NorAire EB-HPH Series, Installation & Operating Instructions Manual

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09/06/2018 2 BI903
NorAire Concept
NorAire
is an air source heat pump that produces hot water. NorAire takes heat energy from the outside air
and uses a refrigeration to water heat exchanger to transfer that heat energy into water, then distributed in a
variety of ways to heat your home.
What Makes NorAire Versatile?
NorAire is a highly efficient, intelligent multi-stage heating system
(ASHP, electric boiler and or external gas boiler). It monitors heat pump run time, outdoor temperature,
return temperature, outlet temperature, and a variety of potential system faults. It also monitors multiple
room thermostats, controls circulating pumps and stages in the various heating sources to operate either
together or independently, all while maintaining a comfortable temperature to the space, and maintaining a
high level of energy efficiency. An integrated 2-zone control allows for built-in system flexibility, including
the option to prioritize a zone and define the zone as high temperature electric boiler assist with priority
allowing one zone to service baseboard heat or indirect domestic hot water while using the other zone for
low temperature applications such as in-floor radiant heating. All of this is customizable via the product
display.
Operating Sequence
This represents a unique and very significant part of the NorAire Heat Pump Boiler philosophy and design.
The NorAire as a single package provides total heating comfort throughout the entire heating season. It does
this in a unique way where the heat loss requirement can be satisfied in one of three sequences. Below is a
walkthrough of this sequence. All settings and adjustments are made through the interactive display.
Sequence I
– At the start of a heat call, if the outdoor temperature is greater than lockout (adjustable via
product display), the heat pump portion of the NorAire will be called on to heat the space by itself. At the
same time, a timer is started and displayed on the LCD display (accessible via product display). This timer
signifies the amount of time the heat pump will run on its own.
Sequence II
– Continuing from the above sequence, if the heat pump portion of the NorAire alone does not
satisfy the original heat call (as noted above), the “Boost In” timer will expire causing the NorAire system to
shift into “Boost Mode”. This means the Electro-Boiler will be enabled to operate with the heat pump to heat
the space. Meaning they will work together or at the same time. “Boost Mode” will continue throughout the
remainder of the thermostat heat call (provided outdoor temperature is above lockout). During “Boost Mode”,
the NorAire controller will reference a variable known as “Differential Temperature” (accessible via product
display) to determine the “Boost Mode” desired temperature (DT). It will take the “Differential
Temperature” value and add it to the return temperature to formulate its desired temperature. While in “Boost
Mode”, you can monitor DT on the LCD display. You will see the boiler elements stage and module to
achieve and maintain this formulated DT. Example:

System is in “Boost Mode”

Return temp = 80°F

“Differential Temperature” setting = 10° (factory default)

Desired temperature will equal 90°F
As the space is heated, the return water temperature will tend to shift upward, DT will track along with this
shift.
Sequence III
– Outdoor temperature falls below lockout temperature. At this point, the NorAire controller
will shut the outdoor unit down and reference a variable known as “Heat Source Below Lockout”. This
variable determines which heat source to use to heat the space when outdoor temperature is below lockout
value. If this variable is set to “Electro-Boiler” (factory default), the built-in (or external) Electro-Boiler will
be the heat source selected. If the variable is set to “External Gas Boiler”, the external gas boiler is used to
heat the space.
NOTE:
Once the outdoor temperature drops below lockout and NorAire disables the outdoor unit and
transitions to whichever source is selected (Heat Source Below Lockout), a 4°F rise in outdoor temperature is
required before the NorAire controller will switch back to heat pump operation (Boost Mode)
during the
same heat call
.