Customize Your Toyotomi 128 Hydronic Heater

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2. Explore available options.
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Status: In Stock

Hydronic Heater

Toyotomi 128 Hydronic Heater (US$2,409.00)
Venting Option

Toyotomi Chimney Installation Adapter Kit (4 In.) (US$139.00)
Toyotomi Chimney Installation Adapter Kit (US$139.00)
Toyotomi Direct-Vent Flue Pipe Installation Kit (US$375.00)

Toyotomi Flue Pipe Extension (US$206.99)
Toyotomi Extension Pipe Set (US$169.99)
Toyotomi Extension Pipe Kit 31.75" To 57" (US$400.99)

Ergomax, Heat Exchanger, E23 (US$2,699.00)
Fuel Filter #496 1" FPT (US$90.99)
Fuel Filter Fittings Kit (US$40.99)
Fuel Tank Valve Kit (US$78.99)
Water Heater Scale Prevention System, 3/4" (US$130.99)
Main Item Price US$ 0.00
Optional Item Price US$ 0.00
Price for this Configuration US$ 0.00



The OM-128HH Toyotomi On-Demand oil Hydronic Heater is the perfect solution for those seeking a compact and efficient heating system. With an 87% AFUE efficiency, this low-mass water heater can save customers as much or more than the leading cast iron boilers, all at half the size. The stainless steel heat exchanger and cold start capabilities ensure consistent performance and fuel savings of up to 50%.

The on-demand system also means there is no need for costly storage of hot water, and with ETL and CETL home and mobile home approved safety features, you can have peace of mind. The direct vent or chimney vent option adds to the versatility of the product, making it easy to install and operate.

At only 77 lbs, this hydronic heater is lightweight enough for one-person installation, making it ideal for residential or commercial use. And with a limited 10-year warranty, you can be confident in the quality and longevity of the product. Upgrade your heating system with the OM-128HH Toyotomi On-Demand Hydronic Heater and enjoy a new level of comfort and efficiency.

Required Accessories:

Requires the addition of one of (A) required accessories to complete the unit


  • 20476415 Chimney Vent Installation Kit
  • 20476430 Chimney Vent Installation Kit
  • 20476440 Direct Vent Installation Kit



  • Economical: Some consumers have experienced fuel savings of up to 50%!
  • No costly storage of hot water when it is not needed…Cold start capabilities!
  • Stainless steel heat exchanger!
  • 87.1% efficient!
  • Proven trouble-free performance
  • Safe: ETL and CETL home and mobile home approved
  • Direct vent or chimney vent!
  • Small, compact size
  • 77 lb. weight allows one person installation
  • Limited 10 YEAR WARRANTY





Type combustion type – oil pressure vapor
flue pipe – forced flue/chimney vent
heating system – on-demand
purpose – hydronic heating(1)
Ignition high voltage discharge spark
Fuel Type: ASTM D3699 K1 keroseneEROSENE
ASTM D396 no.1 low sulfur fuel oil
ASTM D975 ultra low sulfur heating oil/ diesel
ASTM D396 no.2 fuel oil (home heating oil)
Efficiency 87.1%
Hot Water Input 148,000 btu/h
Hot Water Output 128,900 btu/h
Fuel Consumption 1.05 gal./h
Max. Hot Water Temperature 176°F (approximately)
Water Flow Rate/
Temperature Rise:
6.2 gal./min. (40°F rise)
4.1 gal./min. (60°F rise)
3.1 gal./min. (80°F rise)
Capacity of Heat Exchanger 5.10 gal.
Fuel System external tank(2) gravity fed
Dimensions (W x H x D) 12-5/8" x 27-3/4" x 22-1/2"
Weight 77 lbs. empty
Vent Pipe Hole 4-3/4" diameter
Max. Length of Vent Pipe 10 ft., 3 bends or less
Electric Rating 120 volts AC, 60 Hz
ignition - 120W
burning - 98W
Required Accessories fuel filter, flue pipe installation kit (Part #20476440) or chimney installation adapter kit (part#20476430 - 5 inch kit or #20476415 - 4 inch kit)
Safety Device over-heat protector,ignition safety device, heat exchanger bi-metal switch, dual-temperature fuse, fusible link valve
Exhaust Air Temperature less than 500°F
Nozzle quantity of vapor - 0.85 GPH
spraying angle - 60°
spray pattern: delavan type XA
Temperature Fuse 282° F
Electric Current Fuse 5A,
7A (for external circulation pump or accessory)


(1) Check state andlocal codes/ordinances for permitted use. Can also supply domestic hot water provided it is used with indirect storage tank.
(2) External tank to be purchased from local suppliers.



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