Instruction manual

12
A INSTALLATION INSTRUCTIONS
3.2 Safety Relief Valve
An ASME approved safety relief valve, (set
at 30 psi), must be installed in a vertical
position on the outlet side of the central
heating system, and as close as possible to
the heater. There must be no valves between
the safety relief valve and the heater.
Manually operate the safety relief valve at
least once a year to ensure proper operation.
Precaution must be taken prior to operating
the safety relief valve, to avoid contact with
hot water coming out of the safety relief valve
and to prevent water damege.
If the safety 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 safety relief valve.
3.3 Heating Supply and Return
The central heating supply and return pipes
are marked with different colored caps,
(supply red and return blue).
If there are any heating elements above
heater level, it is advisable to install a check
valve on the supply pipe to prevent natural
circulation phenomena from occurring.
If the heater is to be connected to an existing
system it is advisable to wash out and remove
any deposits from inside the existing pipes,
and install a filter at the lowest point to trap
any additional impurities when it is running.
This equipment is designed for use in a closed
loop system.
Installation schematics are found in figures
23 to 28.
WARNING !!! All the schematics in figures
23 to 28 are only samplesl. Safety apparatus,
pipe diameters, and auxiliary accessories,
must be verified by a qualified personnel only
and in accordance with the national and/or
local codes.
3.3.1 Installation of two heaters
Iinstalling two heaters in parallel. Follow the
schema in the figure 23
3.3.2 Installation of three or more
heaters
Installing three or more heaters in parallel.
Follow the schema in the figure 24
3.3.3 Radiant heating installation
When the heater is used in conjuction with
radiant heating, it is imperative that the tubing
contains an oxygen diffusion barrier. If you
are unsure whether or not the tubing has a
barrier, a heat exchanger must be used to
protect the heater from oxygen corrosion (See
figure 25). This situation will also occur if the
heater is used on an open-loop system where
new, cold-fill water is introduced into the
system. The oxygen will remove itself from
solution and react chemically with the ferrous
components (i.e. steel), causing them to rust
and corrode. THIS TYPE OF FAILURE IS
NOT COVERED BY THE WARRANTY!
3.3.4 Used of glycol
If glycol is used with the heater, the glycol
must be recognized as safe or approved by
the United States Food and Drug
Administration for food contact as listed in
Code of Federal Regulations, title 21, part 182
of the Food Additive Regulations. Any
additives introduced into the heating system
must be recognized as safe by the United
States Food and Drug Administration. If a
non-approved additive is used, it can
cause serious health problems or possibly
death.The pressure of the heating system
side of the heater must be fitted with devices
(automatic water feed/pressure reducing
valve not to exceed 30 psi) arranged to
function automatically in order to maintain the
pressure of the heating side at a level below
that of the potable water leaving the heat
exchanger.
3.4 Domestic Hot and Cold water
The domestic hot water flow restrictor must be
installed on the cold water inlet, (Refer to figure
25, 26, 27 and 28).
For servicing purposes, install a shut-off valve
upstream from the cold water inlet.