Published systems

The indoor half of a split: an outside-air damper with an economiser, a return damper, supply fan and a DX coil with open refrigerant ports. In a building it pairs with a condensing-unit block, which feeds its liquid line; on its own it solves at a declared feed. Published as an example; the figures below come from the solver.

One indoor unit for the VRF outdoor unit beside it: a fan and a DX coil with both refrigerant ports open, fed across a refrigerant coupling. Four of these on one outdoor unit is a connection ratio of 100 %, which is where the makers rate them. Published as an example; the figures below are solved from this model.

Drake Chillers' 30 HP packaged air-cooled chiller in its R404A build, as this model runs it: the PAC360D3's evaporator and condenser, sized on its R407C table, with Copeland's own map of the same two ZB114KCE scrolls on R404A in place of the R407C one. At 40 °F leaving water on a 95 °F day it makes 21.2 tons against the published 21.7, on 4 % more compressor power than the sheet's EER leaves for it. At 55 °F, the one leaving temperature both of the sheet's tables print, its capacity over the R407C build's is the sheet's within 3 % and its power 5 to 9 % higher: the model holds a condensing refrigerant at its dew point, which credits R407C with about half of its 4.7 K glide, and so sizes the shared condenser short for R404A, which has almost none. The sheet's 0 to 25 °F rows want glycol, which this model does not carry. Modelled from the maker's published data — not verified by the manufacturer. Published as an example; the figures below are solved from this model.

KeepRite's KEZA009H8, a one-fan air-cooled scroll condensing unit for a walk-in cooler, as this model runs it: the Copeland ZB08KAE its manual names — the catalog's own map — on R448A, an air-cooled condenser on the cabinet's face, its fins louvered for the enhanced tube and fin the manual names, and the 100 W EC fan that draws air through it. The condenser's airflow is the one figure fitted, on the manual's R404A cell nearest AHRI 1250's rating point (25 °F suction on a 95 °F day, 9 780 Btu/h): 823 cfm, air the printed fan could move through that coil. That same condenser holds all 216 cells the manual prints for this unit on R404A, R407A, R448A and R407C within −4.4 to +3.8 % (RMS 1.7 %). At 25 °F suction on a 95 °F day it gives 2.83 kW on R448A, against the 9 840 Btu/h (2.88 kW) printed. Modelled from the maker's published data — not verified by the manufacturer. Published as an example; the figures below are solved from this model.

One dwelling's radiators, fed from a plant across a water coupling. It is a single component and that is the point: a radiator is rated, not modelled — the EN 442 output at 75/65/20 °C and a characteristic exponent, with no geometry. Twelve kilowatts at that rating carries a 2.6 kW flat on 40 °C water, which is the low flow temperature a heat pump wants. That four-to-one multiple is the whole cost of a low-temperature retrofit: the same flat on a 70 °C boiler needs a third of the radiator. Published as an example; the figures below are solved from this model.

A liquid-cooled IT load and nothing but water between it and the outside: an immersion tank whose dielectric fluid is cooled by a coil-and-plate exchanger fed straight from a small evaporative cooling tower — no chiller, no air handler, no refrigerant, the arrangement the tank makers sell for data centres. The tank is a **liquid-cooled load**: 45 kW of servers declared as the load, the exchanger between the fluid and the water rated at a point the way a coaxial condenser is, and the solution reports the dielectric temperature the servers sit in — here 39 °C on a 35 °C / 25.6 °C wet-bulb design day, under the 45 °C limit declared. The tower is BAC's VT0-12-E at its published rating. Published as an example; the figures below are solved from this model.

CTS's T-210 — a T-2 cooling tower, 8 tons (34 kW): rated to cool 23 USGPM of water from 95 to 85 °F at a 78 °F entering wet bulb on 1.7 m³/s of air, the maker's own printed airflow, and drawn at those flows with an induced-draft fan on the leaving air, pulling through the fill. Open fill: the water meets the air directly — Braun's enthalpy-basis tower model. The model derives the machine's NTU from that one rated point, so it reproduces the rated leaving water exactly and predicts nothing else — one point per model is an input, not a validation. Modelled from the manufacturer's published data — not verified by Cooling Tower Systems. Published as an example; the figures below are solved from this model.

A computer-room air handler: a deep chilled-water coil and a draw-through plug fan, no outside air, no heater — a data hall is cooled all year. In the example data centre it breathes two halls' return air and takes 14 °C water from the chiller block; the design point here is at 14 °C too. Published as an example; the figures below are solved from this model, not copied from a datasheet.

Midea's 8 HP V4+ outdoor unit as this model runs it — the first small frame: not the 20 HP machine scaled but a condenser declared from the frame's own cabinet (980 × 1630 × 800 mm, a coil wrapping three sides) and its published 11 500 m³/h, with the catalog inverter scroll at the frame's share of the 20 HP pair. Modulated to the rated 25.2 kW the way the control runs it, it draws Midea's own selection software's power input within −2 to +1 % from 25 to 39 °C outdoor at the 100 % combination ratio, capacity falling past 35 °C as the grid does. Modelled from the maker's published data — not verified by the manufacturer. Published as an example; the figures below are solved from this model.

A compact water-cooled chiller: supply fan, face-and-bypass dampers around an indoor air coil, inverter scroll compressor, pipe-in-pipe condenser on a closed condenser-water loop, and an evaporative cooling tower with its own fan and pump. The bypass trades a little total capacity for a markedly drier supply. Published as an example — the figures below are solved from this model, not copied from a datasheet.

A remote condensing unit on a Copeland ZF49K5E low-temperature scroll (R404A) with an air-cooled condenser and its fan: an open suction and liquid line, the load declared under boundary.refLoads (a unit cooler's, pinned hourly in a building). Published as an example; the figures below are solved from this model.

One office floor's radiators, fed from a plant across a water coupling — the flats' emitter at an office's size, rated the way EN 442 rates one. Thirty kilowatts at the rating carries 15 kW on 54 °C water, the flow temperature a heat pump on a warm source reaches comfortably. Published as an example; the figures below are solved from this model.

A campus chilled-water plant: four Copeland ZHT300 scrolls on R513A (a centrifugal stand-in, declared as such) on a pipe-in-pipe evaporator and condenser, a condenser-water pump and a cooling tower with a rated point. Exports 6.5 °C water block to block. Published as an example; the figures below are solved from this model.

EVAPCO's 110-2I12 — an AT cooling tower, 226 nominal tons (995 kW): rated to cool 681 USGPM of water from 95 to 85 °F at a 78 °F entering wet bulb on 30.5 m³/s of air, the maker's own printed airflow, and drawn at those flows with an induced-draft fan on the leaving air, pulling through the fill. Open fill: the water meets the air directly — Braun's enthalpy-basis tower model. The model derives the machine's NTU from that one certified point, so it reproduces the rated leaving water exactly and predicts nothing else — one point per model is an input, not a validation. Modelled from the manufacturer's published data — not verified by EVAPCO. Published as an example; the figures below are solved from this model.

A closed-loop heat-pump dryer: a DX coil that takes the water out of the drying chamber's own 55 °C air, the condenser in the same stream reheating it, a circulation fan — on a Copeland ZWD81KBC digital scroll (R134a, rated to 85 °C condensing) with its 10–100 % modulation declared. Nothing leaves but condensate. Run humidity-led in a building: steered on the chamber's humidity ceiling alone. Published as an example; the figures below are solved from this model.

Samsung's 20 HP DVM S outdoor unit as this model runs it: two catalog R410A inverter scrolls behind an air-cooled condenser, modulated to the rated 56.0 kW the way the control runs it, holding Samsung's published power input within 6 % from 25 to 39 °C outdoor at the 100 % combination ratio, capacity falling past 35 °C as Samsung publishes it. Modelled from the maker's published data — not verified by the manufacturer. Published as an example; the figures below are solved from this model.

KeepRite's KEZA050H8, a one-fan air-cooled scroll condensing unit for walk-in coolers and small cases, as this model runs it: the Copeland ZB38KCE its manual names — the catalog's own map — on R448A, an air-cooled condenser on the cabinet's face, its fins louvered for the enhanced tube and fin the manual names, and the 400 W fan that draws air through it. The condenser's airflow is the one figure fitted, on the manual's R404A cell nearest AHRI 1250's rating point (25 °F suction on a 95 °F day, 43 400 Btu/h), and it stands for the condenser's conductance, not for air: the 4 280 cfm it comes to takes about twice the air power the printed fan could give through that coil, so the fan could not move it — read at the compressor's own rating basis, the tables ask more of the condenser than this model's coil gives behind that fan. That same condenser holds all 214 cells the manual prints for this unit on R404A, R407A, R448A and R407C within −5.1 to +6.7 % (RMS 2.5 %). At 25 °F suction on a 95 °F day it gives 12.68 kW on R448A, against the 44 100 Btu/h (12.92 kW) printed. Modelled from the maker's published data — not verified by the manufacturer. Published as an example; the figures below are solved from this model.

A heat pump whose source is a data centre's cooling loop: a coaxial evaporator on the 18 °C return water a CRAH sends back, a Danfoss VZH052 inverter scroll from the catalog with the maker's eighteen published speed steps setting its part-load power, and a coaxial condenser lifting a heating loop to 54 °C — the arrangement Seattle's Westin Building Exchange and the offices next to it run. The source is warm all year, so the machine works over a 40 K lift instead of an air-source unit's 50–60 K in winter, and the chiller behind it has that much less to reject. It serves no room; it holds its leaving water for whatever draws on it. Published as an example; the figures below are solved from this model.

American Cooling Tower's ACX-1011-1 — an ACX cooling tower, 102 nominal tons (447 kW): rated to cool 306 USGPM of water from 95 to 85 °F at a 78 °F entering wet bulb on 15.7 m³/s of air, the maker's own printed airflow, and drawn at those flows with an induced-draft fan on the leaving air, pulling through the fill. Open fill: the water meets the air directly — Braun's enthalpy-basis tower model. The model derives the machine's NTU from that one certified point, so it reproduces the rated leaving water exactly and predicts nothing else — one point per model is an input, not a validation. Modelled from the manufacturer's published data — not verified by American Cooling Tower. Published as an example; the figures below are solved from this model.

An operating-suite air handler: 40 % outside air, a chilled-water coil, an electric heater, a steam humidifier on boiler steam steered to the rooms' humidity floor, and a supply fan against HEPA static. Published as an example; the figures below are solved from this model.

A 12 HP-class VRF outdoor unit drawn as the frames of that size are built: a catalog inverter scroll and a catalog fixed-speed scroll on one circuit — a bank, the fixed machine running flat out as base load and the inverter trimming — behind a condenser declared from a 12 HP cabinet (980 × 1630 × 800 mm, 11 500 m³/h). Modulated to 33.5 kW the way the control runs it, it draws a maker's published power input within −9 to +3 % from 25 to 39 °C outdoor, the miss at the cool end, where a real unit runs its fixed scroll harder than the staging rule does. Published as an example; the figures below are solved from this model.

KeepRite's KEZA150H8, the largest unit of its KEZ cooler range — a two-fan air-cooled scroll condensing unit — as this model runs it: the Copeland ZB114K5E its manual names — the catalog's own map — on R448A, an air-cooled condenser on the cabinet's face, its fins louvered for the enhanced tube and fin the manual names, and the two fans (1 560 W) that draw air through it. The condenser's airflow is the one figure fitted, on the manual's R404A cell nearest AHRI 1250's rating point (25 °F suction on a 95 °F day, 135 000 Btu/h), and it stands for the condenser's conductance, not for air: the 16 450 cfm it comes to takes about four times the air power the printed fans could give through that coil, so the fans could not move it — read at the compressor's own rating basis, the tables ask more of the condenser than this model's coil gives behind those fans. That same condenser holds all 214 cells the manual prints for this unit on R404A, R407A, R448A and R407C within −6.9 to +5.7 % (RMS 2.4 %). At 25 °F suction on a 95 °F day it gives 38.22 kW on R448A, against the 135 000 Btu/h (39.56 kW) printed. Modelled from the maker's published data — not verified by the manufacturer. Published as an example; the figures below are solved from this model.

Baltimore Aircoil's CXVT-1005-1426-75 — a CXVT evaporative condenser rejecting 6107 kW at a 40.6 °C condensing temperature and a 25.6 °C entering wet bulb, on 114.9 m³/s of the maker's own printed air, with a 55.9 kW fan. The heat comes from outside the drawing, because that is what this machine is: heat rejection, and the plant that sends it the heat is the customer's. Given exactly the rejection BAC certify, the model solves the condensing temperature the machine settles at — which is the reading, and the only figure here that is ours rather than theirs. The rating condition is an inference and the listing says so: BAC's sheets never define the condition of their Base Heat Rejection.

A heat-pump dehumidifier for a pool hall: an eight-row DX coil that takes the water out of the hall's air, a reclaim condenser on the pool water that puts the heat the pool lost back into it first, the condenser in the air stream reheating with the rest — the hot-gas reheat every pool unit dries with — and a supply fan, on eight inverter scroll modules. Run humidity-led in a building: steered on the hall's humidity ceiling alone, the hall's temperature and outside air another machine's. Published as an example; the figures below are solved from this model.