Grundfos ALPHA2 User Manual

19
9. Systems with bypass valve between flow and return pipes
Contents:
9.1 Purpose of bypass valve
9.2 Manually operated bypass valve
9.3 Automatic bypass valve (thermostatically controlled).
9.1 Purpose of bypass valve
Fig. 11 Systems with bypass valve
Bypass valve
The purpose of the bypass valve is to ensure that the heat from the boiler
can be distributed when all valves in the underfloor-heating circuits and/or
thermostatic radiator valves are closed.
System elements:
• bypass valve
• flowmeter, pos. A.
The minimum flow must be present when all valves are closed.
The pump setting depends on the type of bypass valve used, i.e. manually
operated or thermostatically controlled.
9.2 Manually operated bypass valve
Follow this procedure:
1. Adjust the bypass valve with the pump in setting I (speed I).
The minimum flow (Q
min.
) for the system must always be observed.
Consult the manufacturer's instructions.
2. When the bypass valve has been adjusted, set the pump according to
7. Setting the pump.
TM03 8928 2707
A

Grundfos ALPHA2 Specifications

General

Max Head	8 m
Voltage	230 V
Frequency	50/60 Hz
Type	Circulator Pump
Max. operating pressure	10 bar
Series	ALPHA2
Connection Type	Threaded
Protection Class	IP42
Liquid Temperature Range	2°C to 110°C
Energy Efficiency Index	≤ 0.23
Connection size	G 1 1/2
EEI	≤ 0.23