13
4 - WATER CONNECTIONS
4.12 ENERGY RECOVERY - OPTION
Partial energy recovery
The use of a desuperheater makes it possible to recover, free
of charge, the heat that would otherwise be dispersed in the
environment. The partial heat recovery is composed of shell
and tube heat exchangers suitable for recovery of 25% of the
heat power dispersed by the unit (cooling and electrical power
of the compressors). If the temperature of the water to be
heated is relatively low, it is advisable to insert in the plumbing
circuit an adjustment valve to keep the recovery inlet tempera-
ture greater than 35°C to prevent condensation.
Ev
C
Vm
Fa
Bc
D
Ve
SL
F
VL
EWi
EWo
Ae 35 °C
12 °C
7 °C
RWo 45 °C
RWi 40 °C
C
Key
Ae fresh air
Bc condensing coil
C compressor
D heat partial recovery
Ev evaporator
EWi cooled water inlet
EWo cooled water outlet
F dryer filter
Fa fan
RWi partial recovery water inlet
RWo partial recovery water outlet
SL spia del liquido
Vc valve for condensing coil
enabling
Ve electronic expansion valve
VL cock on the liquid line
Vm cock on the supply line
Vr valve for total recovery
enabling
Recupero energetico totale
The use of total heat recovery may be the optimal solution in
all cases that require the production of hot water for medium
and large potentials. The production of hot water is always of
lesser priority than the production of chilled water. The total
heat recovery is composed of shell and tube heat exchangers
suitable for recovery of 100% of the heat power dispersed by
the unit (cooling and electrical power of the compressors). The
unit with total recovery is capable of managing the recovery
temperature with thermal adjustment integrated in the micro-
processor with two steps. The adjustment of power is mana-
ged based on chilled water and may have the following instan-
ces:
1) Cold request 100%, hot request 0% = circuit active only
cold,
2) Cold request 100%, hot request 100% = circuit active in
cold + recovery,
3) Cold request 50%, hot request 100% = circuit active in
cold+recovery (in this case the unit can provide only 50% of
the requested heat).
With the recovery active the condensing coil (Bc) is deactiva-
ted and condensation takes place in the total recovery (R).
Ev
C
Vm
Fa
Bc
R
Ve
SL
F
VL
EWi
EWo
Ae 35 °C
12 °C
7 °C
RWo 45 °C
RWi 40 °C
Lr
Vr Vc
Ev
C
Vm
Fa
Bc
R
Ve
SL
F
VL
EWi
EWo
Ae 35 °C
12 °C
7 °C
RWo 45 °C
RWi 45 °C
Lr
Vr Vc
C
With the recovery setpoint met, the condensing coil (Bc) is
reactivated, to perform condensation, via the solenoid valves
(Vr=off and Vc=on). In this case the recovery (R) acts as a
simple desuperheater.
In the plumbing circuit, considering the powers involved, it is
advisable to insert a storage tank with suitable capacity to
prevent constant commutations of the unit.
To Next Page
Loading...
Need help?
General