Mitsubishi Electric EHWT17D-MHEDW User manual

INSTALLATION MANUAL
For safe and correct use, read this manual before installing the heat pump unit, which is installed indoors.
FOR INSTALLER
English
Water to Water Heat Pump
EHWT17D-MHEDW
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Accessories (Included)
Adjustable feet Immersion heater
boss tool SD memory card Copper liner for
DHW pipe Gasket O-ring Joint for install
PICV into Module
4 1 1 4 4 4* 1
*For 3-Way valve: O-ring Inner diameter 15.8 mm
For Heating return: O-ring Inner diameter 25.7 mm
For installing PICV into Module: O-ring Inner diameter
21.8 mm and 25.7 mm
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Contents
1. Safety Notices........................................................... 2
2. Introduction............................................................... 8
3. Technical Information .............................................. 8
4. Installation............................................................... 15
4.1 Location .............................................................. 15
4.2 Water/Ambient Loop Quality
and System Preparation .................................... 18
4.3 Water Pipe Work ................................................. 19
4.4 Ambient Loop Pipe Work .................................. 21
4.5 Safety Device Discharge Arrangements (G3) ... 23
4.6 Electrical Connection......................................... 24
5. System Set Up ........................................................ 26
5.1 FTC ...................................................................... 26
5.2 C.B. ...................................................................... 45
6. Commissioning....................................................... 46
7. Service and Maintenance....................................... 47
8. Supplementary information................................... 55
Abbreviations and glossary
No. Abbreviations/Word Description
1 Compensation curve
mode
Space heating incorporating outdoor ambient temperature compensation
2 COP Coefcient of Performance the efciency of the heat pump
3 Heat pump Abbreviations for Water/Brine source heat pump
Indoor unvented DHW tank and component plumbing parts
4 DHW mode Domestic hot water heating mode for showers, sinks, etc
5 Flow temperature Temperature at which water is delivered to the primary circuit
6 Freeze stat. function Heating control routine to prevent water pipes freezing
7 FTC Flow temperature controller, the circuit board in charge of controlling the water circuit
8 C.B. Controller board, the circuit board in charge of controlling the refrigerant and ambient loop
9 Heating mode Space heating through radiators or Underoor heating
10 Legionella Bacteria potentially found in plumbing, showers and water tanks that may cause Legionnaires disease
11 LP mode
Legionella prevention mode – a function on systems with water tanks to prevent the growth of legionella bacteria
12 PRV Pressure relief valve
13 Return temperature Temperature at which water is delivered from the primary circuit
14 TRV
Thermostatic radiator valve – a valve on the entrance or exit of the radiator panel to control the heat output
15 Brine Mixture of antifreeze and water
16 Module Casing with built-in refrigerant circuit
17 Ambient loop Piping between WTW and Local system 2
Filled with brine or water
18 Ambient temp./
Ambient temperature
Outdoor temperature
19 PICV Pressure Independent Control Valve
For safe and correct use, read this manual before installing the heat pump unit.
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Safety Notices
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Please read the following safety precautions carefully.
WARNING:
Precautions that must be observed
to prevent injuries or death.
CAUTION:
Precautions that must be ob-
served to prevent damage to unit.
This installation manual along with the user manual should be left
with the product after installation for future reference.
Mitsubishi Electric is not responsible for the failure of locally-supplied
parts.
• Be sure to perform periodical maintenance.
• Be sure to follow your local regulations.
• Be sure to follow the instructions provided in this manual.
MEANINGS OF SYMBOLS DISPLAYED ON THE UNIT
WARNING
(Risk of re)
This unit uses a ammable refrigerant.
If refrigerant leaks and comes in contact with re or
heating part, it will create harmful gas and there is risk
of re.
Read the OPERATION MANUAL carefully before operation.
Service personnel are required to carefully read the OPERATION
MANUAL and INSTALLATION MANUAL before operation.
Further information is available in the OPERATION MANUAL, IN-
STALLATION MANUAL, and the likes.
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Safety Notices
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WARNING
Mechanical
The heat pump unit must not be installed, disassembled, relocated, al-
tered or repaired by the user. Ask an authorised installer or technician. If
the unit is installed improperly or modied after installation, water leak-
age, electric shock or re may result.
The heat pump unit should be positioned on a hard level surface capable
of supporting its lled weight to prevent excessive sound or vibration.
Do not position furniture or electrical appliances below the unit.
The discharge pipework from the emergency devices of the heat pump
unit should be installed according to local law.
All such safety relief valve connections shall NOT be used for any other
purpose.
Only use accessories and replacement parts authorised by Mitsubishi
Electric ask a qualied technician to t the parts.
Electrical
All electrical work should be performed by a qualied technician accord-
ing to local regulations and the instructions given in this manual.
The units must be powered by a dedicated power supply and the correct
voltage and circuit breakers must be used.
Wiring should be in accordance with national wiring regulations. Connec-
tions must be made securely and without tension on the terminals.
Earth unit correctly.
General
Do not smoke during work and transportation.
Keep children and pets away from the heat pump unit.
Do not use the hot water produced by the heat pump directly for drinking
or cooking. This could cause illness to the user.
Do not stand on the units.
Do not touch switches with wet hands.
Annual maintenance checks on the heat pump unit should be conducted
by a qualied person.
Do not place containers with liquids on top of the heat pump unit. If they leak
or spill onto the heat pump unit damage to the unit and/or re could occur.
Do not place any heavy items on top of the heat pump unit.
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Safety Notices
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WARNING
When installing, relocating, or servicing the heat pump unit, use tools and pipe
components specically made for use with R32 refrigerant and use only the
specied refrigerant (R32) to charge the refrigerant lines. Do not mix it with any
other refrigerant and do not allow air to remain in the lines.
If air is mixed with the refrigerant, then it can be the cause of abnormal high pres-
sure in the refrigerant line, and may result in an explosion and other hazards.
The use of any refrigerant other than that specied for the system will cause me-
chanical failure or system malfunction or unit breakdown. In the worst case, this
could lead to a serious impediment to securing product safety.
In heating mode, to avoid the heat emitters being damaged by excessive-
ly hot water, set the target ow temperature to a minimum of 2ºC below
the maximum allowable temperature of all the heat emitters. For Zone2,
set the target ow temperature to a minimum of 5ºC below the maximum
allowable ow temperature of all the heat emitters in Zone2 circuit.
Do not install the unit where combustible gases may leak, be produced,
ow, or accumulate. If combustible gas accumulates around the unit, re
or explosion may result.
Do not use means to clean, other than those recommended by the man-
ufacturer.
The appliance shall be stored in a room without continuously operating igni-
tion sources (for example: open ames, an operating gas appliance or an
operating electric heater).
Do not pierce or burn.
Be aware that refrigerants may not contain an odour.
Pipe-work shall be protected from physical damage.
The installation of pipe-work shall be kept to a minimum.
Compliance with national gas regulations shall be observed.
The appliance shall be stored in a well-ventilated area where the room
size corresponds to the room area as specied for operation.
Keep gas-burning appliances, electric heaters, and other re sources (ig-
nition sources) away from the location where installation, repair, and oth-
er air conditioner work will be performed. If refrigerant comes into contact
with a ame, poisonous gases will be released.
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Safety Notices
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WARNING
Brine
The selection of the brine MUST be in accordance with the applicable leg-
islation.
Take sufcient precautions in case of brine leakage. If brine leaks, venti-
late the area immediately and contact your local dealer.
The ambient temperature inside the unit can get much higher than that of the
room, e.g. 70°C. In case of a brine leak, hot parts inside the unit can create
a hazardous situation.
The use and installation of the application MUST comply with the safety
and environmental precautions specied in the applicable legislation.
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Safety Notices
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CAUTION
Use clean water that meets local quality standards on the primary circuit
and ambient loop (When not using Brine).
The heat pump unit should be located indoors to minimise heat loss.
Remove as much air as possible from the primary and DHW circuits
Refrigerant leakage may cause suffocation. Provide ventilation in accord-
ance with EN378-1.
Be sure to securely t insulation around the piping. Direct contact with the
bare piping may result in burns or frostbite.
Never put batteries in your mouth for any reason to avoid accidental in-
gestion.
Battery ingestion may cause choking and/or poisoning.
Install the unit on a rigid structure to prevent excessive sound or vibration
during operation.
Do not transport the heat pump unit with water inside the DHW tank. This
could cause damage to the unit.
If power to the heat pump unit is to be turned off (or system switched off)
for a long time, the water should be drained.
If unused for a long period, before operation is resumed, DHW tank
should be ushed through with potable water, and sterilised accordinaly.
Preventative measures should be taken against water hammer, such as
installing a Water Hammer Arrestor on the primary water circuit, as direct-
ed by the manufacturer.
Do not use refrigerant other than R32 refrigerant.
Servicing shall be performed only as recommended by the manufacturer.
Use the following tools specically designed for use with R32 refrigerant.
The following tools are necessary to use R32 refrigerant. Contact your
nearest dealer for any questions.
Be sure to install circuit breakers. If not installed, electric shock may re-
sult.
For the power lines, use standard cables of sufcient capacity. Otherwise,
a short circuit, overheating, or re may result.
When installing the power lines, do not apply tension to the cables. If the
connections are loosened, the cables can snap or break and overheating
or re may result.
Be sure to ground the unit. Do not connect the ground wire to gas or wa-
ter pipes, lightning rods, or telephone grounding lines. If the unit is not
properly grounded, electric shock may result.
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Safety Notices
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CAUTION
Use circuit breakers (ground fault interrupter, isolating switch (+B fuse),
and molded case circuit breaker) with the specied capacity. If the circuit
breaker capacity is larger than the specied capacity, breakdown or re
may result.
Tools (for R32)
Gauge manifold Flare tool
Charge hose Size adjustment gauge
Gas leak detector Vacuum pump adapter
Torque wrench Electronic refrigerant charging scale
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Introduction
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Product specication
Model name EHWT17D-MHEDW
Nominal domestic hot water volume 170 L
Overall unit dimensions 1750 × 595 × 680 mm (Height × Width × Depth)
Weight (empty) 166 kg
Weight (full) 345 kg
Refrigerant R32
The amount of refrigerant 0.9 kg
Water volume of heating circuit in the unit *1 5.47 L
Water volume of ambient loop in the unit 3.16 L
Safety device
Water circuit
(Primary)
Control thermistor Heating 1 to 80°C
Pressure relief valve 0.3 MPa (3 bar)
Flow sensor Min. ow 5.0 L/min
DHW tank Control thermistor 40 to 70°C
Temperature/Pressure relief valve 90°C / 0.7 MPa (7 bar)
Immersion
heater Manual reset 85°C
Ambient loop Control thermistor −8 to 30°C
Flow switch Min. ow 5.5 L/min
Refrigerant
circuit
Control thermistor (High) −20 to 125°C
Control thermistor (Low) −40 to 90°C
Pressure switch 4.14 ± 0.1 MPa
Pressure sensor 0 to 5.0 MPa
Primary circuit circulating Pump DC motor
Sanitary circuit circulating Pump AC motor
Connections Water (Primary/DHW circuits) 28 mm compression primary circuit/
22 mm compression DHW circuit
Water (Ambient loop) 22 mm compression
Guaranteed
operating range
Ambient *2 0 to 35°C ( 80 %RH)
Water inlet temperature (Ambient loop) 10 to 30°C
Min. Water outlet temperature (Ambient loop) 4°C
Operating range
Heating Room temperature 10 to 30°C
Flow temperature 20 to 60°C
DHW 40 to 60°C
Legionella prevention 60 to 70°C
Flow rate range
Primary circuit Max. 27.7 L/min
Min. 7.1 L/min
Ambient loop Max. 24.0 L/min
Min. 7.2 L/min
DHW tank performance
Maximum allowable hot water temperature 70°C
Declared load prole L
Average climate
Water heating energy efciency class
A+
Time to reheat 70% of DHW tank to 65°C *4 19.3 min
Time to raise DHW tank temp. 15 to 65°C *4 22.8 min
Electrical data
Heat pump
Power supply
(Phase, voltage, frequency) ~/N 230 V 50 Hz
Breaker 16 A
Immersion heater *3
Power supply
(Phase, voltage, frequency) ~/N 230 V 50 Hz
Capacity 3 kW
Current 13 A
Breaker 16 A
Sound power level at W10W35 (EN12102) 38 dB(A)
<Table 3.1>
The purpose of this installation manual is to instruct competent persons how to safely and efciently install and commission the heat
pump unit system. The target readers of this manual are competent heating, plumbing and/or refrigeration engineers who have at-
tended and passed the requisite Mitsubishi Electric product training and have appropriate qualications for installation of an unvented
hot water heat pump unit specic to their country.
Technical Information
3
Optional extras
• Wireless Remote Controller PAR-WT50R-E
• Wireless Receiver PAR-WR51R-E
• Remote Sensor PAC-SE41TS-E
• Thermistor PAC-TH011-E
• High temperature thermistor PAC-TH012HT-E
• ecodan Wi-Fi Interface MAC-567IF-E1
• 2-zone kit PAC-TZ02-E
• Expansion vessel (12L) PAC-EVP12-E
*1 Volume of sanitary water circuit is not included in this value
*2 The environment must be frost-free.
*3 Do not t immersion heaters without thermal cut-out. Use
only Mitsubishi Electric service parts as a direct replace-
ment.
*4 Tested under BS7206 conditions.
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Technical Information
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Note: For parts not shown on this page, please refer to 'Circuit
diagram <Figure 3.2>'.
Component Parts
<Figure 3.1>
No. Part name
A DHW outlet pipe
B Cold water inlet pipe
C Water pipe (Space heating return connection (to heat pump))
DWater pipe (Space heating ow connection (from heat pump))
E
Water/Brine pipe (Ambient loop return connection (to heat pump))
F Water/Brine pipe (Ambient loop ow connection (from heat pump))
1 Control and electrical box
2 Main remote controller
3 Plate heat exchanger (Refrigerant - Primary circuit)
4 Low-pressure sensor
5 3-way valve
6 Manual air vent
7 Drain cock (Primary circuit)
8 Manometer
9 Pressure relief valve (3 bar) (Primary circuit)
10 Automatic air vent
11 Expansion vessel (Primary circuit) (Local supply)
12 Flow sensor
13 Strainer valve
14 Water circulation pump 1 (Primary circuit)
15 Pump valve
16 DHW tank
17
Plate heat exchanger (Primary circuit (water) - Sanitary circuit (water))
18 Scale trap
19 Water circulation pump (Sanitary circuit)
20 Immersion heater
21 Magnetic lter (Ambient loop) (Local supply)
22 Temperature and pressure relief valve
23 Drain cock (DHW tank)
24 Pressure relief valve (10 bar) (Ambient loop) (Local supply)
25 Flow water temp. thermistor (THW1)
26 Return water temp. thermistor (THW2)
27 DHW tank water temp. thermistor (THW5A)
28 DHW tank water temp. thermistor (THW5B)
29 Refrigerant liquid temp. thermistor (TH2)
30 Module
31 Drain pipe (Local supply)
32 Expansion vessel (Sanitary circuit (water)) *1
33 Isolating valve (Local supply)
34 Magnetic lter (Local supply) (Recommended)
35 PICV (Pressure Independent Control Valve) (Local supply)
36 Compressor
37 High-pressure sensor
38 Linear expansion valve
39 Charge plug
40 Liquid temp. thermistor (TH3)
41 Discharge temp. thermistor (TH4)
42 Ambient temp. thermistor (TH7)
43 Heat sink temp. thermistor (TH8)
44 Plate heat exchanger (Water/Brine - Refrigerant)
45 Drain cock (Ambient loop)
46 Inlet control group *1
47 Flow switch
48 Water inlet temperature (Ambient loop) thermistor (TH32)
49 Water outlet temperature (Ambient loop) thermistor (TH34)
50 Mufer
51 Drain cock (Sanitary circuit)
52 Filling loop (Ball valves, check valves and exible hose) *1
53 High-pressure switch
54 Compressor surface temperature (TH33)
*1 Supplied with UK model ONLY.
Please refer to PAC-WK02UK-E Installation Manual for more
information on accessories.
<Module>
<Overall>
Note:
For installation, make sure to install a suitably sized pri-
mary-side expansion vessel. (See gure 3.2 and 4.3.2 for
further guidance)
<Table 3.2>
AB
9
8
10
1
18
19
22
20
16
6
14
D
7
4
3
15
5
12
13
C
EF
17
51
30
37 5053
38
36
44
47
45
39
23
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