Nti tx51a Trinity Modulating Boiler 46 Mbh 93%

Product Description

The NTI tx51a is a modulating condensing boiler from the Trinity series, rated at 46 MBH output with 93 percent AFUE efficiency. Designed for hydronic heating applications, it meets ASME pressure vessel standards and accepts both natural gas and liquid propane fuel inputs. The modulating burner adjusts firing rate to match load demand, reducing short-cycling and improving seasonal efficiency. Licensed plumbers and hydronic heating technicians are the typical installers for this unit. Note that the tx51a was discontinued by NTI in 2021 and is no longer in current production.

The tx51a fits residential and light-commercial hydronic heating systems where high-efficiency, space-saving boiler equipment is required. Its compact Trinity-series cabinet suits retrofit installations in mechanical rooms with limited clearance. The dual-fuel capability makes it suitable for job sites served by either natural gas utility lines or bulk propane tanks, giving installers flexibility across different service territories and fuel availability conditions.

Key Features

• 46 MBH output capacity for residential and light-commercial hydronic loads
• 93 percent AFUE condensing efficiency reduces operating fuel costs
• Modulating burner matches firing rate to real-time heat demand
• ASME-certified pressure vessel construction
• Dual-fuel operation on natural gas or liquid propane
• Trinity series compact cabinet design for space-constrained mechanical rooms

Compatibility

Designed as an OEM-style unit within the NTI Trinity modulating condensing boiler series. Consult current NTI documentation for compatible controls, venting components, and hydronic accessories appropriate to this model.

Installation Notes

Installation must be performed by a licensed plumber or hydronic heating contractor in accordance with local mechanical codes and the manufacturer's installation manual. Shut off gas supply and electrical power to the system before any service or connection work. Condensing boilers require a properly sized condensate drain and approved venting materials rated for acidic flue gas. Because this unit has been discontinued since 2021, verify replacement part availability and current code compliance requirements before installation.

Technical Specifications

• Output Capacity: 46 MBH
• AFUE Efficiency: 93 percent
• Fuel Type: Natural Gas or Liquid Propane
• Pressure Vessel Certification: ASME
• Burner Type: Modulating
• Product Status: Discontinued 2021

Standard Information

• Brand: NTI
• Manufacturer Part Number: tx51a