Rinnai Q130SN, Installation & Servicing Instructions Manual

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Installation & Servicing Instructions Rinnai Q-Series
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6.5 Hot water supply (Combi boiler Q175CN/Q175CP)
Connection of the drinking water installation should be performed according to the
national secondary drinking water regulations.
Do NOT use toxic chemicals, such as are used for boiler treatment in potable
water heating systems used for space heating.
The sanitary water pipes can be connected to the installation by use of adapter
fittings. The cold water inlet on the Combi boilers must be equiped with the following
components (counted in the water flow direction):
Flow regulator valve (supplied), Safety group, Expansion vessel 87 PSI / 6bar (potable
water, blue).
A flow regulator valve is supplied with the boiler. The flow regulator valve ensures that
a quantity of water is supplied which has a outlet temperature of 120°F (assuming a
cold water temperature of 45°F). The quantity of water is virtually unaffected by the
water pressure. The 3/4" NPT adapter fitting with the flow reducing valve must be
fitted in the cold water connection (see Dimensions 5.3, cold water pipe -k).
When there is a water pressure lower than 22PSI / 1.5 bar it is advisable to
remove the inside mechanism of the flow reducing valve. Contact Rinnai for
removal instructions.
6.5.1 Domestic Water quality
Appropriate steps must be taken to ensure the indirect tank water heater does not
become plugged by scale caused by hard water or sediment. If the indirect tank water
heater becomes plugged by either scaling from hard water of sediment it is not the
responsibility of Rinnai.
1. Water hardness for DHW
When there is a water hardness of more than 6-7 grains hardness is used for domestic
water a water softener must be installed on the inlet side of the DHW connection.
2. Sediment in DHW
If there is sediment in your domestic water supply sediment filter or other suitable
device should be used to remove it before the water enters the indirect tank water
heater.
6.5.2 Installing a valve kit
A means to isolate the domestic indirect tank water heater for cleaning must be pro-
vide at installation. Refer to figure 11 for proper piping layout. A Rinnai valve kit can
be used on domestic water connections for all combi boilers to allow for cleaning of
indirect tank water heater and installation the domestic hot water pressure relief valve.
• Rinnai recommends the use of the MRIK-T (3/4” NPT thread connection) or MRIK-S
kit (MRIK-S (3/4” sweat connection) when connecting the domestic water lines to
the boiler.
• Use of this kit will assist in flushing the indirect tank water heater in areas where
water quality issues exist, as well as improve overall product serviceability.
NOTICE
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! DANGER