Installation Instructions For Gas Installer; Gas Connection; Gas Pressures; Gas/ Air Ratio Control - REMEHA Gas 310 ECO Technical Information

9

INSTALLATION INSTRUCTIONS FOR GAS INSTALLER

9.1 Gas connection

The Gas 310 is suitable for use with natural gas only.
The gas connection is at the top of the boiler (see fig.
02). The boiler is fitted with a gas filter as standard to
prevent dirt from contaminating the gas valve or burner
assembly. An isolating main gas cock must be installed
in the vicinity of the boiler.

9.2 Gas pressures

The boiler main gas valve can accept an inlet pressure
up to 30 mbars, but MUST have a Min of 17 mbar at
the gas filter inlet test point when the boiler is operating
at max output. Pressures below this level can result in
lockouts (for multi gas appliance installations this Min
pressure must be available at each boiler with all gas
appliances firing on max output).
Boilers with 7, 8 and 9 sections can also work with gas
pressures up to 100 mbar. In such case, the boiler has
to be adjusted for a corresponding CO
ances on gas arrival pressures are ± 5 mbar.
10

COMMISSIONING

10.1 Initial lighting

w
1. Isolate main power supply.
2. Remove the casings on the inspection side.
3. Open the main gas valve.
4. Check the electrical connections including earth.
5. Fill the boiler and the system with water
(approximate 1.0 bar).
6. Vent the system.
7. Fill the siphon with water.
8. Check the flue gas discharge connection and air
inlet duct or air supply connection.
9. Vent the gas pipe.
10. Open the gas cock to the boiler.
11. Check the inlet gas pressure PI (see fig. 23).
12. Check the gas connection for gas tightness.
13. Switch on the mains supply to the boiler.
14. Switch on the boiler operating switch.
15. Switch on the heating pump and check the
installation position and direction of rotation.
16. Adjust the boiler controls to heat demand.
17. The boiler should start with the run sequence
indicated in the code-display:
0 =
Boiler neutral position.
5 =
Butterfly valve opens, if connected;
Wait for minimum gas pressure switch to close;
Neutral position check of air pressure differential sensor;
Flue gas damper opens (if applicable);
The fan runs and the boiler waits until sufficient air
62560.indd 29 62560.indd 29
9.3
The boiler has a pressure differential gas/ air ratio
control. This gas/ air ratio control maintains the correct
balance of gas and air quantities to the burner at a con-
stant level under variable loads. This ensures clean and
reliable combustion and high part load efficiency across
the entire load range.
Minimum airflow is monitored before a start by an air
pressure differential sensor.
setting. Toler-
2
transport is established; the air pressure differential sen-
sor must switch to guarantee sufficient airflow.
t =
1 =
2 =
3 =
17.a
17.b
29

Gas/ air ratio control

Gas valve leak proving system (if applicable).
Pre-purging.
Heating pump starts running; Ignition of the gas/
air mixture.
The burner is firing.
Check and correct, if necessary, the boiler for
correct gas/air ratio set-up. Checking takes
place on full and part load, adjustment takes
place only on the gas valve multiblock. For
checking and adjusting are required: an elec-
tronical CO -gauge (on the basis of O
2
gas pressure gauge.
Note that the opening (see fig. 24) around the
measuring probe is sealed properly during
measurement.
Note also that measuring the O
flue gas is necessary, because direct measure-
ment of CO can lead to inaccuracies due to
2
varying CO levels in the natural gas.
2
Connect the gas pressure meter between meas-
uring point PG on the underside of the gas valve
multiblock and measuring point PL on the ven-
turi (see fig. 23), ensuring the connections are
gas tight.
Run the boiler at full load (forced mode 'high')
by pressing the m- and [+]-key simultaneously
for 2 seconds. The letter h will now appear on
the display.
) and a
2
levels in the
2
18-6-2009 13:14:58 18-6-2009 13:14:58