Installing A Valve Kit; Pressure Relief Valve - Rinnai E110CN Installation & Servicing Instructions Manual

6.5.3

Installing a valve kit

A means to isolate the domestic plate heat exchanger for cleaning must be provide
at installation. Refer to figure 10 for proper piping layout. A Rinnai valve kit can be
used on domestic water connections for all combi boilers to allow for cleaning of the
plate heat exchanger 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 flat plate heat exchanger in areas where
water quality issues exist, as well as improve overall product serviceability
6.5.4

Pressure relief Valve

- An approved pressure relief valve is required by Rinnai for all water heating
systems.
- 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.
- The relief valve should be added to the hot water outlet line according to the
manufacturer 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.
- Rinnai does not require a combination temperature and pressure relief valve for
this appliance. However local codes may require a combination temperature and
pressure relief valve.
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