20
Mexico Super RS485 - RS4125 -
Installation & Servicing
INSTALLATION
25 FROST PROTECTION
WARNING.
Whilst effecting the required gas soundness test and purging air from the gas installation,
open all windows and doors, extinguish naked lights and
DO NOT SMOKE.
A.
ELECTRICAL INSTALLATION
1.
Checks to ensure electrical safety should be carried out
by a competent person.
2.
ALWAYS carry out preliminary electrical system checks,
i.e. earth continuity, polarity, resistance to earth and
short circuit using a suitable test meter.
27 COMMISSIONING AND TESTING
Central heating systems fitted wholly inside the house do not
normally require frost protection as the house acts as a 'storage
heater' and can normally be left at least 24 hrs. without frost
damage. However, if parts of the pipework run outside the house or
if the boiler will be left off for more than a day or so then a frost 'stat
should be wired into the system.
This is usually done at the programmer, in which case the
programme selector switches are set to OFF and all other controls
MUST be left in the running position.
The frost 'stat should be sited in a cold place but where it can
sense heat from the system.
Wiring should be as shown, with minimal disturbance to other
wiring of the programmer.
Designation of the terminals will vary, but the programmer and
thermostat manufacturer's leaflets will give full details.
Diagram A
shows a double pole frost thermostat, which should
suffice for all systems which do not use the OFF terminals of the
programmer.
26 FITTING THE CASING
1.
Offer up the RH side panel, locating it with the peg in the
baseplate, and push the panel back.
2.
Secure the panel to the baseplate and collector hood.
3.
Repeat steps 1 and 2 to refit the LH side panel.
4.
Place the top panel and push back.
5.
Secure the top panel to the side panels.
IMPORTANT.
Wiring within the boiler casing must be neatly secured
with the cable straps provided and MUST NOT be allowed to touch the
burner front plate, or the cleanout cover and the collector hood.
6.
Reconnect the in-line connector to the PCB lead and the Burner
On neon cable to the control panel.
MEX 219
6
5
7.
Replace the control box cover and refit the control panel using
the screws previously removed.
8.
Insert the thermostat phial and phial retaining clip into the
thermostat pocket. Take care not to kink the thermostat capillary
as it is unwound and secure it with the split pin as shown.
9.
Refit the grille assembly
Thermostat phial
Thermostat pocket
Phial retaining
clip
Split pin
MEX 729
Diagram B
shows a 'change-over' frost thermostat, which will
cover most systems which do use CH OFF. If, however, on
such a system the HW pipework is in an isolated part of the
house, a second frost thermostat may be used to protect it.
If in doubt, ask your installer for advice.
B.
GAS INSTALLATION
1.
The whole of the gas installation, including the meter,
MUST be inspected and tested for soundness, and
purged in accordance with the recommendations of
BS. 6891. In IE refer to I.S.813:2002.
2.
Purging air from the gas installation may be expedited by
loosening the union on the gas service cock on the boiler
and purging until gas is detected.
3.
Retighten the union and check for gas soundness.
The Benchmark Log Book or equivalent self certification should be completed and signed to demonstrate compliance
with Building Regulations.
INST
ALLA
TION
200942-1.p65
3/4/2004, 9:24 AM
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