Basic System Piping Arrangements - IBC SL 14-115 G3 Installation And Operating Instructions Manual

WARNING
Do not use automotive-type
ethylene or other types of
automotive glycol antifreeze,
or undiluted antifreeze of
any kind. This may result in
severe boiler damage. It is the
responsibility of the Installer to
ensure that glycol solutions are
formulated to inhibit corrosion
in hydronic heating systems
of mixed materials. Improper
mixtures and chemical additives
may cause damage to ferrous
and non-ferrous components
as well as non-metallic, wetted
components, normally found
in hydronic systems. Ethylene
glycol is toxic, and may be
prohibited for use by codes
applicable to your installation
location. For environmental
and toxicity reasons, IBC
recommends only using non-
toxic propylene glycol.
1-24
SL 14-115 G3, SL 20-160 G3, SL 30-199 G3 MODULATING GAS BOILERS SL 14-115 G3, SL 20-160 G3, SL 30-199 G3 MODULATING GAS BOILERS
Figure 32: Important primary-secondary piping details with closely-spaced tees
The SL series modulating boilers offer exceptional matching of heat generation to
radiation. The low minimum firing is better suited to low thermal loads presented in a
typical multi-zoned radiation system. However, where individual zones in a heating system
have loads under 10,000 Btu/hr, the system will still benefit through use of a buffer tank to
ensure a controlled supply temperature, and to prevent short cycling. Buffering should be
added on the secondary piping of the relevant load, to avoid bulking up the thermal mass
of the primary piping circuit (and potentially lengthen the duration of the transition from hot
to cool loads).
SL modulating series boilers can be connected directly to a floor of non-oxygen barrier
polybutylene material (PB tubing). For maintenance of warranty on such systems, we
require evidence of a thorough flushing of all loops, plus installation of a dirt separator
or side stream filter. A separator/filter maintenance routine shall be carried out after the
retrofit, with filter clearing after the 1st day, 1st week, month and annually thereafter. Care
is to be taken to avoid use of ferrous fittings and pumps on Non Oxygen Barrier tube
systems.

1.6.2 Basic System Piping Arrangements

Primary / Secondary piping - Benefits and installation rules
1. Good circulating water flow through the boiler irrespective of load or radiation system
head
2. Allows flexible ΔT° control in secondary loops
3. Adds to the system's thermal buffering, to assist in handling small loads and
temperature transition.
A Primary / Secondary piping configuration requires an extra pump, independent from any
secondary load pumps. The SL series modulating boilers' controller hosts wiring terminals
and integral relays to simplify installation and operation of this preferred layout, offsetting
such costs.
For optimal performance, place pumps on the supply side of secondary loops to facilitate
air evacuation. Use pumps with internal check valves to avoid ghost flows and thermal
siphoning.
INSTALLATION AND OPERATION INSTRUCTIONS