Frost Protection; Circulating Pump; Anticycling 'Economiser' Control; Automatic Pump Spin Control (Aps) - Vaillant ecoTEC plus 612 Instructions For Installation And Servicing

4 Boiler installation sequence

5 Commissioning Part I

the room containing the room thermostat should not be
fitted with a TRV).
4.17

Frost protection

The boiler has an integral frost thermostat which is
designed for protection of the boiler. To protect remote
or exposed parts of the heating system or property addi-
tional frost protection measures must be taken such as
the installation of an external frost thermostat. This
frost thermostat should be connected across the boiler
terminals 3 and 4, in parallel with any external heating
controls.
Note
External frost protection cannot be used when
plug in timers are utilised.

4.18 Circulating pump

The boiler incorporates a built in circulating pump that is
fully prewired (no additional wiring is necessary). The
pump incorporates an automatic overrun period after
the boiler switches off.

4.19 Anticycling 'economiser' control

The boiler incorporates a built in anticycling control to
ensure that energy wasteful short cycling of the boiler
cannot occur. This control prevents the boiler from re-
igniting for a preset period after central heating opera-
tion (the hot water operation is unaffected by this con-
trol and hot water can be drawn at any time).
Note
To temporarily override the anticycling control
turn the main boiler on/off switch to the off
position "0" and then back to the on position
"I" after a few seconds.

4.20 Automatic pump spin control (APS)

The boiler incorporates a built in control which will spin
the built in circulating pump and operate the diverter
valve (ecoTEC combination boilers only) once in a 23
hour period. This control helps to prevent seizure when
the boiler is not operated for a period of time. This con-
trol is not active when the power supply to the appliance
is turned off.
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5 Commissioning Part I
5.1

Preliminary electrical checks

Check the electrical installation by carrying out short
circuit, earth continuity and resistance to earth tests and
a check for correct polarity.
5.2

Gas supply

The complete gas installation including the gas meter
must be inspected, checked for leaks and purged in
accordance with BS 6891. In IE the current edition of IS
813. The gas supply to the boiler can be purged by slack-
ening the gas service valve beneath the boiler. Ensure
that there is adequate ventilation, extinguish all naked
flames and do not smoke whilst purging. After purging,
the gas service valve connection must be retightened
and checked for leaks. (The boiler itself does not require
purging as this will be done by the automatic burner
sequence control).
5.3 Cold water supply (ecoTEC combination boilers
only)
Open all domestic hot water taps supplied by the boiler,
turn on the mains water supply to the boiler and open
the mains water isolating valve below the boiler. Water
will now flow through the boiler to the hot taps. Starting
with the lowest tap supplied, turn the hot taps off one at
a time until the hot water pipework is purged of air.
Check all hot and cold water pipework for leaks.
5.4

Filling and bleeding the heating system

Note
The P.6 test program is for filling the heating
system: The diverter valve (combination boilers
only) moves to the centre position, the pump
does not run and the appliance does not go into
heating mode. Use the test program as
described in Section 8.4.
The P.0 test program is for bleeding the hot
water circuit (as well as the DHW circuit on
combination boilers): The appliance does not go
into heating mode; the pump runs inttermit-
tently and bleeds the two circuits in succession.
Use the test program as described in Section
8.4.
Instructions for installation and servicing ecoTEC