Ariston A/27 MFFI Water Connections, Pipe Work, By-pass, System Design, Safety Valve Discharge

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2.9Water Connections

A/23 MFFI - A/27 MFFI

A

B

C

D

E

I

Fig. 2.4

Legend

A = Central Heating Flow

B = Domestic Hot Water Outlet

C = Gas Inlet

D = Domestic Cold Water Inlet

E = Central Heating Return

I = Safety Valve

Central Heating

Detailed recommendations are given in BS 6798:1987 and BS 5449-1:1990, the following notes are given for general guidance.

Pipe Work:

Copper tubing to BS EN 1057:1996 is recommended for water pipes. Jointing should be either with capillary soldered or compression fittings.

Where possible pipes should have a gradient to ensure air is carried naturally to air release points and water flows naturally to drain taps.

The appliance has a built-in automatic air release valve, however it should be ensured as far as possible that the appliance heat exchanger is not a natural collecting point for air.

Except where providing useful heat, pipes should be insulated to prevent heat loss and avoid freezing.

Particular attention should be paid to pipes passing through ventilated spaces in roofs and under floors.

By-pass:

The appliance includes an automatic by-pass valve, which protects the main heat exchanger in case of reduced or interrupted water circulation through the heating system, due to the closing of thermostatic valves or cock-type valves within the system.

System Design:

This boiler is suitable only for sealed systems. Drain Cocks:

These must be located in accessible positions to permit the draining of the whole system. The taps must be at least 15mm nominal size and manufactured in accordance with BS 2870:1980.

Safety Valve Discharge:

The discharge should terminate facing downwards on the exterior of the building in a position where discharging (possibly boiling water & steam) will not create danger or nuisance, but in an easily visible position, and not cause damage to electrical components and wiring.

The discharge must not be over an entrance or a window or any other type of

B023

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Contents Mffi A/27 Mffi Table of Contents General Instructions General InformationMffi Technical InformationOverall View Mffi A/27 Mffi Reference Standards Siting the Appliance InstallationClearances Overall DimensionsMounting the Appliance Electrical ConnectionGas Connection Water Connections Safety Valve DischargePipe Work By-passFlue Connections Mains Water Feed Central HeatingFilling Terminal Position B023 Coaxial System Room Thermostat Connection Colours Electrical DiagramB023 Mffi Commissioning Water Circuit DiagramInitial Preparation Filling the Heating SystemRemoving the Front Panel Control PanelSelector Knob for Summer/Winter/Flue Analysis Modes Checks to be run before initial start-up are as follows Initial Start-up Operational AdjustmentsIgnition Failure Circulation FailureOverheating Safety Shut-off GAS AdjustmentsDraining the System Limescale Build-upChanging the Type of Gas MaintenanceMiscellaneous Wiring Diagram for Two Heating ZonesBlue Wiring Diagram for Connection to Ariston Unvented CylinderB023 B023 B023 Manufacturer Merloni TermoSanitari SpA Italy Cod 99 84 1260 112 B023