Install Instructions

17
Boiler Piping
Closed-Type Expansion Tank
It is recommended to pitch any horizontal pip-
ing upwards toward the expansion tank 1 inch
per 5 feet [2.5cm / 1.5 M] of piping. Use 3/4”
piping to the expansion tank to allow air with-
in the system to rise.
DO NOT install automatic air vents on a
closed-type expansion tank system. Air
must remain in the system and be
returned to the expansion tank to pro-
vide an air cushion. An automatic air
vent would cause air to be vented from
the system resulting in a water-logged
expansion tank.
Circulator
The CHALLENGER must be supplied with a
Central Heating (CH) circulator. The circulator
when wired directly to the CHALLENGER
will allow for domestic hot water priority and
to provide circulation for the freeze protection
feature of the boiler control. See Graph 5-10 on
page 80-82 for pressure drop and minimum
flow rate through the boiler.
Sizing Primary Piping
See Fig. 7 and 8, page 20, for recommended
piping arrangements based on various applica-
tions. Size the piping and system components
required in the space heating system, using rec-
ognized design methods.
System Piping - Zone Circulators
Connect the CHALLENGER to the system
piping as shown in Fig. 7 page 20 when zoning
with zone circulators.
The installer must provide a separate circulator
for each zone of space heating.
To ensure an adequate flow rate through
the CHALLENGER, the boiler supply
and return piping size must be a mini-
mum of 1 inch.
System Piping - Zone Valves
Connect the CHALLENGER to the system pip-
ing as shown in Fig. 8 page 20 when zoning with
zone valves. The primary / secondary piping
ensures that the boiler loop has sufficient flow.
To ensure an adequate flow rate through
the CHALLENGER, the boiler supply
and return piping size must be a mini-
mum of 1 inch.
CAUTION
NOTICE
NOTICE