Danfoss Heat Recovery Unit provide the link
between a CO₂ refrigeration systems and the
heating installation. It is developed and designed
for recovery of waste heat from refrigeration
installations, where CO₂ is used as medium, to
heat supermarkets (hot tap water, heating, air
handling units) and enables selling surplus heat
back to the district heating network. Danfoss
HRU can be used in installations with different
external heat supply, such as District energy,
boiler or other heat source.
Characteristic:
• Heating demand: 22-540 kW
• Maximum recovered heat from C0₂ pack up
to 50-400kW
Two different solutions based on store size:
1. one- tank solution - for small stores up to 1500 m
2. two-tanks solution - for medium and large stores
Standard layout in 6 versions:
• indirect connection (type A2,A6) or directly
connection (type A4,A7).
• indirect connection (type A1) or connection
to DHU (type A3), designed for areas where it is
possible to sell heat to DHU network.
Maximum operating
parameters
Materials
Primary
Maximum permissible supply temperature, primary*90 °C
Maximum permissible operating pressure, primary10 bar
Rated pressure, primaryPN 10
Maximum permissible flow primary
Secondary heating
Maximum permissible temperature, secondary*90 °C
Maximum permissible operating pressure, secondary(A1, A2) – 6 bar, (A3, A4, A6, A7) – 10 bar
Minimum required pressure (static), water supply 1,0 bar
Maximum permissible flow secondary
CO heat supply
Maximum permissible temperature secondary90 °C
Maximum permissible operating pressure, secondary(A1, A2) – 6 bar, (A3, A4, A6, A7) – 10 bar
Minimum required pressure (static), water supply1,0 bar
Circuit diagram A1Indirect connection to DHU network with possibility of transfer heat outside heating system
Twotanks solution
1DH supply
2DH return
DN40
*
DN40
3Heating supply
4Heating return
5Supply from
cooling unit
Return to
cooling unit
DN40
DN40
7DH supply
DH return
* Connections DH⁄HE: up to 216 KWDN 40 up to 337 kWDN50 up to 540 kWDN65
*
A1 selection list
CO2 output [kW] (sales demand)
up to
100
up to
150
up to 22146B9108146B9109
up to 54146B9120146B9121146B9122146B9123
up to 85146B9126146B9127146B9128146B9129
up to 135146B9132146B913314 6B9134146B9135
[kW]
up to 216146B9138146B9139146B9140146B9141
up to 337146B9144146B9145146B9146146B9147
Heating demand
up to 54014 6B9150146B915114 6B915214 6B9153
FunctionWaste heat from CO system is transferred via
CO heat exchanger * using water as medium,
into supply storage tanks T2 and T1.
The temperature sensor (S6) check the
temperature in tank (T2) and send a signal to
a 3-way valve (M1), which will open and heat
accumulated in tanks will be transferred into the
heating circuit.
Lower demand for heat will cause closing of the
controlling valve (M2) and reduce or cut the need
for energy from the external heat source. The
temperature sensor (S8) control the pump (P3)
and when the temperature reaches the desired
level and no more heat can be accumulated.
Secondary heat meters (F1 and F2) are measuring
flow and heat meter F3 on the charging circuit
calculates the recovered energy.
up to
300
up to
400
The primary function is to recover as much
energy as possible and secondary as high
temperature as possible
We always prioritize usage of heat
recovered from cooling unit before
supplying from external heat source
A1 version offers returning heat back into
the DHU network or other external network
via heat exchanger HEX2
If the recovered energy is more than the
stores can reuse the pump P4 is activated
so this energy can be sold to the district
heating
* CO₂ HEX is not included in the d elivery of HRU, but is part of the coolin g unit
VD.MG.D2.02
Data sheet HRU – Heat Recovery Unit
Circuit diagram A2Indirect connection to DHU network
Twotanks solution
DN40*DN40*
1DH supply
2DH return
3Heating supply
4Heating return
5Supply from
cooling unit
Return to
cooling unit
DN40
* Connections DH⁄HE: up to 216 KWDN 40 up to 337 kWDN50 up to 540 kWDN65
A2 selection list
CO2 output [kW]
up to 100up to 150up to 300up to 400
up to 135146B9164146B9165
up to 216146B9168146B9169146B9170
up to 33714 6B9173146B9174146B9175146B9176
Heating
up to 540146B9179146B9180146B9181146B9182
demand [kW]
FunctionWaste heat from CO₂ system is transferred via
CO₂ heat exchanger * using water as medium,
into supply storage tanks T2 and T1.
The temperature sensor (S6) check the
temperature in tank (T2) and send a signal to
a 3-way valve (M1), which will open and heat
accumulated in tanks will be transferred into the
heating circuit. Lower demand for heat will cause
closing of the controlling valve (M2) and reduce
or cut the need for energy from the external heat
source.
The temperature sensor (S8) controls the pump
with PWM signal (P3) and when the temperature
reaches the desired level and no more heat can
be accumulated.
In two-tanks solution application, secondary
heat meters (F1 and F2) are measuring flow and
heat meter F3 on the charging circuit calculates
the recovered energy.
* CO₂ HEX is not inclu ded in the delivery of H RU, but is part of the cooling uni t)
The primary function is to recover as much
energy as possible, and secondary as high
temperature as possible.
We always prioritize usage of heat recovered
from cooling unit, before supplying from
external heat source.
Circuit diagram A3Direct connection to DHU network with possibility of transfer heat outside heating system
Twotanks solution
1DH supply
2DH return
3Heating supply
DN40*DN40*
4Heating return
5Supply from
Cooling unit
Return to
cooling unit
7DH supply
DN40DN40
DH return
* Connections DH⁄HE: up to 216 KWDN 40 up to 337 kWDN50 up to 540 kWDN65
A3 selection list
CO2 output [kW] (Sales demand)
up to
100
up to
150
up to 22 146B9191146B9192
up to 54146B920314 6B9204146B9205146B9206
up to 85146B9209146B9210146 B9211146B9212
up to 135146B9215146B9216146B9217146B9218
[kW]
up to 216146B9221146B9222146B9223146B9224
up to 337146B9227146B9228146B9229146B9230
Heating demand
up to 540146B9233146B9234146B9235146B9236
FunctionWaste heat from CO system is transferred via
CO heat exchanger * using water as medium,
into supply storage tanks T2 and T1.
The temperature sensor (S6) check the
temperature in tank (T2) and send a signal to
a 3-way valve (M1), which will open and heat
accumulated in tanks will be transferred into the
heating circuit.
Lower demand for heat will cause closing of the
controlling valve (M2) and reduce or cut the need
for energy from the external heat source. The
temperature sensor (S8) control the pump (P3)
and when the temperature reaches the desired
level and no more heat can be accumulated.
Secondary heat meters (F1 and F2) are measuring
flow and heat meter F3 on the charging circuit
calculates the recovered energy.
up to
300
up to
400
The primary function is to recover as much
energy as possible and secondary as high
temperature as possible
We always prioritize usage of heat recovered
from cooling unit before supplying from
external heat source
A3 version offers returning heat back into the
DHU network or other external network via
heat exchanger HEX2
If the recovered energy is more than the
stores can reuse the pump P4 is activated so
this energy can be sold to the district heating
* CO₂ HEX is not included in the d elivery of HRU, but is part of the coolin g unit
VD.MG.D2.02
Data sheet HRU – Heat Recovery Unit
Circuit diagram A4Direct connection to DHU network
Twotanks solution
1DH supply
2DH return
3Heating supply
DN40*DN40*
4Heating return
5Supply from
Cooling unit
Return to
cooling unit
7DH supply
DH return
* Connections DH⁄HE: up to 216 KWDN 40 up to 337 kWDN50 up to 540 kWDN65
DN40
A4 selection list
CO2 output [kW]
up to 100up to 150up to 300up to 400
up to 13514 6B9247146B924 8
up to 216146B925114 6B9252146B9253
up to 337146B9256146B925714 6B9258146B9259
Heating
up to 540146B9262146B9263146B926414 6B9265
demand [kW]
FunctionWaste heat from CO₂ system is transferred via
CO₂ heat exchanger * using water as medium,
into supply storage tanks T2 and T1.
The temperature sensor (S6) check the
temperature in tank (T2) and send a signal to
a 3-way valve (M1), which will open and heat
accumulated in tanks will be transferred into the
heating circuit. Lower demand for heat will cause
closing of the controlling valve (M2) and reduce
or cut the need for energy from the external heat
source.
The temperature sensor (S8) controls the pump
with PWM signal (P3) and when the temperature
reaches the desired level and no more heat can
be accumulated.
In two-tanks solution application, secondary
heat meters (F1 and F2) are measuring flow and
heat meter F3 on the charging circuit calculates
the recovered.
* CO HEX is not included in the delivery of HRU but is part of the cooling unit
The primary function is to recover as much
energy as possible, and secondary as high
temperature as possible.
We always prioritize usage of heat recovered
from cooling unit, before supplying from
external heat source.
Circuit diagram A6Direct connection to DHU network with possibility of transfer heat outside heating system
Onetank solution
1DH supply
2DH return
3Heating supply
4Heating return
5Supply from
Cooling unit
Return to
cooling unit
A6 selection list
CO2 output [kW]
up to 100
up to 22 146B940 0
up to 54146B9401
Heating
up to 85146B94 02
demand [kW]
FunctionWaste heat from CO₂ system is transferred via
CO₂heat exchanger * using water as medium,
into supply storage tank T2. The temperature
sensor (S6) check the temperature in tank (T2)
and send a signal to a 3-way valve (M1), which
will open and heat accumulated in tank will
be transferred into the heating circuit. Lower
demand for heat will cause closing of the
controlling valve (M2) and reduce or cut the
need for energy from the external heat source.
The temperature sensor (S8) control the pump
with PWM signal (P3) and when the temperature
reaches the desired level and no more heat
can be accumulated. In one-tank solution
application, heat meter F3 on the charging circuit
calculates the recovered energy.
The primary function is to recover as much
energy as possible, and secondary as high
temperature as possible.
We always prioritize usage of heat recovered
from cooling unit, before supplying from
external heat source.
* CO₂ HEX is not included in the d elivery of HRU, but is part of the coolin g unit
VD.MG.D2.02
Data sheet HRU – Heat Recovery Unit
Circuit diagram A7Direct connection to DHU network
Onetank solution
1DH supply
2DH return
3Heating supply
4Heating return
5Supply from
Cooling unit
Return to
cooling unit
A7 selection list
CO2 output [kW]
up to 100
up to 22146B9403
up to 54146B940 4
Heating
up to 85146B9405
demand [kW]
FunctionWaste heat from CO₂ system is transferred via
CO₂heat exchanger * using water as medium,
into supply storage tank T2. The temperature
sensor (S6) check the temperature in tank (T2)
and send a signal to a 3-way valve (M1), which
will open and heat accumulated in tank will
be transferred into the heating circuit. Lower
demand for heat will cause closing of the
controlling valve (M2) and reduce or cut the
need for energy from the external heat source.
The temperature sensor (S8) control the pump
with PWM signal (P3) and when the temperature
reaches the desired level and no more heat
can be accumulated. In one-tank solution
application, heat meter F3 on the charging circuit
calculates the recovered energy.
The primary function is to recover as much
energy as possible, and secondary as high
temperature as possible.
We always prioritize usage of heat recovered
from cooling unit, before supplying from
external heat source.temperature as possible.
We always prioritize usage of heat recovered
from cooling unit, before supplying from
external heat source.
VD.MG.D2.02
* CO₂ HEX is not included in the d elivery of HRU, but is part of the coolin g unit