POLAR BEARWATER SOURCE HEAT PUMPS Build a request
NEXT-GENERATION PLATFORM · PROPOSED CONCEPT

Two transport sections. One sealed thermal core.

Design objective: deliver the heat pump to the home in two transport sections intended to be easier to bring through a home's doorways and stairways than one cabinet, then join them on site without opening the refrigerant circuit. No envelope or clearance has been defined yet, so fit through any particular opening is not demonstrated. The thermal core carries the whole refrigerant circuit, including the air coil, so nothing refrigerant-carrying crosses the joint. The second section carries the blower and the controls. Configure it, separate it, walk through site assembly and download the summary.

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Concept status

A proposed next-generation architecture. It is not an available, listed, rated or tested product, and no prototype exists. Legacy confirmed models remain the only products documented in the catalog. Loads, carry weights, envelope, materials, connection sizes and performance are unverified until physical prototypes and engineering checks exist.

INTERACTIVE CONFIGURATION, SEPARATION AND ASSEMBLY

Build a concept configuration.

Choices follow physical compatibility rules. Views show the assembled unit, the two sections separated for transport, service removal paths and the exploded modules. The result is a design-review summary, not a quotation.

Application
Source exchanger
Optional sections

Site assembly demonstration ·

Use the steps to walk through site assembly for this configuration.

    ASSEMBLED VIEW

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    THE TWO TRANSPORT SECTIONS
    What gets carried in, and what stays sealed.
    Two transport sections are what the installer carries into the home. They are distinct from the internal subassemblies (blower tray, filter rack, control panel, condensate pan) that a technician removes for service after the unit is installed.
    

    T1 · transport section
    Transport section 1: thermal core
    The heavier section. It holds the whole refrigerant circuit, so carry weight is set by the compressor and exchangers. No weight target is stated; it is an engineering deliverable and will not be an equal split with section 2.
    Contains
    • Entire sealed refrigerant circuit: compressor, reversing valve, metering devices, filter-drier, source coaxial exchanger, optional desuperheater coil and the application exchanger (air coil, load-water exchanger, or both on the triple-function core)
    • Stainless condensate pan directly under the air coil (air-configured and triple-function cores)
    • Hydraulic strip with external unions for source water, and for load water on water-configured and triple-function cores
    • Core-side isolation valves at the wet transport joint (water-configured cores)
    • Base frame with isolation mounts, levelling feet and hand-holds
    • Return-air opening with slide-out filter rack (air-configured and triple-function cores). Dedicated coil leaving-air passage to the dry joint, sealed by a bulkhead from the compressor, refrigerant piping and electrical space; coil-header penetrations sealed. Passage fit and leakage require validation.
    Functional modules inside
    • M1
    • M3
    • M5
    Internal subassemblies (service, not transport)
    • Filter rack (slide-out, no refrigerant work)
    • Condensate pan and drain fitting (front access, no refrigerant work)
    • Compressor, reversing valve, metering devices, coils (refrigerant recovery required)
    T2 · transport section
    Transport section 2: air-movement and control section
    The lighter section. It contains no refrigerant. On vertical builds its frame bears on the core's top rails through alignment pins; on horizontal builds it stands on its own frame beside the core.
    Contains
    • ECM blower on a slide-out tray
    • Supply plenum and duct collar
    • Electrical and control compartment with its own door, above the core's condensate pan on vertical builds
    • Protected connector block for blower, sensors, thermostat and compressor power
    • Optional duct heater section flanged to the supply plenum; optional HRV section connected by field ductwork
    Functional modules inside
    • M2
    • M4
    • M6
    Internal subassemblies (service, not transport)
    • Blower tray (slide-out after plug disconnect)
    • Control panel and relays (own door)
    • Duct heater or HRV section (whole-section removal after electrical isolation)
    Water-to-water variant: Transport section 2 (water-configured): hydraulic and control service section
    • Service-side isolation valves, low-point drains and high-point air vents at the wet transport joint
    • Flow meter and thermometer wells
    • External circulator flanges
    • Electrical and control compartment with its own door
    • Own frame; stands beside the core
    

    Joints between the two sections4 joint types
    IDJointApplies toCrossesDoes not crossConcept constructionRequires validation
    J-AIRDry gasketed air jointw2a-v, w2a-h, w2w2aConditioned air only, from the core's coil outlet into the blower sectionRefrigerant, condensate, waterFlanged perimeter frame on both sections with a closed-cell gasket. Vertical builds: compressed by section 2's weight plus latches, located by alignment pins on the core top rails. Horizontal builds: the sections stand on their own frames and are drawn together by latches or bolts at the vertical flangeGasket material, compression, leakage at operating static pressure, latch rating
    J-ELECProtected electrical connectorw2a-v, w2a-h, w2w, w2w2aLine voltage to the compressor and low-voltage sensor and safety circuitsNothing elseKeyed, latching connector blocks recessed behind a cover so they cannot be damaged in transport; disconnect is external to the unitConnector current rating, strain relief, listing
    J-WETWet unions with isolation on both sides, drain and ventw2wSource and load water between the core exchangers and the service section fittingsRefrigerantA union on each of the four water lines with an isolation valve on the core side and on the service side, leaving a short drainable segment between them; low-point drains and high-point air vents on the service section. The core's exchangers stay filled behind their valves; only the trapped segment is drained before separationUnion and valve size, material and pressure rating; drain and vent sizing; procedure for refilling and air removal; freeze protection of the filled core during transport or storage
    J-LOADStructural bearingw2a-v, w2w2aWeight of section 2 into the core rails and baseLoads are not carried by the gasket, ducts or connectorsSection 2 frame rails bear on the core's top rails through alignment pins; each section stands on its own frame when separatedRail stiffness, pin shear, seismic restraint where required
    

    Site assembly sequences, per configuration4 variants
    Water-to-air, vertical7 steps
    1. 1. Bring both sections to the mechanical room. Each section moves on its own frame with hand-holds. The core is the heavier carry and sets the crew size; section 2 follows.
    2. 2. Place and level the core. Set the core on its isolation feet at the final position with service clearance in front and at the hydraulic strip.
    3. 3. Connect water and condensate at the core. Source (and domestic hot water, where fitted) unions outside the cabinet; condensate trap on the pan drain. Circulators sit in the external piping, as in legacy practice.
    4. 4. Lower section 2 onto the alignment pins. The pins locate the frames; the gasket compresses under the section's weight. Latches complete the joint. Loads pass rail to rail, not through the gasket.
    5. 5. Mate the protected electrical connectors. Keyed connector blocks behind the cover join blower, sensors, thermostat and compressor power. The external disconnect stays open until checks are complete.
    6. 6. Connect ducts. Return duct to the core's filter rack opening; supply duct to section 2's collar, and to the duct heater or HRV ductwork where fitted.
    7. 7. Fill, purge, check and start. Water side filled and purged of air; joint inspected for air leakage; safeties proven; then the compressor is started and flow and temperatures are read at the supplied meter and thermometers.
    Water-to-air, horizontal7 steps
    1. 1. Bring both sections to the space. Each section moves on its own frame with hand-holds. Horizontal sections are never stacked; both stand on their own supports.
    2. 2. Place, support and level the core. Set the core on its isolation feet or hanger rails at the final position, with the return opening and hydraulic strip accessible.
    3. 3. Connect water and condensate at the core. Source (and domestic hot water, where fitted) unions outside the cabinet; condensate trap on the pan drain with the overflow switch required on horizontal builds.
    4. 4. Bring section 2 end to end and draw the flange together. Section 2 stands on its own frame or hangers, is aligned to the core's vertical flange by guide pins, and is drawn onto the gasket with latches or bolts. Neither section carries the other's weight.
    5. 5. Mate the protected electrical connectors. Keyed connector blocks behind the cover join blower, sensors, thermostat and compressor power. The external disconnect stays open until checks are complete.
    6. 6. Connect ducts. Return duct to the core's end filter opening; supply duct to section 2's end collar, and to the duct heater where fitted.
    7. 7. Fill, purge, check and start. Water side filled and purged of air; joint inspected for air leakage; safeties proven; then the compressor is started and readings taken.
    Water-to-water7 steps
    1. 1. Bring both sections to the mechanical room. The water-configured core and the hydraulic and control service section each move on their own frame with hand-holds.
    2. 2. Place and level the core. Set the core on its isolation feet with the wet-joint unions facing the service section position.
    3. 3. Place the service section beside the core. Each service section stands beside its own core on a separate frame. Align the unions. The optional stacking frame supports two complete units; its structure and installation sequence require validation.
    4. 4. Make up the wet unions with both isolation valves closed. Four unions (source in and out, load in and out). Core-side and service-side valves stay closed so the trapped segment is dry until filling.
    5. 5. Connect external piping and the connectors. Loop and load piping to the service section's circulator flanges; keyed connector blocks join controls to the compressor and sensors. Disconnect stays open.
    6. 6. Fill, vent and purge. Open the service-side valves, fill slowly, open high-point vents until they run clear, then open the core-side valves and verify flow at the meter.
    7. 7. Check and start. Safeties proven; compressor started; entering and leaving temperatures and flow compared with the design.
    Water-to-water-to-air (triple function)7 steps
    1. 1. Bring both sections to the mechanical room. The triple-function core is the heaviest core in the family because it carries two water exchangers and the air coil; section 2 is the air-only section.
    2. 2. Place and level the core. Set the core on its isolation feet with service clearance in front and at the hydraulic strip.
    3. 3. Connect source, load, condensate and domestic hot water at the core. All water circuits end at external unions on the core's strip; the condensate trap goes on the pan drain. No water crosses the transport joint.
    4. 4. Lower the air section onto the alignment pins. Pins locate the frames; the gasket compresses under the section's weight; latches complete the joint.
    5. 5. Mate the protected electrical connectors. Keyed connector blocks join blower, sensors, thermostat and compressor power. Disconnect stays open.
    6. 6. Connect ducts. Return duct to the core's filter rack opening; supply duct to the air section's collar, and to the duct heater where fitted.
    7. 7. Fill, purge, check and start. Both water circuits filled and purged; joint inspected; safeties proven; compressor started and readings taken.
    Water-to-water separation procedure
    1. Isolate power at the external disconnect
    2. Close the isolation valves on both sides of each wet union (core side and service side)
    3. Open the separate T2 service-side drain and vent on each of the four trapped union segments and collect the water; core nipples must pitch toward those drains without pockets. The core exchangers and external piping stay filled behind their valves; drain-down completeness requires validation
    4. Break the unions and move the service section away on its own frame
    5. On reassembly: make up the unions, open the high-point vents, open the service-side valves and fill slowly, purge air until the vents run clear, open the core-side valves, then verify flow at the meter
    

    Arrangement decision: why the core sits on the floor and the air coil stays in it3 options evaluated
    Chosen baseline
    Option A: Core on the floor, air section on top (draw-through)
    The heavy core stays at floor level. Return air enters the core through the filter rack, crosses the air coil, then passes the dry air joint into the blower section, which discharges to the supply duct. The filter is upstream of the coil, the condensate pan stays with the coil, and the controls sit above the pan.
    Why: No refrigerant line crosses the transport joint; the heavier section is never lifted onto another section; condensate never crosses the joint.
    Not chosen
    Option B: Blower section below, core on top (blow-through)
    Return air enters the lower blower section and is pushed up through the coil in the core above.
    Why: The heavier core would have to be lifted onto the blower section during installation, and the condensate pan would sit above the blower and controls, against the legacy practice of keeping controls above the pan.
    Rejected for this concept
    Option C: Coil-only upper section with the compressor below
    The air coil rides in the upper section and the compressor and water exchanger stay below.
    Why: A refrigerant line would cross the transport joint, so separation would need a field refrigerant coupling or recovery. That cannot be shown as a dry joint and contradicts the sealed-circuit objective.
    

    COMPATIBILITY RULES
    Physical rules the configurator enforces.
    Each rule states why it exists.
    • R1. The thermal core is built for one application at the factory (air, water, or triple function) and is not field-convertible; the air section and the hydraulic service section do not interchange on the same core. The application heat exchanger is inside the sealed refrigerant circuit.
    • R2. No refrigerant line crosses the transport joint; only air, water (water-to-water builds) and protected electrical connections do. Separation must not require refrigerant recovery or a field refrigerant coupling.
    • R3. Duct heater and HRV sections require an air-configured or triple-function core with the air-movement section. Both act on the supply, return or ventilation airstream.
    • R4. The HRV section is limited to vertical water-to-air builds. It follows the legacy vertical condo family; horizontal duct geometry is undefined.
    • R5. Stacking applies to water-to-water builds only, as two complete units. No air path crosses the stack, and each unit keeps its own protected circuit.
    • R6. Triple function uses the dedicated M1-T core with proposed taller vertical packaging, pending layout validation of section heights. Two load exchangers plus the air coil are a different sealed core, not a bolt-on to the air-configured core.
    • R7. The desuperheater option adds domestic hot water ports and protective devices; it is not fitted where no domestic circuit exists. Avoids a water dead-leg and unrelieved trapped volume.
    • R8. Every pressurized field joint is outside the cabinet at a union or flange; grommets are penetrations only. Keeps leaks outside the electrical zone and lets the unit be disconnected without cutting pipe.
    

    MODULE REGISTER · CONCEPT BOM
    Six functional module groups inside the two sections.
    Common modules are shared by every build; the service equipment and optional sections give each unit its function. No ratings are stated.
    M1 · common · in T1
    Sealed refrigeration circuit
    The whole refrigerant circuit, factory brazed, charged and sealed inside the thermal core. It includes the application exchanger (air coil, load-water exchanger, or both on the triple-function core), so it is built for one application and is not field-convertible. It has no field refrigerant joints and no refrigerant line crosses the transport joint.
    Variants
    • M1-A air-configured core. Application exchanger is a finned air coil inside the core, with the condensate pan beneath it.
    • M1-W water-configured core. Application exchanger is a second coaxial water heat exchanger; both water circuits end at unions on the core.
    • M1-T triple-function core. A dedicated sealed core with an air coil, a load-water exchanger and its own load and source unions on the strip. It pairs with the air-only section 2 across the dry air joint. The refrigerant circuit arrangement for two load exchangers is undefined and is the largest open engineering item in the concept.
    Contents (concept BOM)
    • Scroll or rotary compressor on isolation mounts
    • Reversing valve
    • Bi-directional metering arrangement for each heat exchanger with the filter-drier in the common liquid line (arrangement to be validated)
    • Coaxial source-water heat exchanger, copper or copper-nickel
    • Optional desuperheater coil (double-wall)
    • Application heat exchanger per variant
    • High- and low-pressure switches
    Service boundary
    Sealed. Any work on this circuit is refrigerant service requiring recovery, evacuation and recharge by a licensed technician. It is reachable from the core's front and side panels; it is never separated at the transport joint.
    Legacy basis Source-supported
    • The water coil can be ordered in copper for most closed loops or copper-nickel for open loops.
    • A desuperheater is a small water coil that takes heat from the compressor discharge through a double-wall heat exchanger to preheat domestic hot water; S6 and S12 in legacy model names denote twin desuperheaters.
    • The reversing valve directs refrigerant to either the air coil or the water coil to switch between heating and cooling; the TX valve regulates refrigerant flow.
    Requires validation Proposed improvement
    • Factory-charged sealed circuit with no field joints
    • Metering arrangement for reversing operation
    • Refrigerant class, charge and compartment sealing (ASHRAE 15 and UL 60335-2-40 to be assessed)
    • Oil return and trap geometry for horizontal builds
    • Triple-function circuit design
    M2 · application · in T2 (filter rack and condensate pan stay on T1)
    Air-movement or hydraulic service equipment
    The non-refrigerant equipment that gives the unit its application. On air and triple-function builds the blower and supply collar live in section 2 across the dry air joint; the filter rack and condensate pan stay on the core because they belong with the coil. On water-to-water builds the valves, drains, vents, meters and circulator flanges form the hydraulic service section.
    Variants
    • M2-A air-movement equipment. ECM blower on a slide-out tray and supply plenum in section 2; slide-out filter rack at the core's return opening; stainless condensate pan under the coil in the core.
    • M2-W hydraulic service equipment. Service-side isolation valves, drains, air vents, flow meter, thermometer wells and external circulator flanges in the service section, joined to the core at the wet unions.
    Contents (concept BOM)
    • ECM blower and motor (air)
    • Supply plenum and collar (air)
    • Filter rack at the core return opening (air)
    • Stainless condensate pan with drain, in the core (air)
    • Isolation valves, drains and air vents (water)
    • Flow meter and thermometer wells (water)
    Service boundary
    Blower tray, filters, condensate pan and hydraulic fittings are removable without refrigerant work. Air-coil work is refrigerant service on the core.
    Legacy basis Source-supported
    • The condensate pan is stainless steel.
    • Closed-loop circulators are installed in the piping just outside the heat pump; hot-water circulators use bronze housings for the domestic circuit.
    • A flow meter and entering and leaving water thermometers are supplied so system performance can be checked on site.
    Requires validation Proposed improvement
    • Blower slide-out clearance and weight
    • Condensate pan slope and overflow protection for horizontal builds
    • Air-side static pressure with filters and optional sections
    • Drain, vent and refill procedure for the wet joint
    M3 · common · in T1
    Hydraulic strip
    A fixed connection strip on the core carrying every water and condensate penetration through grommets. Pressurized field joints are unions or flanges outside the cabinet, never at the grommet. On water-to-water builds the unions, with isolation valves on both sides, are the wet transport joint to the service section.
    Contents (concept BOM)
    • Source water in and out
    • Load water in and out (water-configured and triple-function cores)
    • Domestic hot water in and out (desuperheater option)
    • Condensate drain (air-configured and triple-function cores)
    • Core-side isolation valves (water-configured cores)
    • Pipe grommets at each penetration
    Service boundary
    External unions allow the core to be isolated and disconnected without cutting pipe. Circulators sit in the external piping, following legacy practice.
    Legacy basis Source-supported
    • Cabinets are satin-coat galvanized steel with baked powder coat; all water pipe openings have rubber grommets; cabinets carry 1-inch acoustic lining.
    • Closed-loop circulators are installed in the piping just outside the heat pump; hot-water circulators use bronze housings for the domestic circuit.
    Requires validation Proposed improvement
    • Connection sizes, materials and pressure ratings
    • One strip layout serving air, water, horizontal and triple-function cores
    • Relief valve, high limit and flow proving on the desuperheater circuit
    M4 · common · in T2
    Electrical and control compartment
    A separate compartment with its own door in section 2. On vertical builds it sits above the core's condensate pan and drains, which reduces its exposure to condensate leaks; pan overflow protection and compartment isolation remain design considerations. It is separated from the refrigerant space by the transport joint. Standard relays and a generic anti-short-cycle board follow the legacy philosophy. Power to the compressor crosses the joint through the protected connector.
    Contents (concept BOM)
    • Compressor contactor and relays
    • Low-voltage transformer
    • Anti-short-cycle and lock-out board (generic, off the shelf)
    • Terminal strip for thermostat and accessories
    • Required protective devices: high- and low-pressure cutouts, source flow or freeze protection, condensate overflow switch on horizontal builds, duct heater airflow proving and limits interlocked with the blower
    Service boundary
    Own door. Line-voltage disconnect is external to the unit.
    Legacy basis Source-supported
    • Electrical control cabinetry is located above the condensate pan and drains.
    • Standard relays are used instead of proprietary circuit boards; one generic anti-short-cycle and lock-out board is used and can be sourced from any refrigeration wholesaler.
    Requires validation Proposed improvement
    • Protective device schedule and listing
    • Separation between electrical compartment and refrigerant space
    • Connector rating across the transport joint
    • Wiring diagram in the legacy full-colour style
    M5 · common · in T1 and T2 (each section has its own frame)
    Frames and enclosure
    Each transport section has its own frame so it stands and travels on its own. The core frame carries isolation mounts and levelling feet. On vertical builds section 2's frame bears on the core's top rails through alignment pins; on horizontal and water-to-water builds section 2 stands on its own supports beside the core. Powder-coated galvanized panels, 1-inch acoustic lining and removable front and side panels follow legacy construction.
    Variants
    • Vertical: section 2 on top of the core. Dry air joint is horizontal at the top of the core.
    • Proposed taller vertical packaging: air section above a triple-function core. Same joint as vertical; load and source unions on the core's strip. Section heights are undefined; the taller packaging is proposed pending layout validation.
    • Horizontal: sections end to end. Dry air joint is vertical between the core and the blower section; each section on its own supports; end discharge assumed.
    • Low water-to-water: service section beside the core. Wet unions between the sections; each on its own frame; stackable as two complete units on a frame requiring structural rating.
    Contents (concept BOM)
    • Core base frame with isolation mounts, levelling feet and hand-holds
    • Section 2 frame with alignment sockets and hand-holds
    • Galvanized, powder-coated panels
    • 1-inch acoustic lining
    • Removable front and side panels
    • Joint flanges and latches
    Service boundary
    Panels are removable without tools on the concept; fastener type is undefined.
    Legacy basis Source-supported
    • Cabinets are satin-coat galvanized steel with baked powder coat; all water pipe openings have rubber grommets; cabinets carry 1-inch acoustic lining.
    Requires validation Proposed improvement
    • Acoustic lining flame spread, erosion and acoustic performance
    • Panel stiffness and vibration
    • Structural load path through the joint, and for stacking and seismic restraint
    • Envelope, doorway and stairway clearance targets and carry weight per section
    M6 · optional · in T2, field ductwork, or a separate frame for stacking
    Optional sections
    Field-attachable sections that contain no refrigerant joints. Each one must satisfy the compatibility rules and adds its own protective devices and electrical coordination.
    Variants
    • Desuperheater domestic hot water tie-in. A factory option inside the core plus domestic hot water ports on the strip. Ordered only when a domestic hot water circuit exists.
    • Electric duct heater section. Supply-side add-on flanged to section 2's plenum, with airflow proving and redundant limits interlocked with the blower.
    • Heat recovery ventilator section. A separate section connected by field ductwork on both sides: fresh air is delivered into the core's return path upstream of the filter, and stale air is drawn from the return or supply path as the balancing design requires; outdoor air and exhaust collars are on the HRV. It follows the legacy condo family with a built-in HRV but is not shown as a supply-only attachment.
    • Stacking frame for a second complete unit. Two complete, independently protected water-to-water units on a frame requiring structural rating. It is not capacity doubling of one circuit.
    Contents (concept BOM)
    • Duct heater section
    • HRV section with field ductwork to return and supply
    • Stacking frame
    • Domestic hot water ports
    Service boundary
    Each section is removable as a whole after electrical isolation.
    Legacy basis Source-supported
    • A desuperheater is a small water coil that takes heat from the compressor discharge through a double-wall heat exchanger to preheat domestic hot water; S6 and S12 in legacy model names denote twin desuperheaters.
    • K5, K10, K15 and K20 in legacy model names denote electric duct heaters of 5, 10, 15 and 20 kW.
    • Legacy families include vertical water-to-air, horizontal split water-to-air with a separate air handler, water-to-water, water-to-water-to-air and a condo unit with a built-in heat recovery ventilator.
    Requires validation Proposed improvement
    • Structural load path, seismic restraint and electrical coordination for stacked units
    • Added static pressure against ECM blower capability
    • Combined refrigerant charge in one room for stacked units
    • HRV balancing, defrost and duct routing
    

    INTERFACE MATRIX
    Every connection between sections and modules.
    What crosses each boundary, whether it is made in the factory or the field, whether it is sealed, and what engineering must still validate.
    IDBetweenMediumConcept interfaceFactory or fieldSealedRequires validation
    I1T2 to T1 (J-AIR)Conditioned airFlanged perimeter frames with a closed-cell gasket; alignment pins (vertical) or guide pins and latches (horizontal)Field, dryAir gasketGasket compression and leakage at operating static, latch rating
    I2T2 to T1 (J-ELEC)Line and low voltageKeyed, latching connector blocks recessed behind a coverField, plugn/aConnector current rating, strain relief, listing
    I3T2 to T1 (J-LOAD, vertical builds)StructuralSection 2 rails bear on core rails through pins; each section has its own frameFieldn/aRail stiffness, pin shear, seismic restraint
    I4T2-W to T1-W (J-WET)Source and load waterUnions with isolation valves on the core side and the service side; each of four trapped segments has its own drain and vent on the T2 side of the union. Core nipples pitch toward the service drains; complete drain-down requires validationField, wet (trapped segment drained before separation)Open water circuitUnion and valve size, material, pressure rating; refill and air-removal procedure; freeze protection of the filled core
    I5M1 to M2-A (inside T1)Refrigerant (air coil)Air coil is part of the sealed core; the condensate pan sits under itFactory brazedSealedCoil access for recovery-based service, condensate carry-over
    I6M1 to M3Source waterType L copper stubs through grommets to external unionsField joint outside cabinetOpen water circuitConnection size, material, pressure rating, freeze protection
    I7M1 to M3Domestic hot water (option)Double-wall desuperheater stubs to bronze external fittingsField joint outside cabinetOpen water circuitRelief valve, high limit, flow proving, scald protection
    I8Condensate pan to M3CondensateStainless pan drain through a grommet to an external trap; pan and coil both in T1FieldGravity drainPan slope, trap depth, overflow switch on horizontal builds
    I9M4 to M1 (through J-ELEC)Line and low voltageContactor to compressor and pressure switches to control circuit through the joint connectorField, plugBulkhead on the core sideCompartment separation from refrigerant space
    I10M4 to fieldLine and low voltageExternal disconnect; thermostat and accessory terminal stripFieldn/aDisconnect rating, terminal labelling
    I11M6 heater to T2 and M4Air and electricalSupply-side flanged section with proving switch and limits wired to M4Fieldn/aAirflow proving, limit redundancy, added static pressure
    I12M6 HRV to T1 return path and T2 supply pathAirSeparate HRV section joined by field ductwork: fresh-air duct into the core's return-air path upstream of the filter rack, stale-air duct from the return or supply path per the balancing design, outdoor and exhaust collars on the HRVField ductworkn/aBalancing, defrost, condensate handling in the HRV core, duct routing
    I13M6 stacking frame to M5StructuralFrame requiring structural rating, carrying a second complete two-section unitFieldn/aLoad path, seismic restraint, service clearance to the upper unit
    

    Service removal paths
    • Air filtersSlide-out rack at the core return opening, no tools
      No refrigerant work
    • Blower traySection 2 front, slide-out after panel removal and plug disconnect
      No refrigerant work
    • Controls and relaysOwn door on section 2, no other compartment opened
      No refrigerant work
    • Condensate panCore front panel, below the coil
      No refrigerant work
    • External circulators and unionsOutside the cabinet
      No refrigerant work
    • Hydraulic service section (water-to-water)Isolate both sides, drain the trapped segments, break unions, move the section away
      No refrigerant work
    • Air coilCore front and side panels; refrigerant recovery required
      Refrigerant recovery
    • Compressor, reversing valve, metering devicesCore front and side panels; refrigerant recovery required
      Refrigerant recovery
    

    LEGACY BASIS AND INSPIRATION
    Statements from the supplied documents.
    Every legacy claim the concept leans on, with its source location, and the architectural principles borrowed from the Seresco references.
    IDStatementSource
    L1Electrical control cabinetry is located above the condensate pan and drains.Dennis Campbell, design philosophy document, Cabinet section
    L2Cabinets are satin-coat galvanized steel with baked powder coat; all water pipe openings have rubber grommets; cabinets carry 1-inch acoustic lining.Dennis Campbell, design philosophy document, Cabinet section
    L3The condensate pan is stainless steel.Dennis Campbell, design philosophy document, Cabinet section
    L4Standard relays are used instead of proprietary circuit boards; one generic anti-short-cycle and lock-out board is used and can be sourced from any refrigeration wholesaler.Dennis Campbell, design philosophy document, Electrical Control Components
    L5Closed-loop circulators are installed in the piping just outside the heat pump; hot-water circulators use bronze housings for the domestic circuit.Dennis Campbell, design philosophy document, Circulator Pumps and Hot Water Circulator sections
    L6The water coil can be ordered in copper for most closed loops or copper-nickel for open loops.Dennis Campbell, design philosophy document, Water Coil section
    L7A desuperheater is a small water coil that takes heat from the compressor discharge through a double-wall heat exchanger to preheat domestic hot water; S6 and S12 in legacy model names denote twin desuperheaters.Dennis Campbell, design philosophy document and 16-page specification, page 1
    L8K5, K10, K15 and K20 in legacy model names denote electric duct heaters of 5, 10, 15 and 20 kW.Dennis Campbell, 16-page specification, pages 1 to 3
    L9Legacy families include vertical water-to-air, horizontal split water-to-air with a separate air handler, water-to-water, water-to-water-to-air and a condo unit with a built-in heat recovery ventilator.Dennis Campbell, 16-page specification, pages 1 to 13
    L10A flow meter and entering and leaving water thermometers are supplied so system performance can be checked on site.Dennis Campbell, design philosophy document, Flow Meter and Temperature Thermometers
    L11The reversing valve directs refrigerant to either the air coil or the water coil to switch between heating and cooling; the TX valve regulates refrigerant flow.Dennis Campbell, design philosophy document, Reversing Valve and TX Valve sections
    

    Architectural inspiration
    Principles borrowed, nothing copied
    • Seresco NE Compact Series (product page) ↗
      • Service vestibule kept outside the process airstream so critical components can be serviced while the unit runs
      • Multiple supply-air connection options and mirror configurations for duct flexibility
      • Compact retrofit access and stacked (double-decker) versions to add capacity without extra floor space
    • Seresco NE Series brochure with optional R3 expansion module (PDF) ↗
      • A section that mounts beneath the main unit and can ship separately
      • Field-assembled sections for retrofit, with the mechanical vestibule protecting refrigeration controls
    Architectural principles only. No Seresco geometry, branding, dimensions, weights, performance data or patented mechanisms are used, and a pool dehumidifier is not a water source heat pump.
    Proposed
    What the platform would change
    • Two transport sections instead of one cabinet, joined on site without opening the refrigerant circuit.
    • A factory-sealed thermal core with no field refrigerant joints, built air- or water-configured.
    • Blower, filters, condensate pan, hydraulic fittings and controls removable without refrigerant work.
    • Optional sections (duct heater, HRV, stacking frame, domestic hot water) that follow physical compatibility rules.
    

    Engineering and buildRefrigeration principles, fluid paths, cabinet layers and service order for the legacy design.Drilling-site sequenceHow a closed loop is installed and connected to the core's hydraulic strip.Documented legacy modelsThe 52 source-backed products that exist today.
    

    REFERENCES
    Sources
    Inspiration references and the manufacturer documents the concept is grounded in.
    1. Seresco NE Compact Series (product page) ↗Seresco Technologies. Architectural inspiration only.
    2. Seresco NE Series brochure with optional R3 expansion module (PDF) ↗Seresco Technologies. Architectural inspiration only.
    3. Philosophy for Polar Bear Web Site (historical design philosophy)Dennis Campbell. Cabinet, coil, blower, condensate, circulator and control statements about legacy equipment.
    4. Heat Pumps Manufactured by Polar Bear Water Source Heat Pump Mfg. Inc. (16 pages)Dennis Campbell. Legacy families, cabinet sizes and nomenclature for desuperheaters and duct heaters.