Technical information

The secret of City Multi heat
recovery systems lies in the
BC Controller
How does the R2 / WR2 Heat Recovery System operate
on 2 Pipe’s?
The BC Controller houses a liquid/gas separator, allowing the
outdoor unit to deliver a mixture (2 phase) of hot gas for heating
and liquid for cooling, all through the same pipe. Three pipe systems
allocate a pipe to each of these phases. When this mixture arrives
at the BC Controller, it is separated and the correct phase delivered
to each indoor unit depending on the individual requirement of
either heating or cooling.
Why R410A?
R410A is a more efficient refrigerant as it has a higher specific
heat capacity when compared to R407c or R22. This higher
energy carrying capacity allows for smaller pipe sizes, longer pipe
runs and reduces the volume of refrigerant within a system.
This is a major factor when complying with EN378, a
European standard concerning safety and environmental
requirements in the design, manufacture, installation,
operation, maintenance and disposal of refrigerating systems.
Comparison
example of piping
connection sites
= 2 sites
= 3 sites
Why Heat Recovery?
Flexibility and efficiency are key factors when selecting a heat
recovery system. For example, while a heat pump system is
adequate for a large open plan office, businesses that have a
more partitioned structure to an office will require the need
to simultaneously heat or cool different sections of the office
according to each users individual preferences.
The efficiency of this type of system comes from the ability to
use the by-products of cooling and heating to transfer energy
where it is required, thus acting as a balanced heat exchanger
achieving up to 20% cost savings over a conventional heat
pump system.
The number of connection sites needed for a R2 / WR2
system are also significantly lower than those needed for a
three pipe version. This helps to reduce installation costs,
further increasing the savings associated with City Multi.
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