Water Quality And System Preparation; General; Anti-Freeze; Existing Installation (Primary Water Circuit) - Mitsubishi Electric EHST20C-VM6HB Installationshandbuch

4
installation

4.2 Water Quality and System Preparation

General

• Water quality should be to European Directive 98/83 EC standards.
► pH value of 6.5-8.0 (Recommended: pH6.5 - 7.5)
► Calcium ≤ 100 mg/l
► Chlorine ≤ 100 mg/l
► Iron/Manganese ≤ 0.5 mg/l
• In known hard water areas, to prevent/minimise scaling, it is beneficial to restrict
the routine stored water temperature (DHW max. temp.) to 55°C.

Anti-Freeze

Anti-freeze solutions MUST use propylene glycol with a toxicity rating of Class 1 as
listed in Clinical Toxicology of Commercial Products, 5th Edition.
note: ethylene glycol is toxic and must nOt be used in the primary water
circuit in case of any cross-contamination of the potable circuit.
new installation (primary water circuit)
• Before connecting outdoor unit, thoroughly cleanse pipework of building debris,
solder etc using a suitable chemical cleansing agent.
• Flush the system to remove chemical cleanser.
• For all packaged model systems add a combined inhibitor and anti-freeze
solution to prevent damage to the pipework and system components.
• For split model systems the responsible installer should decide if anti-freeze
solution is necessary for each site's conditions. Corrosion inhibitor however
should always be used.

existing installation (primary water circuit)

• Before connecting outdoor unit the existing heating circuit MUST be chemically
cleansed to remove existing debris from the heating circuit.
• Flush the system to remove chemical cleanser.
• For all packaged model systems add a combined inhibitor and anti-freeze
solution to prevent damage to the pipework and system components.
• For split model systems the responsible installer should decide if anti-freeze
solution is necessary for each site's conditions. Corrosion inhibitor however
should always be used.
When using chemical cleansers and inhibitors always follow manufacturer's
instructions and ensure the product is appropriate for the materials used in
the water circuit
How to access internal Components and Control and
electrical Box
<A> Opening the front panel
1. Remove the two lower screws.
2. Slide front panel upwards to slightly and open carefully.
3. Disconnect the relay connector connecting main controller cable and the control
board cable.
<B> Opening the control and electrical box cover
1. Remove the 4 screws.
2. Slide the control and electrical box cover upwards slightly and remove facing
panel.
<C> Accessing the back of the control and electrical box
The control and electrical box has 3 holding screws and is hinged on the left hand side.
1. Remove the holding screw on the control and electrical box.
2. The control and electrical box can then be swung forward on the left hand
hinges.
note:
1. Before accessing back of control and electrical box release cables from
the tie straps attached to the cross-support.
2. After servicing, re-secure all cables using straps provided. reconnect
main controller cable to its relay connector. replace front panel and re-
secure screws at base.
Minimum amount of water required in the space
heating circuit
Outdoor heat pump unit
Packaged model PUHZ-W50
PUHZ-W85
PUHZ-HW112
PUHZ-HW140
Split model PUHZ-RP35
PUHZ-RP50
PUHZ-RP60
PUHZ-(H)RP71
PUHZ-(H)RP100
PUHZ-(H)RP125
PUHZ-RP140
PUHZ-SW40
PUHZ-SW50
PUHZ-SW75
PUHZ-SW100
PUHZ-SW120
PUHZ-SHW80
PUHZ-SHW112
PUHZ-SHW140
SUHZ-SW45
<A>
Front
panel
Screws
<Figure 4.2.1>
Minimum water quantity [l]
40
60
80
100
32
40
50
60
80
100
120
32
40
60
80
120
60
80
100
40
<Table 4.2.1>
<B> <C>
Hinges
Screws
Screws
Open
Notice/
label
12