Furnaces

Name: Furnaces
Brand: ACE FORGE HVAC

Gas furnaces for dual-fuel and add-on heat pump configurations, 2–5 ton.

Refrigerant:R-454B

Specifications

Detailed dimensional and performance data for this family is being finalised. Ask us for the current submittal sheet.

Furnaces — key specifications
Parameter	Value
Efficiency	95% AFUE
Capacity	2 / 3 / 4 / 5 ton
Refrigerant	R-454B

Values as published in the 2026 product catalogue. Ask us for the model-level submittal sheet before specifying.

Features

✓Pairs with heat pump outdoor units for dual-fuel and add-on retrofits

Overview

A gas furnace in 2, 3, 4 and 5 ton capacities, built as the heating section of a dual-fuel or add-on heat pump system. The range is listed at 95% AFUE, with R-454B as the refrigerant for the matched system. It is the part of a hybrid installation that carries the load when the heat pump cannot, so the furnace and the outdoor unit are normally specified together rather than bought separately.

In a system the furnace sits in the return-air path with the evaporator coil above it, and changeover between gas heat and the heat pump is handled by the system control — the thermostat has to support dual fuel for the arrangement to work. On a retrofit, the existing flue route, gas service and ductwork decide whether a replacement is a drop-in swap.

Where it is used

Dual-fuel replacement of an existing gas furnace alongside a heat pump
Add-on heat pump retrofit where the furnace stays as back-up heat
New-build forced-air heating in areas with a gas service
OEM and private-label builds needing a 2–5 ton gas heating section

Selection & installation notes

01
Size on the calculated heating load, not on the capacity of the furnace being replaced. The listed capacities are 2, 3, 4 and 5 ton.
02
Gas input, airflow, temperature rise and cabinet dimensions vary by capacity — confirm per model on the submittal sheet.
03
R-454B is the refrigerant listed for this range. The coil and the outdoor unit have to be built for the same refrigerant, and refrigerants must not be mixed within a system.
04
On a retrofit, check the flue and venting route, the gas supply size and the return-air opening before quoting. Where the heat pump is expected to heat below the balance point, confirm the control can lock out stages as the design requires.

Common questions

Is the furnace sold on its own, or only as part of a matched system?

Either. It is designed for dual-fuel and add-on configurations and pairs with our heat pump outdoor units, but the 95% AFUE figure and the capacities describe the furnace; system performance is set by the combination.

What refrigerant does it use?

R-454B is listed for this range. Treat it as a system-level decision: the coil and the outdoor unit have to be built for the same refrigerant, and refrigerants must not be mixed within a system.

Where are the per-model specifications?

Gas input, airflow, temperature rise and cabinet dimensions are still being compiled at family level. Ask for the submittal sheet for the capacity you intend to stock rather than quoting from the family figures.