Specifications

19
7.1 Codes
See boiler manual for information pertaining to installation
in State of Massachusetts.
System incorporates gas-fi red, direct vent, condensing
appliances and must be installed in accordance with the
following:
Fuel Gas:
United States: Installation shall conform to National •
Fuel Gas Code (NFPA-54/ANSI Z223.1).
Canada: Installation shall be in accordance with CSA-•
B149.1 and B149.2 installation codes.
Authority having jurisdiction•
Electrical:
United States: National Electrical Code (ANSI/NFPA-•
70).
Canada: CAN/CSA-C22.1 Canadian Electrical Code.•
Authority having jurisdiction•
Condensate Disposal:
Authority having jurisdiction•
Installers:
Authority having jurisdiction•
Follow recommended maintenance outlined in this •
manual.
Grid Interconnection:
Authority having jurisdiction with respect to •
interconnecting to grid.
7.2 System Sizing And Application
Select system with proper capacity before continuing •
installation. Firing rate of system should be greater
than or equal to calculated peak heating load (heat
loss) for building or area(s) served by system. See
Section 2 for system ratings.
Base heat loss calculations on approved industry •
methods.
Confi gure hydronic • freewatt PLUS System with Zone
2 operated by Smart Zone HAI thermostat supplied
with freewatt PLUS System. Zone 2, Smart Zone,
must have suffi cient thermal load to provide proper
operation of MCHP unit. Too small of heat load in
Smart Zone will result in frequent MCHP cycling and
poor electrical power savings. The “Smart Zone” should
be selected as zone with largest heating demand (but
not domestic hot water zone). Normally, this would
be largest space heating zone on fi rst fl oor of two
story home. freewatt PLUS System will produce
best electric power generation benefi t if Smart Zone
represents about 25% of total home heating load.
Consider combining zones to achieve desired heat
load for Smart Zone if there is no single large zone in
existing distribution system but many small zones.
freewatt PLUS • System must be applied with hydronic
heating systems having ample heat delivery capacity
relative to maximum or design heat load. This is
requirement for freewatt PLUS and all high-
effi ciency hydronic systems to achieve maximum
energy effi ciency. “Under-radiated” system requiring
high supply water temperature (above 180°F) during
outdoor low-temperature design conditions will result
in reduced contribution of MCHP to total heat delivery,
reducing electrical power production benefi t. Preferred
design operating temperature is 160°F. Consider
adding additional heat radiation to existing under-
radiated distribution systems for proper application of
freewatt PLUS .
Power generation performance of • freewatt PLUS
System may be adversely affected if there is any zone
resulting in constant active call for heat during heating
season (i.e., highly under-radiated zone). Verify all
zones have enough radiation, even during very cold
weather, so no zone thermostat will produce continuous
call for heat (i.e., cannot be satisfi ed).
freewatt PLUS • requires different ECR zone relay
controls depending on type of zoning utilized: zoned
by circulators, valves, or air handlers. Verify you
have correct ECR zone relay control before beginning
installation.
7 - BEFORE INSTALLING THE SYSTEM