Nomenclature Guide

This page is your go-to resource for understanding the model numbers and codes used in our products. Whether you’re looking to decode specifications or streamline your ordering process, you’ll find everything you need to navigate our product lineup with ease.

HR Series

RR Series

NOTE:

Not all descriptors may appear for each model. See individual product specification documents for complete model number configuration options.

Glossary

Section	Digit Codes	Description
Brand	A–AE Air	AE Air is the commercial division of First Co. and specializes in Chilled Water units and Water Source Heat Pumps. This brand is available only through authorized resellers.
Cabinet Configuration	RUNV LUNV BFLX BFRX BFXX BLXX BRLX BRXX BTFX BTLX BTRX BTXX LBXX LFBX LFRX LFXX LRBX LRXX LTBX LTFX LTRX LTXX RBXX RFBX RFLX RFXX RLBX RLXX RTBX RTFX RTLX RTXX	Cabinet Configuration refers to the supply openings and riser location. The first digit is the riser’s location into the unit (R – Right, L – Left, B – Rear). The second digit is the type of first supply opening discharge (U – Universal, F – Front, L – Left, R – Right, T – Top, B – Rear). The t hird digit is the type of optional second supply opening discharge (F – Front, L – Left, R – Right, T – Top, B – Rear). The fourth digit is unused at this time and will remain “X”. Universal means all supply openings are knock – outs.
Cabinet Height	0–80” 1–88” 88–88″ Standard 65–65″ 76–76″ 80–80″ XX–Special Selection	Please select the desired cabinet height. Note: adjusted heights will restrict available cabinet configurations.
Coil Configuration	30–3 Row 40–4 Row 31–3 Row/1 Row 32–3Row/2 Row 41–4 Row/1 Row	Multiple rows of tubes increase the coil’s surface area allowing it to transfer more heat to the air passing over the coil.
Coil Connection Side	L – Left Hand R – Right Hand	The hot water supply should be connected to the bottom connection of the coil on one side. Please select which side of the unit you prefer the coil connection.
Coil Selection Options	Coil Handing–Left or Right Connection–Single Side Coil Wrapper–Galvanized Steel Fin Material-Aluminum Pressure Test–350 PSI (2.41 Mpa)	Coil handing describes at which side of the coil the header tubes are located, with airflow flowing from behind to front. A single side connection means combination coils have both headers on the same side. Galvanized steel is used to encase the coil and secure it to the unit. Fin coils are constructed of aluminum. The coils are pressure tested to 350 PSI.
Coil System	A – 2 – Pipe Cooling B – 2 – Pipe Heating C – 2 – Pipe Heat/Cool D – 2 – Pipe Heat/Cool/Aux Heat E – 2 – Pipe Cool/Electric Heat F – 4 – Pipe Heat/Cool	A 2-pipe system has one pipe for hot water supply and one for return, and can provide heating or cooling at any given time depending on the water source. A 4-pipe system has two separate pipes for hot water and two for chilled water allowing for simultaneous heating and cooling in different zones of a building.
Control Voltage	A–24V Control	Amount of voltage that operates the controls system
Discharge Air	7–Front, Back, Top	Select the location on the unit from which you prefer the discharge air be expelled.
Heat Type	KW Heat	A higher kW in HVAC indicates more capacity for heating or cooling, but it must be matched with the specific requirements of the space and considered alongside efficiency ratings to ensure optimal performance and energy consumption.
Installation	F – Furred In E – Exposed Cabinet R – E RV Furred In	A cabinet that has been “furred in” has been built into the wall behind sheet rock. An exposed cabinet can be painted to sit directly and open in the designated space. An ERV Furred In unit has an energy recovery ventilator.
Insulation Thickness	2–½” Insulation 3–¾” Insulation	Please select the desired thickness of insulation.
Model	CX	Model based on motor type
Motor Type	E–ECM (3-SPEED)	Electronically Commutated Motors are a type of variable speed motor with built-in inverters and microprocessors that adjust speed based on demand.
Mount Style Thermostat	1–Unit Mount 2–Wall Mount 3–Unit Tamperproof	The thermostat can be mounted directly to the unit, on a wall, or on the unit with a tamperproof guard.
Riser Chase	0-None	Options available for riser chase
Riser Location	0-None	Options available for riser location
Series	HR RR	Name of product family
Service Switch	0–None A–Service Switch	The service switch is a crucial safety and convenience feature that allows technicians or homeowners to quickly and safely shut off power to the system during maintenance or repairs.
Side Discharge	3–Right & Left Openings	Openings available on either side of unit for discharging air
Thermostat	NC – No Controls A1 – HP Unit Mount A2 – HP Wall Mount A3 – HP ADA Unit Mount B – Programmable HP Unit Mount	The thermostat can be mounted directly to the unit, on a wall, or in a handicapped accessible location on the unit. The thermostat can also be programmable or set at a fixed temperature.
Unit Size	CFM	An air – conditioner’s unit size or nominal capacity is the output level it can handle when functioning in either cooling or heating mode. Cubic feet per minute (CFM) measures how much airflow volume passes through a space in a minute.
Voltage	120 / 1Ph/60Hz 208-230 / 1Ph / 60Hz 265 / 1Ph / 60Hz 277 / 1Ph / 60Hz	Voltage is the electrical pressure that pushes an electric current through a circuit. Higher voltage indicates a more powerful pressure. Most HVAC systems use with 115 (120)V or 230V depending on size and capacity.
OPTIONS
Cabinet OPTION	Drain Pan Filter Frame Filter Option Option 1 Option 2	Galvanized or Stainless Steel 1” Standard Frame 1” MERV 3, 4, or 10 Standard Access or Sound Barrier None or Line of Sight Baffle
Construction	D1–Std Galvanized Steel D2–Stainless Steel	Select the material from which you prefer the unit constructed. Galvanized steel is a cost-effective option with moderate corrosion resistance. Stainless steel offers superior durability and corrosion resistance.
Controls Options	Thermostats Thermostat Location Thermostat Option	None, Fan Switch Only, Non-Prog Manual, Non-Prog Auto, Non-Prog w/LCD, Programmable w/LCD, Programmable w/LargeLCD None, Unit Mount, Remote Mount, ADA Unit Mount None
Electrical Options	00–None 0V–Vacated Premises Switch	A Vacated Premises Switch allows the unit to be set to a specific temperature or run time during prolonged periods of vacancy.