Monitor Condenser Boilers for Commercial Installation Nelson & Small Energy Solutions
Serving New England and Upstate New York
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Monitor condensing boilers are the most efficient, versatile, low-cost, low-maintenance heat sources available. These ultra-efficient commercial and residential boilers are so much more cost effective than other gas furnaces or oil furnaces that they often pay for themselves in as little as 3 years.
Several Monitor MZ40C units can be linked together to economically produce up to 1 million BTUs, enough for small apartment buildings, restaurants, car washes and other commercial buildings.
"Ecurb Properties in Minneapolis, Minnesota recently converted 5 buildings to MZ40s and have experienced a 60 to 70% savings in the first few bills!"
Ecurb Properties, Bruce Johnson, owner
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Products
Monitor MZ Propane and Natural Gas-Fired Condensing Boilers
 Monitor MZ Propane and Natural Gas-Fired Condensing Boilers
More details: Installation and venting options

  • Provides heat and hot water simultaneously on 2 completely separate water supplies
  • Ideal for radiant floor heating
  • Uses propane or natural gas
  • AFUE efficiency 92% to 97%
  • 15 year warranty on heat exchanger
  • Typical payback: Unit often pays for itself in as little as 3 years
  • Completely self-contained system means minimal plumbing installation cost compared to conventional boiler
  • Manufacturer suggested list price as low as $3,600 plus installation (will vary depending on plumbing and venting options): See your dealer for details.


MODEL Model MZ25C Model MZ40C Model MZ25S
This unit easily heats most homes and can produce an endless supply of hot water when combined with one of our storage tanks. This model has the highest output of the Monitor line and is perfect for larger homes and commercial applications. Units can be linked together to efficiently produce up to 1 million BTUs. This model combines heat and domestic hot water and is perfect for one-bathroom homes or condos where space is at a premium.
BTU Input 94,500 71,000 / 142,000 94,500
AFUE Efficiency 92 to 97% (depending on return water temp.) 92 to 97% (depending on return water temp.) 92 to 97% (depending on return water temp.)
Built-in Controls & Functions Priority pumped hi-temp circuit (for DHW or heat) Priority pumped hi-temp circuit (for DHW or heat) Integral DHW tank with separate aquastat
Dimensions 30"H x 22"W x 13"D 30"H x 22"W x 13"D 30"H x 22"W x 13"D
Weight 125 lbs 160 lbs 160 lbs
Vent Length Vent runs longer than 13.5 feet derate input by 1% per 30 feet. Contact MPI if run is to exceed 100 feet
Fuel Each MZ is factory tuned for natural gas, but propane kit is included. Conversion takes about 15 minutes.


BS Series Stainless Indirect DHW Storage Tanks
 BS Series Stainless Indirect DHW Storage Tanks
The Monitor BS Series of stainless domestic hot-water storage tanks are among the world's finest. Since the tank does not actually heat the water (the boiler does), the actual efficiency will be dependent upon the efficiency of the boiler. When the boiler used is our MZ that efficiency should be in the 90% plus range. Traditional vented domestic hot water heaters are rated at only 50% to 60%.

The Monitor BS Tanks are so well insulated that the stand by heat loss is 1/2° in 2 hours. They are designed for installation with the MZ gas fired units (as well as for the FCX for residential use) and are virtually immune to scale and lime buildup. The pleasing design and exceptional finish make them at home in world-class applications of all types.

Technical Specifications
Models BS 25 BS 40 BS 50 BS 80
Nominal Storage Gal. 25 40 50 80
Height IN. 27.5" 36.4" 45.3" 63"
Diameter IN. 23.6" 23.6" 23.6" 23.6"
All Pipe Connections MPT 3/4" 3/4" 3/4" 3/4"
Mac DHW Pressure PSI 100 100 100 100
Aquastat Range F 68-176°F 68-176°F 68-176°F 68-176°F
Aquastat Differential F 10.8°F 10.8°F 10.8°F 10.8°F
Inspection Port Opening IN. 3.9" 3.9" 3.9" 3.9"
Nominal Exchanger Power (170°F Av. Boiler Water Temp.) MBH 115 115 200 210
Nominal Reheat Time form 50°F to 140°F Stored MIN. 10 15 12 17
Continuous output at 110°F GPM 3.8 3.8 6.5 6.7
Nominal First Hour Draw at 70°F GAL. 250 260 430 465
Dry Weight LBS. 71 86 121 159
Ratings assume cold-water inlet at 50°F, boiler circuit average temp of 170°F and boiler output at least equal to the nominal heat exchanger power shown above.



 How it works
  • Air drawn into boiler from outside — pre-warmed by outgoing exhaust
  • Mixed with fuel (LP, gas or oil)
  • 2 stage heat exchanger system produces hot water within seconds
  • Reaches full temperature and efficiency in less than 90 seconds — traditional boilers take 10 minutes or more
  • Heated water pumped out through plumbing
  • Sealed combustion exhaust vented back out of house
  • All heat is captured inside building — No heat waste up chimney
Benefits
  • Uses 30%-70% less fuel
  • Virtually silent operation
  • Lowest-emission, cleanest-burning boiler on market — exceeds strictest air quality standards by 60%
  • Highly versatile — replaces and greatly improves upon almost any other heating system
  • Great for radiant floor heating, baseboard, forced hot air, radiant wall panels, domestic hot water, snowmelt, and many other applications