utility companies and government programs offer rebates or tax credits for boilers with AFUE ratings of 90% or higher. Check local incentives.


How often should I service a high-efficiency boiler?
Annual maintenance is recommended: clean heat exchangers, inspect burners, and verify proper venting to maintain peak performance.