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 provide circulation for the freeze protec-
tion feature of the boiler control. See Graph 5-
10 on page 69-71 for pressure drop and mini-
mum 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