Natural Gas To Lpg Conversion - Vaillant ecoTEC plus Instructions For Installation And Servicing

6 Natural gas to LPG conversion

6 Natural gas to LPG conversion
The ecoTEC plus is able to be field adjusted for use on
LPG – propane G31 gas. To enable conversion the use
of a combustion analyser is necessary.
Caution!
After converting from natural gas to LPG,
commission and check boiler function as
described in commissioning section of the
servicing and installation instructions.
Caution!
This conversion must only be carried
out by a competent person in accordance
with the Gas Safety (Installation and Use)
Regulation 1998. In the UK CORGI registered
installers undertake the work to
a safe and satisfactory standard.
Before starting any work.
Isolate the electrical supply to the boiler.
Turn off the gas supply at the gas service cock fitted
to the appliance.
Turn the gas valve "A" throttle screw (Ref fig.6.1) fully
clockwise.
Turn the "A" throttle screw back anti-clockwise the
required number of turns as stated in Table 9.1 for the
boiler installed.
Ensure the gas analyser is set to the correct fuel
setting propane.
To obtain conversion follow the procedure as listed
below.
Ensure that the gas supply pressure is = 34mbar.
The gas inlet working pressure can be checked at the
pressure test point on the gas valve (fig 5.3.).
Turn gas supply on.
Ensure there is an external heat demand.
Enter the test programs by holding the "+" key, see fig
6.2. and turning power on.
Press "+" until "P.1" is displayed for max rate.
Press " i " to operate appliance in this mode.
Allow appliance to stabilise.
Measure the CO at the combustion products test
2
point, see fig 9.1.
Check CO value (for case off) as stated in table 6.1 for
2
the boiler installed.
If required, using a screwdriver, adjust the "A" throttle
to obtain correct value. (rotating anti-clockwise to
increase).
Appliance will remain in this mode for 15 minutes or
exit by pressing " i " and "+" simultaneously.
Repeat the process above and select "P.2" for min
rate.
Press " i " to operate appliance in this mode.
Allow appliance to stabilise.
Check CO value (for case off) as stated in table 9.1 for
2
the boiler installed.
If required, using a 2mm allen key, adjust the "B"
offset to obtain correct value. (rotating clockwise to
increase)
After checking the combustion, exit by pressing " i "
and "+" simultaneously
Refit the chassis panel and the inner case.
(Note the CO will increase slightly).
2
28
NAT.GAS G20
CASE OFF CASE ON
CO % CO %
2 2
ecoTEC
plus 415 9.1+0.2-0.5 9.3+0.2-0.5 10.1+0.5-0.5 10.3+0.5-0.5
ecoTEC
plus 418 9.1+0.2-0.5 9.3+0.2-0.5 10.1+0.0-1.0
ecoTEC
plus 428 9.1+0.2-0.5 9.3+0.2-0.5 10.5+0.3-0.8 10.7+0.3-0.8
ecoTEC
plus 438 8.8+0.2-0.5 9.0+0.2-0.5 9.8+0.2-0.8 10.0+0.2-0.8
Table 6.1
Fig. 6.1 Gas control valve
Fig. 6.2 ecoTEC plus controls
PROPANE G31
CASE OFF CASE ON THROTTLE
CO % CO % ADJUSTMENT
2 2
5 TURNS
10.3+0.0-1.0 5 TURNS
5 TURNS
8 TURNS
"A" throttle –
"Pmax" rotate
to increase
"B" offset adjustment
"Pmin" rotate
to increase
Installation and Servicing ecoTEC plus