R3400 Technical data - Rendamax

Rendamax
Type ∆T 20 K Pump data
Nominal
flow
rate
Boilerresistance
Grundfos
Pump type
Pump
speed
Head
at
Qnom.
Available
head at
Qnom.
Max.*
power
consumption
m 3 /h kPa kPa kPa W
R3401 28.54 46 UPS 65-120F 3 77 31 1.15
R3402 31.63 53 UPS 65-120F 3 69 16 1.15
R3403 37.00 36 UPS 65-120F 3 54 18 1.15
R3404 41.84 43 UPS 80-120F 3 70 27 1.50
R3405 46.75 50 UPS 80-120F 3 62 12 1.50
R3406 51.60 58 LM 80-160/162 - 70 12 1.50
R3501 26.36 37 UPS 65-120F 3 80 43 1.15
R3502 30.83 25 UPS 65-120F 3 72 47 1.15
R3503 34.87 30 UPS 65-120F 3 60 30 1.15
R3504 38.96 35 UPS 80-120F 3 75 40 1.50
R3505 43.00 40 UPS 80-120F 3 68 28 1.50
R3601 26.36 37 UPS 65-120F 3 80 43 1.15
R3602 30.83 25 UPS 65-120F 3 72 47 1.15
R3603 34.87 30 UPS 65-120F 3 60 30 1.15
R3604 38.96 35 UPS 80-120F 3 75 40 1.50
R3605 43.00 40 UPS 80-120F 3 68 28 1.50
Table 12
Water flow rate and pump data
* The maximum power consumption of the pump is given for pump speed 3. The optimum operating point in relation to
efficiency and minimum power consumption can be determined from the related pump curve.
The primary pump has been sized to have an optimum duty when ∆T = 20 K. When running at ∆T’s
less than 20 K the pump size should be checked to ensure suitability.
The water flow rate can be adjusted with the aid of the built-in 3-speed pump control. The water
flow rate can be measured by making a ∆P measurement via the filling and drainage valve in the
supply and return pipe of the unit. The measured head can be compared with the boiler resistance
(table 12). At full capacity the water flow rate can be very accurately compared with the ∆T, measured
acros the flow and return of the boiler.
The unit has a standard pump control. When the boiler is en abled, the pump is switched on. When
the enable signal is removed, the pump will continue to run for several minutes. This run on time
is adjustable. The standard time is two minutes.
y
When the system includes air heaters (ventilation, air treat ment), it is usually desirable to have a
small ∆T over these components. Because of this, the quantity of water flowing through the total
secondary circuit is usually greater than that flowing through the boiler units.
The low velocity header must be dimensioned such that the water speed does not exceed 0.5 m/s.
In this case the diameter of the header must be calculated for the water volume flowing through
the secondary circuit. When the water volume flowing through the secondary circuit is great er
than that flowing through the primary circuit, a mixed temper ature will exist which is lower than
the desired temperature of the supply from the appliance. The regulation system reacts to this
and opens the control devices (valves, etc.). Usually the supply temperature from the boiler(s)
must be adjusted to obtain the desired temperature in the connected circuits.
38 Doc890/3456CV02B