Switch Sequence Diagram; Boiler Control; Introduction - REMEHA Gas 310 ECO Technical Information

8.5 Switch sequence diagram

Air pressure differential check
1
Pre-ventilation
2
Burner start
3
Forced part load
4
Release modulating operation
5
Safety shut off valve
Ignition
Air pressure differential switch (LDS)
Flue fan
Butterfly valve
Heat demand
Flue gas damper (option)
fig. 19 Switch sequence diagram
04.31H.79.00003

8.6 Boiler control

8.6.1 Introduction

The Remeha Gas 310 ECO can be controlled using one
of the following methods:
Note: when using on/off control the boiler will also
modulate to maintain the flow temp set point (param-
eter !)
- Fully modulating, where the output modulates
between the minimum and maximum value on the
basis of the flow temperature defined by the modulat-
ing controller.
- Analog control (0-10 volts), where the heat output or
temperature is controlled by a 0-10 volt signal.
- On/ off control, (one-volt free relay) where the heat
output modulates between the minimum and maxi-
mum value on the basis of the flow temperature set in
the boiler.
- High/ low control, (two volt free relays) where the
boiler is controlled by means of a 2-stage controller at
part load and full load.
In all cases, modulation is based on the required flow
temperature and there is a dT dependent output control
with the following characteristic.
Up to a dT of 25° (factory setting, parameter H) the
boiler operates at full output. Between dT
the output reduces in linear fashion (see fig. 20).
load
62560.indd 25 62560.indd 25
100
80 1
2
60
3
40
4
20
0
0 50 100
0 50 100
fig. 20
pdf
and dT
full load part
25
5
150 200 250
time (in seconds)
150 200 250
time (in seconds)
Output control characteristic
300 350 400
300 350 400
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