1.5 Ton EcoTemp 15.2 SEER2 R454B Heat Pump Wall Mount Apartment/Condo Type System W5H5S18AKAAA, FMA5X1800AL
Pairing the W5H5S18AKAAA heat pump with the ECM-powered FMA5X1800AL fan coil gives a compact 18,000 BTU system an AHRI-certified 15.2 SEER2 rating (AHRI #214423914), about one full SEER2 point higher than the PSC version. This R-454B heat pump is meant for studio and small one-bedroom units where the owner pays the utility bill or wants lower monthly costs. It uses a 5-speed ECM blower that keeps airflow steady and lets installers set airflow precisely, in a wall-hung cabinet that fits standard stud spacing.
Is a 1.5 Ton Heat Pump System the Right Size?
The 1.5 ton size is for units with a heating and cooling load near 18,000 BTU per hour. Usually that is a studio, efficiency or compact one-bedroom where a single closet fan coil serves the whole space. In small units, oversizing is the most common mistake. A unit that is too big cools quickly, shuts off, and leaves moisture behind.
Small apartments still vary a lot. Floor level, exposed walls, window direction and the number of residents all change the load. The AC tonnage calculator gives a quick baseline. Pairing the right size with the ECM blower's adjustable airflow helps the system run efficiently through long cycles.
Ideal for: Studios, efficiency apartments, small one-bedroom condos, ADUs and owner-paid utility rentals where operating cost matters most.
Need more capacity? Step up to the 2 Ton EcoTemp 15.5 SEER2 R454B Heat Pump Wall Mount System W5H5S24AKAAA, FMA5X2400AL for larger units that still need ECM efficiency.
Recommended system sizes are general guidelines only. Actual requirements depend on climate, insulation, unit location within the building, window exposure, occupancy, and installation conditions. Request free sizing assistance, contact Budget Heating, or call 813-885-7999.
What's Included
| Outdoor Heat Pump | W5H5S18AKAAA — 1.5 Ton Single-Stage R-454B Heat Pump |
|---|---|
| Indoor Fan Coil | FMA5X1800AL Wall-Hung Multifamily Fan Coil (ECM Motor) |
| Application | Apartment / Condo Split System Heat Pump, Heating & Cooling |
| Refrigerant | R-454B (Low-GWP A2L) |
| Compressor | Single-Stage Scroll Compressor |
| Efficiency | 15.2 SEER2, AHRI Certified #214423914 |
| Electrical | 208/230V, Single Phase, 60 Hz Heat Pump (10.9 MCA / 15 Amp Max Fuse or Breaker) |
| Fan Coil Electrical | 208/230V, Single Phase, 60 Hz |
The FMA5X1800AL uses the same slim 36-1/2" x 20-1/2" x 15" cabinet as the PSC model. It swaps in a 1/3 HP, 5-tap ECM motor that delivers 650 CFM nominal, and the unit weighs 84 lbs, 4 lbs less than the PSC version. Outdoors, the W5H5S18AKAAA needs only a 15 amp maximum breaker, which makes it practical in older buildings with limited electrical service. It ships with 6.5 lbs of R-454B for a 15 ft. line set. Order the FMA5X1800AL ECM wall-mount fan coil on its own when only the indoor unit needs replacing. Optional 5, 7.5 and 10 kW breakered heat kits are available on this page.
Heat Pump & Fan Coil Features
W5H5S18AKAAA Outdoor Heat Pump
- Low 15 amp maximum fuse or breaker and 10.9 MCA
- Single-stage scroll compressor on low-GWP R-454B
- 1/12 HP direct-drive fan with vertical discharge
- Internal pressure relief valve and thermal overload
- Loss of charge switch and suction line accumulator
- Field-installed filter drier and front-seating valves
- Long line capable up to 250 ft. total equivalent length
- Low ambient cooling to 0°F with accessory kit
- Optional sound blanket lowers the rating from 72 to 70 dBA
- Compatible with programmable or standard thermostats
FMA5X1800AL Wall-Hung Fan Coil
- 1/3 HP, 5-tap constant-torque ECM blower motor
- 650 CFM nominal with Tap 3 factory setting
- ECM airflow at 208V stays about the same as at 230V
- Standard TXV with an all-aluminum coil
- Refrigerant leak detection system for R-454B
- Fits between standard stud spacing; 84 lb shipping weight
- Front return, field-convertible to bottom return
- Cabinet air leakage below 1.4% per ASHRAE 193
- 15.5" x 19.5" x 0.75" field-installed filter
- Factory or field-installed 5, 7.5 or 10 kW heat options
Specifications & Manuals
Product documentation includes W5H5S heat pump data, FMA5X ECM fan coil specifications and blower tables, installation and wiring instructions, a service manual, and warranty information.
Frequently Asked Questions
Is the 1.5 ton ECM system a good choice for a studio or one-bedroom apartment?
Yes, when the unit's load is near 18,000 BTU. The W5H5S18AKAAA / FMA5X1800AL is sized for compact living spaces, and the ECM blower adds efficiency for owners who want lower operating costs without moving up in tonnage.
Why does the FMA5X1800AL raise the efficiency to 15.2 SEER2 over the PSC version?
The ECM motor uses less electricity than a PSC motor to move the same air. With the same W5H5S18AKAAA outdoor unit, that brings the AHRI rating from 14.3 SEER2 with the FMA5L1800AL up to 15.2 SEER2.
How many blower speeds does the FMA5X1800AL have?
The FMA5X1800AL has 5 speed taps. Tap 3 is the factory setting for the 1.5 ton size. Installers can move up or down a tap to match the duct system and the airflow the heat pump needs.
Does running on 208V affect FMA5X1800AL airflow?
Very little. Per the manufacturer, FMA5X airflow at 208V is about the same as at 230V because the multi-tap ECM is a constant-torque motor. That helps in buildings served by 208V three-phase transformers.
Can the FMA5X1800AL be converted to a bottom return?
Yes. The fan coil ships set up for front return and can be field-converted to bottom return by relocating the panel, following the installation instructions. Airflow is the same in either configuration.
How long can the refrigerant lines be on the W5H5S18AKAAA?
The W5H5S18AKAAA allows up to 200 ft. actual line length and 250 ft. total equivalent length. Installs beyond 80 ft. with units on the same level, or with large vertical separation, are long-line applications and need the accessories listed in the spec sheet.
W5H5S Technical SpecificationsW5H5S Installation InstructionsW5H5S Customer BrochureFMA5X Technical SpecificationsFMA5X Installation InstructionsFMA5X Warranty CertificateFMA5X Wiring DiagramFMA5X Service Manual
