RH2TY4821STANNJ – AIR HANDLER (4 TON, R454B, 21″, SEER2)

Rheem Endeavor Line RH2TY multipurpose air handler, 48,000 BTU/H nominal on R-454B with a factory TXV and non-communicating controls. It uses a two-stage constant torque 3/4 hp blower (300-1100 RPM, four speeds) delivering 1400 CFM low and 1600 CFM high. The cabinet is 21″ wide, 50 1/2″ tall and 21 11/16″ deep with a 19 1/2″ supply duct, N-Coil, and 3/8″ liquid / 7/8″ vapor sweat connections. Rheem rates the unit for field-installed auxiliary heater kits up to 25 kW.

Specifications published by the manufacturer. Source: manufacturer documentation.

Specs

• SeriesEndeavor Line RH2TY
• Nominal Capacity48,000 BTU/h
• Nominal Tonnage4 ton
• RefrigerantR-454B
• MeteringTXV
• Stages of AirflowTwo-Stage
• Motor TypeConstant Torque
• Coil SeriesN Coil
• Voltage208-240 V, 1 phase, 60 Hz
• Blower Motor3/4 hp
• Blower Motor RPM300-1100
• Air Flow - Low1400 CFM
• Air Flow - High1600 CFM
• Minimum Circuit Ampacity5 A
• Maximum Overcurrent Protection15 A
• Maximum kW Electric Heating25 kW
• Cabinet Width21 in
• Height50 1/2 in
• Depth21 11/16 in
• Supply Duct19 1/2 in
• Liquid Connection3/8 in sweat
• Vapor Connection7/8 in sweat
• Weight128 lb

What is the difference between an air handler and a furnace?

An air handler is a blower and an indoor coil in a cabinet, with a spot for electric heat strips. No burners, no heat exchanger, no flue, no gas. Every BTU of heat comes from resistance strips or a heat pump outside. If the house has Atmos gas at the meter, a furnace heats cheaper per BTU than strips almost every time. Air handlers earn their keep behind a heat pump, or where there is no gas.

How do I match one to the condenser, and does blower type matter?

Tonnage and refrigerant, same as a coil. The RH2TY is R-454B with a factory TXV and a constant-torque ECM blower, five taps, 300 to 1100 RPM. On real duct that beats a PSC, which turns one speed tap and hands back whatever airflow the static steals - at 0.8 inches water column of total external static you feel it. Constant torque holds up much better, and variable speed targets a CFM number and ramps to hit it.

Does the heat kit come with it?

No, it is a separate part number. RXBH kits run 2.25 kW up to 27.6 kW, and 1 kW makes 3,412 BTU. Single-circuit and multi-circuit kits are not interchangeable, and breakers come built into the kit.

So what size breaker and wire do I need?

Whatever the kit says, not what the bare air handler says. Minimum circuit ampacity runs from about 13 amps with no heat to roughly 151 on a big multi-circuit kit, max overcurrent protection 15 to 160 amps. Pick the kit, read the nameplate chart, then pull wire. For DFW a properly sized heat pump balances near 35 to 40F against a design temp around 22F, so 5 to 10 kW backs up most houses. The 20 kW kits we see going in are mostly somebody buying a January bill they did not need.