Gas Booster Location And Mounting (Where Applicable); Water Pipes; Water Supply; Hot Water Delivery Temperature - Rinnai PRESTIGE Operation & Installation Manual

INSTALLATION & MAINTENANCE - ALL SYSTEMS

GAS BOOSTER LOCATION AND MOUNTING (where applicable)

The gas booster is designed for 'Outdoor' Installation only. As such, it must be located in an above
ground open air situation with natural ventilation, without stagnant areas, where gas leakage and
products of combustion are rapidly dispersed by wind and natural convection.

WATER PIPES

All hot water pipework should be insulated with sealed Polyethylene foamed or equivalent insulation
to optimise performance and energy efficiency. Such insulation may also be mandatory under local
regulations. With the exception of solar collector flow and return pipes, water pipe sizing should be
performed in accordance with AS/NZS 3500.
The collector flow and return pipes should be a minimum of 15 mm copper tube.
Plastic pipe must not be used. Plastic pipe is not suited to the high water
temperatures and pressures that may occur in the collector flow and return
WARNING
system.
The maximum recommended combined lengths of the solar flow and return pipes are as follows:
Table 5 - Collector Flow and Return Pipe Sizing
Pipe Size
DN 15 (metres)
DN 20 (metres)

WATER SUPPLY

The minimum and maximum water pressures for the various systems are listed in Table 2. 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 separate Warranty document. 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.

HOT WATER DELIVERY TEMPERATURE

Local regulations and/or the requirements of AS/NZS3500.4 must be considered regarding the
temperature limitations of hot water supplied to areas used primarily for personal hygiene. The
temperature of water to these areas is limited to 45°C for early childhood centres, primary and
secondary schools and nursing homes or similar facilities for young, aged, sick or people with
disabilities and 50°C for all other buildings. To comply with these requirements, a temperature
limiting device, such as a thermostatic mixing or tempering valve, will be required on all solar hot
water systems as detailed in Figures 9 and 10.
Storage
cylinder
Cold water supply
Figure 9 - Tempered gas hot water systems
Rinnai Australia
1 Collector
60
Not recommended
Rinnai gas continuous
flow water heater for
solar applications,
preset to deliver
hot water at a fixed
temperature of 60°C or higher
Gas boost
Kitchen Laundry Ensuite Bathroom
TLD
Note: TLD = Temperature Limiting Device
- 18 - Solar Split Systems Operating / Installation Manual - Version 8 - 18/10/10
2 Collectors
50
60
Electrically
boosted
storage
cylinder
Cold water supply
Figure 10 - Tempered Electric hot water systems

3 Collectors
30
40
Kitchen Laundry Ensuite Bathroom
TLD
Note: TLD = Temperature Limiting Device