A self-paced interactive playbook covering all 46 HVAC modules in the McCarthy Services training library, plus a complete Rheem product decoder (McCarthy's preferred brand) and DMV-specific 2026 rebate intel across every major utility. Residential focus, with the math, visuals, and sales angles built in. Click the diagrams. Run the calculators. Skip the boring parts.
Compression. Condensation. Expansion. Evaporation. The four stages that everything else is built on.
Heat pump. Gas furnace. Straight AC. What each one is, how it differs, and when to recommend it.
Superheat. Subcooling. Static pressure. SEER. The numbers that tell you whether the equipment is sick or healthy.
R, C, Y, W, G, O, B. Thermostats. Capacitors. Fan motors. The low-voltage language of every system.
Short cycling. No heat. No cool. Frozen coil. Decision trees that get you from symptom to cause.
Good. Better. Best. Carrier vs Trane vs Rheem. The A2L refrigerant transition. How to position.
2026 federal landscape, EmPOWER Maryland, Dominion + Washington Gas + Pepco. The actual money still on the table after the OBBBA repeal.
Go top to bottom the first pass. The cycle in Tier 1 is non-negotiable. If you can explain the four states of refrigerant out loud to your kids, you have already passed half the test that any HVAC veteran would give you in an interview.
The compressor takes low-pressure, low-temperature refrigerant vapor from the evaporator and squeezes it. Squeezing a gas raises both its pressure and its temperature dramatically. The refrigerant leaves the compressor as a hot, high-pressure vapor ready to dump its heat outside.
Compress, Condense, Expand, Evaporate. The same word order, every time, every system. If a tech ever quizzes you, this is the answer they want to hear in this order, with confidence.
One BTU (British Thermal Unit) is the heat it takes to raise the temperature of one pound of water by one degree Fahrenheit. That's it. About the energy released by lighting one wooden kitchen match.
A BTU is a quantity of energy (like calories). A BTU/hr is a rate of energy (like calories per hour). HVAC equipment is always rated in BTU/hr because we care about how fast it can heat or cool, not the total over time.
When you see a 36,000 BTU system, it really means 36,000 BTU per hour. The "/hr" gets dropped in casual conversation but it's always implied.
Before mechanical AC existed, people cooled buildings by hauling in blocks of ice. Melting one ton of ice over 24 hours absorbs roughly 12,000 BTU/hr of heat.
So when we say "3-ton AC," we mean it can remove heat at the rate of three tons of ice melting per day. 1 ton = 12,000 BTU/hr. Forever. Memorize it.
Drag the slider to see what produces or requires that level of heat. Calibrating your gut to these numbers means you'll never need to look up "how big a system does a 2,000 sq ft home need" again.
A 1,000-watt kitchen microwave outputs 3,412 BTU/hr of heat. Run it for an hour and it produces the same heat as a small AC unit removes in 17 minutes.
Rough rule of thumb for the DMV climate. A real installer should always do a Manual J load calculation, but this lets you sanity-check what a customer says they need.
DMV is humid in summer and chilly in winter. Oversized systems are the #1 mistake in this market. An oversized AC cools the air too fast, shuts off before pulling humidity out, and leaves the house cold but clammy. Customers complain even though the equipment is "bigger." Right-size, don't oversize.
Furnaces are rated by input BTU/hr, not output. An 80,000 BTU/hr furnace burns enough gas to release 80,000 BTU/hr of heat. But not all of that heat makes it into your house.
Why this matters in sales: Two furnaces with identical 80,000 BTU input ratings deliver wildly different heat to the house. Higher AFUE = more heat per dollar of gas burned. Over 15 years, the difference is real money. Customers don't know this. Telling them is your edge.
AFUE is the percentage of fuel energy that actually becomes useful heat inside the house, averaged across an entire heating season. A 90% AFUE furnace burns $100 of gas and delivers $90 of heat to the home. The other $10 went up the flue, leaked from the cabinet, or was lost to cycling inefficiency.
It's an annual average, not a steady-state efficiency. It accounts for startup losses, cycling losses, and standby losses across hundreds of run cycles per winter. That's why it's a lower number than the steady-state combustion efficiency a meter would show during a tune-up.
How completely the burner converts gas into heat at the moment of combustion. Modern furnaces hit 98%+ here, easy. This is rarely the limiting factor.
How much of the combustion heat actually transfers through the metal walls of the exchanger into the airstream. This is where 80% vs 95% gets decided. Single-exchanger furnaces leak hot exhaust up the flue. Condensing furnaces add a SECOND heat exchanger that captures even more.
Every time the furnace fires up, there's a warm-up period where it's burning fuel but not yet delivering full heat. Same on shutdown — the heat exchanger is hot but the blower stops too soon. Two-stage and modulating burners run longer at low fire, dramatically cutting cycling losses.
Old furnaces had a standing pilot light burning gas 24/7. Modern furnaces use electronic ignition (hot surface or intermittent spark). Eliminating the pilot alone saves 1-2% AFUE annually. Every modern furnace does this.
Single heat exchanger. Combustion gases exit through a metal flue (Type B vent) at around 350-400°F. The 20% loss is real heat going up the chimney. Cheapest furnace tier. Federal minimum in most of the South, but Maryland and DC require 90%+ in many new install applications.
Adds a secondary heat exchanger that captures heat from the exhaust gases. So much heat is removed that water vapor in the exhaust condenses into liquid (hence "condensing furnace"). Exhaust temp drops to ~100-130°F, can vent through PVC pipe instead of metal flue. Requires a condensate drain.
Same condensing design plus a modulating burner that can run anywhere from 35% to 100% of capacity. Pairs with a variable-speed ECM blower. Runs LONG, LOW cycles instead of short bursts. Almost no cycling losses. The most comfortable furnace experience because temperature swings disappear.
Walk up to a house. Look at the vent. Metal flue pipe through the roof = 80% AFUE furnace. White PVC pipe through a sidewall = 90%+ condensing furnace. You can pre-qualify a sales call from the curb just by spotting the vent material.
Drag the sliders to see annual gas cost savings when upgrading from an old 80% furnace to a higher-efficiency unit.
Formula: New annual cost = Old cost × (Old AFUE ÷ New AFUE). The savings compound over a 15-20 year furnace lifespan, often paying back the upgrade premium in 6-10 years on top of the comfort gains.
Total cooling output (BTU) divided by total electricity used (Wh) over a typical cooling season. The "MPG of air conditioning." Higher = more efficient.
Cooling output divided by electricity at a SINGLE peak condition (95°F outdoor, 80°F indoor). Tells you how the system performs on the hottest day of the year, not a season average.
Total heat delivered (BTU) divided by total electricity used (Wh) over a typical heating season. ONLY shows up on heat pumps. AC-only units don't have this rating.
Heat output divided by electrical input at a single instant. A COP of 3 means the system delivers 3 units of heat per 1 unit of electricity. Used in engineering specs, not customer-facing labels.
In January 2023, the DOE changed how SEER is tested. The new test method puts the equipment under higher external static pressure — meaning the blower has to fight more duct resistance, just like in a real house. This is a more realistic and slightly harder test.
Same physical equipment, tested two ways, will score lower under the new SEER2 method. A unit that was rated 16 SEER under the old method is roughly 15.2 SEER2 under the new one.
An older system labeled "16 SEER" is roughly equivalent to a new "15.2 SEER2" unit. Same machine, new ruler. The DOE didn't make air conditioners worse, they just made the test honest.
The DOE splits the U.S. into three regions for minimum efficiency standards. The DMV sits in the North region (with an asterisk for some Virginia counties).
Split systems for split-system AC. Heat pumps now required to be 14.3 SEER2 nationwide.
Higher cooling minimums because cooling load is higher. Southwest adds an EER2 floor.
Voluntary upgrade tier. Qualifies for many utility rebates. Premium tier above this.
When the customer asks "how efficient is it?" — this is the headline number. Used for utility rebates, ENERGY STAR qualification, and most marketing.
When you're comparing performance on the hottest days. Two units with the same SEER2 can have very different EER2 — the higher EER2 wins for DMV summer humidity.
Heat pump customers asking "will it heat my house in winter?" Higher HSPF2 = more heat per kWh. A premium 9.0 HSPF2 heat pump costs about half as much to run as a 7.5 HSPF2 unit.
Almost never on the customer's spec sheet. You'll see it in engineering docs and cold-climate heat pump data. Useful when comparing how a heat pump performs at low outdoor temps.
The box outside the house. Houses the compressor, condenser coil, and condenser fan. This is the AC-only version: cooling only, no winter heat. Visually very similar to a heat pump outdoor unit (see next card) but simpler inside.
Looks 90% identical to the AC condenser, but with three giveaways: an accumulator tank on the side (catches liquid refrigerant during defrost), a defrost sensor on the outdoor coil, and a raised snow stand (since the outdoor unit produces condensation in winter that would otherwise freeze around its base).
Lives in the basement, attic, or utility closet. The cabinet holds the burners (top section behind sight glass) and the blower (bottom section). Connects to gas line and flue. The evap coil typically sits on top.
All-electric alternative to a furnace. Houses the evap coil (A-shaped, on top), the blower (bottom), and sometimes electric heat strips. Used with heat pumps in all-electric homes.
All components in one cabinet sitting on the roof or a concrete pad. Compressor, condenser, evap coil, blower, sometimes burners — all together. Common on small commercial buildings and some manufactured homes. Less common in DMV residential.
Ductless system. The indoor "head" mounts on the wall and blows conditioned air directly. Pairs with a small outdoor heat pump unit by a refrigerant line set (no ducts). One outdoor unit can serve multiple zones.
The indoor heat exchanger. Sits on top of the furnace (or inside the air handler). House air gets pulled across the coil. The coil is cold (40°F), the air gives up heat, and condensation drips into the pan and out the drain.
A brand-new $15,000 system installed onto bad ductwork will perform like a $5,000 system. Customers don't know this. When you spot duct issues during a sales visit, calling them out honestly — and recommending a duct contractor referral instead of just selling the box — builds trust that closes future deals. It also protects McCarthy from "the new system doesn't work right" callbacks.
Side view of a residential ducted system. Furnace in the basement, supply ducts going up to each floor, return ducts pulling air back. Hover or look closely at each labeled component.
The box-shaped chamber directly on top of the furnace or air handler. Conditioned air leaves the equipment, fills the plenum, and gets distributed into the trunk and branches from there.
Think of it like a manifold: one inlet, many outlets.
The main duct that runs horizontally from the supply plenum across the basement or attic. The "highway" that branches feed off of. Sized for the full system airflow — usually 18" to 24" wide on residential.
Sometimes reduced step-down sized along its length as branches peel off.
Smaller round or rectangular ducts that tap off the trunk and carry air to individual rooms. Typically 6" to 10" diameter for residential. One branch per supply register, usually.
Can be rigid sheet metal, flex (insulated plastic), or fiberboard.
The vent in the floor, ceiling, or wall of a room where conditioned air enters. The customer-facing end of the supply duct system. Usually has adjustable louvers and a damper behind them.
"Vent" is the casual term; "register" is the trade term.
The (usually larger) vent in a central wall or hallway that pulls air OUT of the house. Most residential systems have one large return per floor, centrally located, not one per room.
If a customer has too few returns, the blower starves and static pressure climbs.
The path that pulls air back from return grilles, through the filter, and into the blower section of the furnace or air handler. Sometimes a discrete sheet-metal duct; in older homes often just a "panned-off" floor joist cavity.
Panned joist returns leak heavily. Sheet metal returns are the gold standard.
Where the return air filter sits, typically just before the blower. Either inside the return plenum (1" filter slot on the side of the furnace cabinet) or remote at the return grille (4-5" media filter).
Customers who say "I never change the filter" are telling you they've damaged their system.
The 90-degree metal transition piece between a branch duct and the register/grille. Goes through the floor or wall. Easy to spot in unfinished basements.
Improperly sealed boots are a major source of duct leakage.
An adjustable internal flap in a branch duct (or at the register) that restricts airflow. Used to balance the system — bedrooms that get too cold can have dampers partially closed.
Customers often close registers thinking they save energy. They don't — they just raise static pressure.
Galvanized steel, rectangular or round. Smooth interior = lowest pressure loss. Lasts 30+ years. Requires skilled installation (sheet metal trade).
Plastic inner liner over a coiled wire spring, wrapped in fiberglass insulation, sleeved in vinyl or foil. Cheap and fast to install. The most common branch duct in 2026 residential.
Rigid fiberglass panels assembled into rectangular duct shapes. Cheap, pre-insulated. Was common in the 1980s-90s. Now considered outdated due to interior fiber shedding into the airstream.
If you spot any of these on a sales call, the equipment alone won't fix the comfort complaint. Note them in your write-up and discuss honestly with the customer.
Flex duct draped over rafters, kinked at sharp angles, or sagging in long unsupported runs. Each kink chokes airflow like a clogged garden hose. Common in attics where installers were rushed.
Visible gaps where sheet metal sections meet, or duct tape (yes the irony) peeling off. Industry standard is mastic sealant + mesh tape on every joint. Average home leaks 20-30% of airflow into wall cavities and unconditioned spaces.
A 2-story house with only one return grille on the first floor. The second floor can't dump air efficiently, so its rooms stay hot/cold. Classic in builder-grade homes built fast and cheap.
Supply ducts running through hot attics or cold crawl spaces with no insulation around them. The conditioned air loses energy to the unconditioned space before it reaches the register. Add insulation or relocate ducts.
Customer has closed off "rooms they don't use." This raises static pressure across the whole system, strains the blower, can crack the heat exchanger, and saves zero energy. Open them all back up.
Return air pulled through the cavity between floor joists with a sheet metal panel nailed to the bottom. Pre-1990s standard practice. These leak heavily and can pull dirty crawl space air or even combustion gases into the return.
You're not the duct contractor. But you can say: "I'm noticing some duct issues that could limit how well your new system performs. We don't do ductwork at McCarthy, but I'd recommend getting a duct inspection from [approved partner] before or right after your install. That'll get you the comfort improvement you're paying for." This honesty wins more deals than it costs.
The single biggest determinant of customer satisfaction is whether the system is sized correctly. An oversized AC cools too fast, doesn't pull humidity out, and short-cycles itself to death. An undersized AC runs constantly and never catches up on the hottest days. Right-sizing beats brand selection every time.
Adjust the 8 inputs below to model a customer's home. The output updates instantly with cooling tons needed, furnace BTU input, and a suggested Rheem tier.
Larger home benefits from Classic Plus two-stage cooling for better humidity control across longer run cycles. Consider variable-speed (RA19AY Prestige) for premium comfort.
For DMV climate, this calc lands close to the rule of thumb (1 ton per 500-600 sq ft). If the existing system is wildly different from this calculation, ask why — the previous installer may have oversized to "be safe," which created the comfort complaints the customer is now trying to fix.
"1 ton per 600 sq ft" gets quoted constantly. It's a starting point, not an answer. Here's the same 2,000 sq ft home, sized three ways:
2,000 ÷ 600. Assumes "average" home. Ignores all real conditions.
The calculator above. Adjusts for the 8 most-impactful variables.
ACCA standard. Room-by-room load calc, ductwork modeling, infiltration tests. Takes hours, done by McCarthy's engineer.
Use the calculator above on every sales call. If the result is more than 0.5 ton different from the existing system, that's a conversation worth having with the customer. If the result is within 0.5 ton, the existing size is fine and you can match it confidently.
Manual J uses the local "1% cooling" and "99% heating" design temperatures — the temperatures the equipment must handle on the hottest and coldest 1% of hours per year. Here's the DMV.
A heat pump's capacity drops as outdoor temp drops. At 47°F outdoor, a 3-ton heat pump puts out 36,000 BTU/hr. At 17°F (DC's 99% design temp), the same heat pump might only deliver 22,000 BTU/hr. That's why every DMV heat pump install needs sized backup heat strips — usually 5kW to 10kW (17,000-34,000 BTU/hr) — to cover the gap on the coldest days.
"You have a 4-ton now, let's put in a 4-ton." The original installer might have oversized. Always run the calc.
Calc says 2.7 tons? Install 2.5 ton with a properly-sized variable-speed system, not 3 ton. Bigger = worse humidity control.
A 4-ton AC needs ducts sized for ~1,600 CFM. Old ducts sized for a 2-ton can't deliver it. The bigger system will under-perform.
Quoting a heat pump install without specifying the kW of backup heat is a recipe for a cold customer in January. Spec the strips.
Customer added a sunroom but didn't extend the duct system. Don't quote a bigger central AC — quote a mini-split for the addition only.
How much hotter the refrigerant vapor is than the temperature it boiled at. Tells you if the evaporator is being fed enough refrigerant.
How much cooler the liquid refrigerant is than the temperature it condensed at. Tells you the charge level on TXV systems.
For fixed-orifice systems (no TXV), you don't get to pick a superheat. You calculate what it should be based on indoor and outdoor conditions.
How much total heat (BTU/hr) the system is moving. Used to verify the equipment is producing the capacity it's rated for.
Static pressure is the resistance the duct system fights against. Too high and the blower is working too hard. This is the #1 hidden cause of HVAC complaints in DMV homes.
Seasonal Energy Efficiency Ratio. Higher = more cooling per kWh. SEER2 is the 2023-onward testing standard, slightly stricter than old SEER.
If a tech walks up to an outdoor unit and the suction line (the fat insulated one) feels cool but not freezing, the system is probably charged correctly. If it's sweating heavily or has frost on it, there's an airflow or charge problem. Static pressure is usually the cause they don't check.
The "live" leg from the transformer. Every thermostat call (Y, W, G, etc.) energizes a relay by connecting R back to that terminal. Without R, nothing works.
Color: Red, always.
The return leg back to the transformer. Older mechanical thermostats didn't need a C wire. Every smart thermostat does, because it needs constant power to run the screen and WiFi.
Color: Black or blue, depending on installer.
When the thermostat closes Y to R, the outdoor contactor pulls in and the compressor starts. This is your cooling demand.
Color: Yellow, almost always.
Closing W to R triggers the furnace control board to start the ignition sequence. On a heat pump, W typically calls the backup electric heat strips, not the compressor reversing.
Color: White.
Energizes the indoor blower motor. When the customer hits "Fan On" instead of "Auto," G is what's running. Cooling and heating also energize G internally on the furnace board, so the blower is always pulling air across the coil.
Color: Green.
Heat pumps only. O energizes the reversing valve in cooling mode. Most US heat pumps are wired this way. The valve "rests" in heating mode and engages when you call for cooling.
Color: Orange.
The opposite of O. Some manufacturers (older Rheem, Ruud) energize the reversing valve in heat mode instead of cool. The thermostat must be configured to match.
Color: Blue (when used for RV).
Used on two-stage compressors and dual-fuel systems. First stage starts on Y. If the thermostat can't meet setpoint after a delay, Y2 closes and the compressor ramps up to full capacity.
Color: Brown or pink.
Bypasses the heat pump compressor entirely and runs the electric heat strips only. Used when the compressor is down or when outdoor temps are too low for the heat pump to be efficient.
Color: Light blue or other.
Stores and releases electrical charge to help the compressor and fan motor start and run smoothly. Marked in microfarads (µF / MFD).
The heart of the cycle. Sealed motor + pump in one can. Most expensive component to replace.
The "switch" that connects high-voltage 240V power to the compressor when the thermostat calls for cool.
The fan on top of the outdoor unit. Pulls air across the condenser coil to release heat.
4-way solenoid valve that reverses refrigerant flow. Lets the same equipment heat in winter and cool in summer.
Time-delayed relay that staggers electric heat strips. Prevents huge current draw from kicking on all at once.
Detects ice forming on the outdoor coil in heat mode and triggers a defrost cycle (briefly running in cooling mode to melt the ice).
U-bend in the condensate line. Holds water to block negative blower pressure from sucking air through the drain and stopping water flow.
Suspect: low refrigerant charge (leak), restricted filter or coil airflow, or a failed indoor blower. Check the filter first. If it's clean, measure superheat and subcooling next.
Check: 240V at the disconnect, breaker not tripped, 24V at the contactor coil. If contactor has no 24V, the thermostat or low-voltage circuit is the problem. If it has 24V but doesn't pull in, contactor is bad.
Almost always a failed run capacitor or hard-start kit. Disconnect power, discharge cap, check microfarads. Replace if reading is outside ±6% of nameplate.
Likely an oversized system, dirty condenser coil causing high-pressure trip, or a frozen evaporator. Check filter, coil cleanliness, and refrigerant charge. Restricted airflow is the most common cause in DMV.
Suspect a dirty flame sensor, restricted filter, oversized furnace, or limit switch tripping due to airflow. Pull the flame sensor and clean it with a fine emery cloth. Free fix that saves a service call.
Almost certainly a thermostat location problem (direct sun, near a register) or a faulty thermostat sensor reading wildly. Verify thermostat location. Replace if behavior persists.
Check: power switch, breaker, door safety switch (very common!), and 24V at the gas valve. If door switch is engaged but no power, the control board fuse is usually blown.
Look at the LED diagnostic on the control board. Count the flashes. 3 flashes = pressure switch, 4 = high limit, 5 = flame roll-out, 6 = igniter, etc. Match the code to the manufacturer's chart.
Classic dirty flame sensor. The sensor's job is to confirm flame is present so the gas valve stays open. If it can't sense flame, the board closes the gas valve as a safety. Clean or replace.
Cause: restricted filter, dirty evap coil, or undersized return. The coil gets too cold, condensation freezes, ice builds, airflow drops further. Death spiral. Turn system off, let it thaw 4 hours, replace filter.
Frozen coil melted into the drain pan and overflowed. Or, the drain pan and P-trap are clogged. Always check both. While system is off, clear the trap with a wet/dry vac on the outdoor termination.
Beyond airflow issue, this often means the system is low on refrigerant. Lower charge = lower pressure = lower boil point = ice. Find the leak before recharging or it's back in 30 days.
The HVAC industry has consolidated into about 5 parent companies. Each owns multiple brands that compete with each other on the showroom floor. Knowing the family tree helps you navigate pricing, parts, and customer questions.
Rheem Manufacturing Company acquired Ruud in 1960. Both brands are now owned by Paloma Industries (Japan). The equipment is built in the same factories, with most components interchangeable. The brands exist to let distributors compete in the same market without undercutting each other on price.
In practice: Rheem and Ruud are positioned identically, sold by different wholesalers, and a customer asking "is Ruud as good as Rheem?" can be answered with a confident yes. Model numbers often overlap; the badge changes, the metal doesn't.
Invented modern air conditioning. The household name. Strong dealer network, premium pricing, deep R&D. Best two-stage and variable-speed lineup at the top tier.
Bryant — same factories, value badge.
"It's hard to stop a Trane." Built like commercial equipment, heavy gauge steel, reputation for outlasting competitors. Premium pricing, proprietary parts, excellent build quality.
American Standard — identical product, less marketing markup.
Highest top-tier efficiency ratings in the residential market (SL280V furnace, SL25XPV heat pump). Proprietary parts can mean longer wait and higher service cost. Dealer-only network.
Armstrong, Ducane, Aire-Flo — budget tiers.
Best mid-tier value in the market. The Endeavor Series (launched 2023) is the current flagship lineup with scroll compressors, EcoNet smart controls, and aggressive 10-year warranties. Same equipment under both badges.
Rheem (1925) acquired Ruud (1897) in 1960. Both became Paloma-owned in 1988.
Budget-friendly with surprising longevity. Industry-leading warranties (10-year parts, lifetime compressor on premium tiers). Amana is the upmarket badge with better build finish.
Daikin (the parent brand itself sells mini-splits), Quietflex.
Commercial pedigree crossing into residential. Strong in light commercial and rooftop packaged units. Residential lineup is solid mid-tier but not the first brand most homeowners name.
Coleman, Luxaire, Champion, Fraser-Johnston, Guardian.
Carrier's value badge. Same factories, similar engineering, lower marketing premium. Often the smart pick for budget-conscious customers who still want Carrier-grade engineering.
Carrier (premium), Payne (budget).
Trane's value badge. Identical engineering, identical reliability. The only meaningful difference from Trane is the nameplate and the marketing budget behind it.
Trane (the premium badge).
Newer entrant focused entirely on inverter-driven heat pumps. Aggressive pricing for variable-speed equipment that traditionally costs much more. Disrupting the premium tier on price.
Limited dealer network. Parts may be slower to source.
World leader in mini-split (ductless) systems. Owns Goodman/Amana for ducted residential in North America. The most efficient cold-climate heat pumps available in 2026.
Ductless additions, mini-splits, premium cold-climate.
Daikin's main rival in ductless. M-Series and Hyper-Heat lineup. Hyper-Heat units can heat down to -13°F outdoor, making them viable as primary heat in much of the country.
Premium ductless, all-electric homes, cold-climate.
Every Rheem residential split-system model follows this pattern. Memorize the four positions and you can read any model on the spot.
"N" models meet the Northern-region DOE minimum efficiency requirement. Required for sale in cold-climate states.
All new Rheem units sold in 2026 should be "Y" series. "Z" models are existing inventory or replacement matches for legacy R-410A systems.
RP19AY = Heat Pump (RP) + 19 SEER2 tier + Endeavor generation (A) + R-454B (Y). Top-tier Rheem heat pump on the new refrigerant. RA13NZ = AC (RA) + 13 SEER2 base tier + Northern compliance (N) + R-410A (Z). Entry-level AC for cold regions on legacy refrigerant.
Every active Rheem residential split-system air conditioner and heat pump model. Tonnage range and refrigerant type for each.
| Model | Type | Tier | SEER2 | EER2 | Tons | Refrig |
|---|---|---|---|---|---|---|
| RA19AY | AC | Prestige | 20.0 | 13.0 | 2-5 | R-454B |
| RA18AZ | AC | Prestige | 20.0 | 13.0 | 2-5 | R-410A |
| RA16AY | AC | Classic Plus | 17.0 | 12.0 | 2-5 | R-454B |
| RA16AZ | AC | Classic Plus | 17.0 | 10.5 | 2-5 | R-410A |
| RA15AZ | AC | Classic Plus | 15.2 | 9.8 | 2-5 | R-410A |
| RA15AY | AC | Classic | 16.0 | 13.0 | 1.5-5 | R-454B |
| RA14AY | AC | Classic | 15.2 | 12.0 | 1.5-5 | R-454B |
| RA14AZ | AC | Classic | 16.0 | 13.0 | 1.5-5 | R-410A |
| RA13NY | AC (North) | Classic | 13.4 | 9.0 | 1.5-5 | R-454B |
| RA13NZ | AC (North) | Classic | 15.2 | 12.0 | 1.5-5 | R-410A |
| WA15AY | AC | Select | 15.2 | 12.0 | 1.5-5 | R-454B |
| WA15AZ | AC | Select | 15.2 | 9.8 | 2-5 | R-410A |
| RP19AY | Heat Pump | Prestige | 19.0 | 12.5 | 2-5 | R-454B |
| RP16AZ | Heat Pump | Classic Plus | 17.0 | 10.4 | 2-5 | R-410A |
| RP15AY | Heat Pump | Classic Plus | 15.2 | 11.5 | 2-5 | R-454B |
| RP14AY | Heat Pump | Classic | 14.3 | 11.0 | 1.5-5 | R-454B |
Most McCarthy quotes will land between Classic and Classic Plus. The Classic gets the customer to code at the lowest price; Classic Plus is the "smart upgrade" with two-stage cooling, better dehumidification, and the same 10-year warranty. The Prestige is a deliberate top-shelf option to anchor every conversation higher. Don't lead with Select unless the customer has flat-out asked for the cheapest option.
R-410A has a Global Warming Potential of 2,088. The EPA's AIM Act phased it down. New systems use R-454B (Carrier, Trane, Rheem, Lennox) or R-32 (Daikin), both with GWP under 700.
ASHRAE safety class. "A" = lower toxicity. "2L" = mildly flammable. It will not explode like propane, but it will burn at a specific concentration. Handling rules are stricter.
Leak detection sensors in indoor equipment. New brazing protocols. Different gauges, recovery machines, and vacuum pumps. Old R-410A tools are not all compatible.
"Your old system uses a refrigerant that's being phased out by the EPA. A new A2L system is what's available today, and it's also significantly more efficient, which is part of why your federal tax credit applies."
The One Big Beautiful Bill Act (OBBBA), signed July 4, 2025, repealed both Section 25C and Section 25D effective for any equipment placed in service after December 31, 2025.
For 2025 installs (paperwork filed in early 2026), customers can still claim 25C. For anything installed in 2026 or later, the federal credit is zero. Don't lead with credits that no longer exist. Lead with state and utility rebates, which in the DMV can still stack to $10,000+ per project.
These are point-of-sale rebates funded by the IRA, administered state-by-state. They were not repealed by OBBBA. They're income-qualified and don't go on the customer's tax return; they come off the invoice at install.
For households below 150% of Area Median Income. Up to $8,000 for a heat pump, $1,750 for heat pump water heater, $4,000 for panel upgrades, $1,600 for insulation/air sealing.
Performance-based rebate tied to modeled energy savings. Up to $8,000 standard, $20,000 income-qualified. Requires energy audit and software-modeled improvement plan.
Virginia hasn't passed an EmPOWER-style statewide energy efficiency mandate. The state's IRA HEAR rollout is still in design phase. The rebates that DO exist are utility-by-utility and significantly smaller than what Maryland offers. Know which utility serves the house before you quote anything.
Service area: most of VA including Northern Virginia (DC suburbs), Richmond, Hampton Roads, Charlottesville. 2026 participation "limited basis."
Service area: Fairfax, Fauquier, Loudoun, Prince William, Stafford, Clarke counties + Manassas Park. 163,000+ customers. NOVEC doesn't directly rebate HVAC equipment — sell the financing.
Service area: Northern VA (Fairfax, Arlington, parts of Loudoun, Prince William).
VNG service territory only — Tidewater, Hampton Roads. NOT Northern VA.
Virginia's HEAR program is in design phase as of May 2026. When launched, expect up to $8,000 for heat pumps, $1,750 for HPWH, $4,000 for panel upgrades for households below 150% AMI. Final guidance not yet determined.
Check energy.virginia.gov for current launch status.
EmPOWER Maryland is funded by a surcharge on every utility bill, then redistributed through the utilities as rebates. Since the program started in 2008, it has saved $14.5 billion on installed measures at a cost of $4.1 billion. The flagship HPwES program offers up to $15,000 for fossil-fuel-to-heat-pump conversions. Maryland customers get more rebate dollars than Virginia or DC homeowners by a wide margin.
For replacing oil, propane, or gas with a heat pump. Covers up to 75% of project cost. Requires $100 home energy audit (BPI-certified) and approved contractor. Or up to $10,000 for non-electrification efficiency upgrades.
Per heat pump, applied as a line item on the invoice at install — no customer paperwork. Administered by ICF. Equipment must meet program SEER2/EER2 thresholds. McCarthy's pricing already factors this in.
Available through BGE, Pepco, Delmarva, SMECO, Potomac Edison. ENERGY STAR certified heat pump water heater. Significant for converting gas/electric resistance water heaters. Stacks with EmPOWER HVAC upgrades.
Territory: Baltimore metro, Anne Arundel, Howard, Harford, Carroll counties. ~1.3M customers.
Territory: Montgomery County, Prince George's County (MD suburbs of DC). Stacks with Electrify MC.
Territory: Western MD — Frederick, Hagerstown, Cumberland. Highest stack potential in the state when combining all programs.
Territory: Eastern Shore MD (and Delaware). Higher propane/fuel oil use means bigger electrification savings.
Territory: Charles, St. Mary's, Calvert, parts of Prince George's counties.
Territory: Montgomery, Prince George's, parts of Charles, Calvert, St. Mary's, Frederick.
Adds on top of all utility rebates for Montgomery County residents. Geographic kicker that significantly improves ROI for Bethesda, Rockville, Silver Spring customers. Stacks with Pepco + HPwES + HEAR.
Maryland was awarded $136.8M for HEAR + HOMES. Not yet accepting applications as of May 2026. When live: up to $8,000 heat pump + $1,750 HPWH + $1,600 air sealing/insulation for households below 80% AMI. Half that for 80-150% AMI.
Unlike Maryland's broad rebates, most DC residential energy programs are gated by income. Customers below 80% Area Median Income get aggressive incentives. Above that, DC offers smaller utility-side programs. Knowing the income threshold is the first qualifier on every DC sales call.
For households at or below 80% AMI. Replaces gas/oil heating with heat pump at no out-of-pocket cost. FY26 funds limited — applications currently waitlisted. Renews October 2026.
Two-track: community solar subscription (no install, just bill credits ~$500/yr) and single-family rooftop solar (no-cost install for qualifying homes). Income-qualified only.
For income-qualified households whose heating system has failed. Emergency replacement (often a heat pump) at no cost. Triage program through DOEE — refer customers there for emergencies.
Free insulation, air sealing, ductwork, and weatherization for income-qualified DC residents. Sell weatherization to McCarthy customers as a referral, not a competing product. Lowers their heat pump sizing needs.
Pepco installs a smart thermostat or AC-cycling switch at no cost. Customer earns bill credits during summer peak events. Free smart thermostat to mention on every DC sale. Stacks with all other programs.
Smaller program than Maryland because DC's policy is electrification-first. Furnace and water heater rebates available, but tighter caps. Refer to wgsmartsavings.com/dc for current numbers.
3-ton heat pump install for a homeowner in Potomac Edison territory switching from oil heat. Project list price: $14,000.
| Project price (3-ton heat pump + air handler) | $14,000 |
| EmPOWER HPwES (75% × project, capped) | − $10,500 |
| Potomac Edison Switch-to-Electric | − $4,000 |
| Federal 25C credit (2026) | $0 |
| Customer net cost | $0 |
In Maryland with Potomac Edison territory and oil/propane backout, the math can hit zero or even negative for the customer. The 25C credit being gone barely matters in Maryland. In Virginia it matters more, because state and utility programs are thinner. Always lead with the local stack, not the federal one.
You've already navigated the AURA(sm) pass-through, ITC mechanics, and net metering for your solar customers. Stacking utility rebates in HVAC is the same conceptual move at smaller dollar figures. Most reps don't know what HEAR stands for. By August, you will outsell veterans on this argument.
The trick: the longer the tick, the simpler the fraction. The longest tick between numbers is 1/2". Next longest are the two 1/4" marks. After that are the four 1/8" marks. The shortest, most numerous marks are 1/16".