Water Pipes, Fittings And Insulation; Water Supply - Rinnai SG175 Operation & Installation Manual

INSTALLATION

WATER PIPES, FITTINGS AND INSULATION

The solar hot and solar cold pipes between the solar storage tank and the solar collectors must be
suited to the high water temperatures and pressures that may occur� As such, plastic pipe must not
WARNING be used� Components used to join pipes must use metallic materials to achieve sealing� The collector
flow and return pipes should be at least 15 mm copper tube.
Insulation
All hot water pipework should be insulated with sealed polyethylene foamed or equivalent insulation to optimise
performance and energy efficiency, and to protect against frost damage. Such insulation may also be mandatory
under local regulations�
Rinnai recommend insulation to achieve at least the R value shown in the following table�
Location of Installation
• CER Zone 4
• Areas defined as Evacuated Tube Only in the
latest version of the Rinnai Solar Hot Water
Warranty Booklet�
• Any other area prone to frost conditions�
• All other areas
All supplied insulation materials must be fitted as shown to minimise heat losses. In frost prone areas this insulation
will also protect against frost damage�
Pipe Sizing
With the exception of solar collector flow and return pipes, water pipe sizing should be performed in accordance
with AS/NZS 3500� All external pipework MUST be insulated to prevent frost damage�
The maximum combined lengths of the solar flow and return pipes are as follows:
Pipe Size
DN 15
DN 20

WATER SUPPLY

The maximum water pressures for the various systems are listed on page 12� Approved pressure limiting valves
may be required if the maximum rated water supply pressures are exceeded. For gas boosted systems to achieve
the rated flow through the outlet of the continuous flow water heater, the minimum water supply pressures must be
supplied. The systems will operate at lower pressures but the rated flow will not be achieved.
Water chemistry and impurity limits are detailed in the warranty booklet� Most metropolitan water supplies fall within
these requirements. If you are unsure about water quality, contact your water authority. If sludge or foreign matter
is present in the water supply, a suitable filter should be incorporated in the water supply to the storage cylinder.
Rinnai
1 Flat Plate Collector
EVT20A or EVT25A
40 metres
60 metres
Pipes on Roof Pipes on Roof
Flat Plate Evacuated
Collectors Tube Collectors
R = 1�0K�m²/W R = 1�0K�m²/W
R = 0�6 K�m²/W R = 1�0K�m²/W
2 Flat Plate Collectors
EVT30A or 2 x EVT20A
40 metres
60 metres
20
Pipe between
tank and gas
booster
R = 0�6 K�m²/W
R = 0�6 K�m²/W
3 Collectors
30 metres
40 metres
Split Solar OIM