Piping Requirements; Pressure Relief Valve Requirements - Rinnai RL75I Operation And Installation Manual

Piping Requirements

• A manual water control valve must be placed in the
water inlet connection to the Rinnai water heater
before it is connected to the water line. Unions may
be used on both the hot and cold water lines for
future servicing and disconnection of the unit.
• The piping (including soldering materials) and
components connected to this appliance must be
approved for use in potable water systems.
• Purge the water line to remove all debris and air.
Debris will damage the Rinnai water heater.

Pressure Relief Valve Requirements

• An approved pressure relief valve is required by the
American National Standard (ANSI Z21.10.3) /
Canadian Standard (CSA 4.3) for all water heating
systems, and shall be accessible for servicing.
• The relief valve must comply with the standard for
Relief Valves and Automatic Gas Shutoff Devices
for Hot Water Supply Systems ANSI Z21.22 and /or
the standard Temperature, Pressure, Temperature
and Pressure Relief Valves and Vacuum Relief
Valves, CAN1-4.4.
• The relief valve must be rated up to 150 psi and to
at least the maximum BTU/hr of the appliance.
• The discharge from the pressure relief valve should
be piped to the ground or into a drain system to
prevent exposure or possible burn hazards to
humans or other plant or animal life. Follow local
codes. Water discharged from the relief valve could
cause severe burns instantly, scalds, or death.
• The pressure relief valve must be manually
operated once a year to check for correct operation.
Freeze Protection
The freeze protection features include electrical
heating elements. Freeze protection may be disabled
if electricity is not supplied, or if there is an error
preventing the water heater from functioning. Loss of
freeze protection may result in water damage from a
burst heat exchanger or water lines.
The installation of auto drain down solenoid valves is
optional. However, Rinnai strongly recommends that
these valves be installed to prevent damage from
freezing in case the normal freeze protection should
become disabled. Any product damage due to
freezing will not be covered by the warranty.
In addition, the solenoid valves should be connected
electrically to a surge protector with terminals. This
allows the solenoid valves to operate if the water
heater is disabled due to an error code.
• Toxic chemicals such as those used for boiler water
treatment are not to be introduced to the potable
water used for space heating.
• If the appliance will be used as a potable water
source, it must not be connected to a system that
was previously used with a nonpotable water
heating appliance.
• Ensure that the water filter on the Rinnai water
heater is clean and installed.
• The relief valve should be added to the hot water
outlet line and near the hot water outlet according to
the manufacturer's instructions. DO NOT place any
other type valve or shut off device between the relief
valve and the water heater.
• Do not plug the relief valve and do not install any
reducing fittings or other restrictions in the relief line.
The relief line should allow for complete drainage of
the valve and the line.
• If a relief valve discharges periodically, this may be
due to thermal expansion in a closed water supply
system. Contact the water supplier or local
plumbing inspector on how to correct this situation.
Do not plug the relief valve.
• Neither Rinnai nor the American National Standard
(ANSI Z21.10.3) / Canadian Standard (CSA 4.3)
requires a combination temperature and pressure
relief valve for this appliance. However, local codes
may require a combination temperature and
pressure relief valve.
The solenoid valves and surge protector with terminals
are available for purchase at Rinnai.
The freeze protection features will not prevent the
external piping from freezing. Rinnai recommends
heat tracing and insulating hot and cold water pipes
connecting units. Pipe cover enclosures may be
packed with insulation for added freeze protection.
With electrical power supplied, Rinnai water heaters
will not freeze when the outside air temperature is as
cold as –22ºF (-30ºC) for indoor models or is as cold
as –4ºF (-20ºC) for outdoor models, when protected
from direct wind exposure. Because of the "wind-chill"
effect, any wind or circulation of the air on the unit will
reduce its ability to freeze protect.
VB Series Indoor LS Manual 21