Technical data

8.0 Installation
25
8.9 Fitting a Room Thermostat
1. To fit a 2-wire thermostat, remove link and wire
the thermostat switch between positions 1 & 2
(Figs. 30 or 31a). A cable clamp is provided for
incoming cables.
8.10 Fitting a Baxi Intellistat
1. Refer to the Baxi Intellistat instructions.
2. The boiler installation parameters must be set to
recognise that the Intellistat will operate in
conjunction with the boiler (see section 10.6).
8.11 Fitting a Frost Thermostat
1. The frost thermostat is connected between
positions 1 and 4 (Figs. 31 or 31a). Secure the
incoming cable/s with the cable clamp and replace
the cover.
8.12 Fitting an Additional Pump
1. To extract 100,000 Btu/hr from the boiler in
central heating mode an additional pump will need
to be fitted to the system. Connect pump Live to
terminal 5 and use any available neutral.
8.13 Electrical System Checks
1. Earth Continuity Check: Isolate the appliance
at mains supply. Using a multimeter set to ohm’s
scale, test between any appliance earth point and
the earth pin on the socket. The resistance should
be less than 1ohm. If the resistance is greater than
1 then check all earth wires for continuity and
ensure that all connections are clean and tight.
WARNING: If the resistance is still greater than
1ohm the fault still exists and it may be
dangerous to work with the appliance live.
2. Short Circuit Check: Isolate the control
system, set all switches and thermostats to calling
for heat. Set the meter on ohm’s scale. Test from L
to N on control system terminal block - if the
resistance reads zero there is a short circuit.
3. Resistance to Earth Check: Isolate the control
system, set all switches and thermostats to calling
for heat. Set the meter on ohm’s scale. Test
between L and E - the resistance should be
greater than 1 mega ohm.
4. Polarity Check: If all the tests carried out so far
are satisfactory, then reconnect the system to the
mains supply. Set the meter on Volts AC scale
(starting at the highest voltage).Test at terminals:
L and N - meter should read approx 240 Vac
L and E - meter should read approx 240 Vac
N and E - meter should read from 0 to 15 Vac
5. Fuse Check: Remove the fuse, and check
resistance. There should be no resistance or
maximum reading. If no reading is obtained
change the fuse. Check fuse is 3A.
Filter
NL
Isolator
N L
1LN 234 5
External
Timer
Room
Thermostat
Optional Live Feed For
An External Pump
Fig. 30
Filter
NL
Isolator
N L
1LN 234 5
Frost
Thermostat
Fig. 31
Optional Live Feed For
An External Pump
Mains Input
Mains Input
Filter
NL
Isolator
N L
1LN 234 5
External
Timer
Room
Thermostat
Optional Live Feed For
An External Pump
Fig. 30a
Mains Input
Filter
NL
Isolator
N L
1LN 234 5
Frost
Thermostat
Fig. 31a
Optional Live Feed For
An External Pump
Mains Input
L