INSTALLATION AND OPERATION INSTRUCTIONS
1-18
SL 20-115 MODULATING GAS BOILER
the sl modulating series boilers are designed for use within a closed loop,
forced circulation, low pressure system. a 30 psi pressure relief valve (3/4” nPt)
is supplied for field installation at one of the locations shown in the following
illustrations. relief valve discharge piping must terminate between 6” (15cm) and
12” (30cm) above the floor or per local Code.
due to the various piping options available, positioning the pressure relief valve
can vary. When piping from either side, the relief valve is installed in the upper
port opposite the supply outlet, using the fittings provided.
Figure 21
if piping from both sides at the same time, a tee must be installed on either
supply outlet, immediately on exiting the boiler so that there is no possibility of
installing an isolation valve between the pressure vessel and the relief valve.
The bottom connection kit includes a header fitting that allows installation of both
the relief valve and the air vent in the top left hand port, as illustrated
Figure 22
order the bottom connection kit from iBC as Part #P-104a the kit includes supply
and return risers to bring the piping to the bottom of the boiler case, escutcheon
plates to secure and seal the pipes as they exit the case, an auto air vent and the
relief and vent header fitting. Follow the instructions that come with the connection
kit. instructions can also be accessed on line from www.ibcboiler.com
CAUTION
Installers should inquire of
local water purveyors as to
the suitability of their supply
for use in hydronic heating
systems.
If water quality is
questionable, a local water
treatment expert must
be consulted for testing,
assessment and, if required,
treatment.
Alternatively, water or
hydronic fluid of known
quality can be brought to the
site.
WARNING
During operation, the relief
valve may discharge large
amounts of steam and/or hot
water. Therefore, to reduce
the potential for bodily
injury and property damage,
a discharge line MUST be
installed that it:
1. is connected from the valve outlet
with no intervening valve and
directed downward to a safe point of
discharge.
2. allows complete drainage of both the
valve and the discharge line.
3. is independently supported and
securely anchored so as to avoid
applied stress on the valve.
4. is as short and straight as possible
5. terminates freely to atmosphere
where any discharge will be clearly
visible and is at no risk of freezing.
6. terminates with a plain end which is
not threaded.
7. is constructed of a material suitable
for exposure to temperatures of
375°F or greater.
8. is, over its entire length, of a pipe size
equal to or greater than that of the
valve outlet.
DO NOT CAP, PLUG OR OTHERWISE
OBSTRUCT THE DISCHARGE PIPE
OUTLET!
Figure 21: Relief piping with single side piping connections
Figure 22: Relief piping with dual side or bottom piping connections
