Midea M thermal Mono Series Dimension Guide

Engineering Data
M thermal A Series Mono(18~30kW)
R32
Commercial Air Conditioners
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M thermal Mono
201910 1
CONTENTS
CONTENTS
Part 1 General Information............................................................................ 3
Part 2 Engineering Data ............................................................................... 17
Part 3 Installation and Field Settings.......................................................... 35
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M thermal Mono
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Midea M thermal Mono Engineering Data Book
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M thermal Mono
202005 3
Part 1 - General Information
Part 1
General Information
1 M thermal Mono System............................................................................ 4
2 Unit Capacities ........................................................................................... 6
3 Nomenclature ............................................................................................ 6
4 System Design and Unit Selection .............................................................. 7
5 Typical Applications ................................................................................... 9
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1M thermal Mono System
1.1 System Schematic
Figure 1-1.1: System schematic
M thermal Mono is an integrated air-to-water space heating, space cooling and domestic hot water heat pump system.
The outdoor heat pump system extracts heat from the outdoor air and transfers this heat through refrigerant piping to the
plate heat exchanger in the hydronic system. The heated water in the hydronic system circulates to low temperature heat
emitters (floor heating loops or low temperature radiators) to provide space heating, and to the domestic hot water tank
to provide domestic hot water. The 4-way valve in the outdoor unit can reverse the refrigerant cycle so that the hydronic
system can provide chilled water for cooling using fan coil units.
M thermal Mono is an integrated air to water heat pump system which is one-stop solution for space heating, space
cooling and domestic hot water. The outdoor heat pump system extracts heat from the outdoor air and transfers this heat
through refrigerant piping to the plate heat exchanger in the hydronic system. The heated water in the hydronic system
circulates to low temperature heat emitters (floor heating loops or low temperature radiators) to provide space heating,
and to the domestic hot water tank to provide domestic hot water. The 4-way valve in the outdoor unit can reverse the
refrigerant cycle so that the hydronic system can provide chilled water for cooling using fan coil units.
The heating capacity of heat pumps decreases with ambient temperature dropping. M thermal Mono can be equipped
with a backup electric heater to provide additional heating capacity for use during extremely cold weather when the heat
pump capacity is insufficient. The backup electric heater also serves as a backup in case of heat pump malfunction and for
anti-freeze protection of the outside water piping in winter.
M thermal Mono Outdoor Unit
Distributor
Collector
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Part 1 - General Information
1.2 System Configurations
M thermal Mono can be configured to run with the electric heater either enabled or disabled and can also be used in
conjunction with an auxiliary heat source such as a boiler.
The chosen configuration affects the size of heat pump that is required. Three typical configurations are described below.
Refer to Figure 1-1.2.
Configuration 1: Heat pump only
The heat pump covers the required capacity and no extra heating capacity is necessary.
Requires selection of larger capacity heat pump and implies higher initial investment.
Ideal for new construction in projects where energy efficiency is paramount.
Configuration 2: Heat pump and backup electric heater
Heat pump covers the required capacity until the ambient temperature drops below the point at which the heat
pump is able to provide sufficient capacity. When the ambient temperature is below this equilibrium point (as shown
in Figure 1-1.2), the backup electric heater supplies the required additional heating capacity.
Best balance between initial investment and running costs, results in lowest lifecycle cost.
Ideal for new construction.
Configuration 3: Heat pump with auxiliary heat source
Heat pump covers the required capacity until the ambient temperature drops below the point at which the heat
pump is able to provide sufficient capacity. When the ambient temperature is below this equilibrium point (as shown
in Figure 1-1.2), depending on the system settings, either the auxiliary heat source supplies the required additional
heating capacity or the heat pump does not run and the auxiliary heat source covers the required capacity.
Enables selection of lower capacity heat pump.
Ideal for refurbishments and upgrades.
Figure 1-1.2: System configurations
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2Unit Capacities
Table 1-2.1: Unit capacities range and appearances
Capacity
18kW
22kW
26kW
30kW
Model
(MHC-)
V18W/D2RN8
V22W/D2RN8
V26W/D2RN8
V30W/D2RN8
Appearance
3Nomenclature
H
30
M
C
V
W
D2
R
-
N8
/
Refrigerant
N8: R32
Power Supply
R: 3-phase, 380-415V, 50Hz
Compressor and fan motor types
D2: All DC
Unit category
W: Outdoor unit
Capacity index
The capacity in kW
Inverter
Mono
Heat pump
Midea
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Part 1 - General Information
4System Design and Unit Selection
4.1 Selection Procedure
Step 1: Total heat load calculation
Calculate conditioned surface area
Select the heat emitters (type, quantity, water temperature and heat load)
Step 2: System configuration
Decide whether to include AHS and set AHS’s switching temperature
Decide whether backup electric heater is enabled or disabled
Step 3: Selection of outdoor units
Determine required total heat load on outdoor units
Set capacity safety factor
Select power supply
Provisionally select M thermal Mono unit capacity based on nominal
capacity
Correct capacity of the outdoor units for the following items:
Outdoor air temperature / Outdoor humidity / Water outlet temperature1/
Altitude / Anti-freeze fluid
Is corrected M thermal Mono unit capacity ≥Required total heat load on
outdoor units2
Yes
No
M thermal Mono system
selection is complete
Select a larger model or enable
backup electric heater operation
Notes:
1. If the required water temperatures of the heat emitters are not all the same, the M thermal Mono’s outlet water temperature setting should be set at the
highest of the heat emitter required water temperatures. If the water outlet design temperature falls between two temperatures listed in the outdoor
unit's capacity table, calculate the corrected capacity by interpolation.
2. Select Mono units which should satisfy both total heating and cooling load requirements.
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4.2 M thermal Leaving Water Temperature (LWT) Selection
The recommended design LTW ranges for different types of heat emitter are:
For floor heating: 30 to 35⁰C
For fan coil units: 30 to 45⁰C
For low temperature radiators: 40 to 50⁰C
4.3 Optimizing System Design
To get the most comfort with the lowest energy consumption with M thermal, it is important to take account of the
following considerations:
Choose heat emitters that allow the heat pump system to operate at as low a hot water temperature as possible
whilst still providing sufficient heating.
Make sure the correct weather dependency curve is selected to match the installation environment (building
structure, climate) as well as ender user’s demands.
Connecting room thermostats (field supplied) to the hydronic system helps prevent excessive space heating by
stopping the outdoor unit and circulator pump when the room temperature is above the thermostat set point.
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5Typical Applications
5.1 Space Heating
The room thermostat is used as a switch. When there is a heating request from the room thermostat, the Mono unit
operates to achieve the target water temperature set on the user interface. When the room temperature reaches the
thermostat’s set temperature, the unit stops.
Figure 1-5.1: Space heating
Table 1-5.1: Space heating
Legend
1
Outdoor unit
5
Room thermostat (field supplied)
1.1
Manometer
6
Drain valve (field supplied)
1.2
Pressure relief valve
7
Fill valve (field supplied)
1.3
Expansion vessel
8
Balance tank (field supplied)
1.4
Plate heat exchanger
8.1
Air purge valve
1.5
Air purge valve
8.2
Drain valve
1.6
Flow switch
9
Expansion vessel (field supplied)
1.7
P_i: Circulation pump inside the unit
10
P_o: Outside circulation pump (field supplied)
2
Y-shape filter
11
Collector / Distributor (field supplied)
3
Stop valve (field supplied)
FHL 1...n
Floor heating loop (field supplied)
4
Wired controller
Notes:
1. The example is just for application illustration; please confirm the exact installation method according to the installation manual.
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