Single Wall Heat Exchanger; Freeze Protection - Raypak RSIT30 Installation & Operating Instructions Manual

Single-Wall Heat Exchanger
This Indirect fired water heater uses a single-wall heat
exchanger. In order for this water heater to meet the re-
quirements of the Uniform Plumbing Code, the following
requirements must be met.
1. The boiler water pressure must be limited to 30 PSI.
An approved 30 PSI relief valve must be installed
in the boiler loop.
2. The boiler heat transfer medium must be either
potable water or use fluid additives that have a tox-
icity rating of Class 1.
3. Bear a label on the system with the Wording "Cau-
tion" followed by:
a. The heat transfer medium must be water or
other nontoxic fluid having a toxic rating of
Class 1 as listed in clinical Toxicology of Com-
mercial Products, 5th ed.
b. The pressure of the heat-transfer medium must
be limited to a maximum of thirty (30) psig
(207kPa) by an approved safety or relief valve.

Freeze Protection

The water heater and water lines must be protected
from exposure to freezing temperatures. Freezing tem-
peratures can cause damage to this indirect water
heater. The unit should be located indoors.
If the water heater is to remain idle for an extended pe-
riod of time, the power and water to the boiler system
should be turned off to conserve energy and prevent a
build-up of dangerous hydrogen gas.
The water heater and piping should be drained if they
might be subjected to freezing temperatures.
After a long shut-down period, the water heater's oper-
ation and controls should be checked by qualified serv-
ice personnel. Make certain the water heater is
completely filled again before placing it in operation.
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