Elson 170zd - Indirect Unit Installation Guide

12
SAFETY
DISCONNECTFROMTHEMAINSELECTRICAL
SUPPLYBEFOREREMOVINGANYCOVERS.
Never attempt to replace the immersion heater(s)
other than with the recommended authorised
immersionheater(s).
DO NOT BYPASSTHETHERMALCUT-OUT(S)
INANYCIRCUMSTANCES.Ensurethetwo
malespadeterminationsontheundersideofthe
combinedthermostatandthermalcut-outare
pushedrmlyontothecorrespondingterminations
ontheelementplateassembly.
Incaseofdifcultycontactservicesupport;contact
detailsavailableatthebackofthisbooklet.
ELECTRICALSUPPLY
Allelectricalwiringshouldbecarriedoutbya
competentelectricianandbeinaccordancewiththe
latestI.E.EWiringRegulations.
Each circuit must be protected by a suitable fuse
and double pole isolating switch with a contact
separation of at least 3mm in both poles.
Theimmersionheater(s)shouldbewiredin
accordancewithFig8.Theimmersionheaters
MUSTbeearthed.Thesupplycableshouldbe
1.5mm
2
3coreHOFRsheathedandmustberouted
throughthecablegripprovidedwiththeoutersheath
ofthecablermlysecuredbytighteningthescrews
onthecablegrip.
DO NOT operate the immersion heaters until the
cylinder has been lled with water.
Ensurethethermostatandthermalcut-outsensing
bulbsarepushedfullyintothepocketsontheelement
plateassembly.
PLUMBINGCONNECTIONS
Indirectcylindersrequirethefollowing
pipeworkconnections.
Coldwatersupplytoandfrominletcontrols.•
Outlettohotwaterdrawoffpoints.•
Dischargepipeworkfromvalveoutletsto•
tundish.
Connectiontotheprimarycircuit.•
Allconnectionsare22mmcompression.However,
3/4”BSPparallelthreadedttingscanbettedtothe
primarycoilconnectionsifrequired.
BOILERSELECTION
Theboilershouldhaveacontrolthermostatandnon
self-resettingthermalcut-outandbecompatiblewith
unventedstoragewaterheaters.
Whereuseofaboilerwithoutathermalcut-out
isunavoidablea“lowhead”openventedprimary
circuitshouldbeused.Thefeedandexpansion
cisternheadabovethecylindershouldnotexceed
2.5m.
PRIMARYCIRCUITCONTROL
The 2 port motorised valve supplied with the cylinder
MUSTbettedontheprimaryowtothecylinder
heat exchanger and wired in series with the indirect
controlthermostatandthermalcut-outttedtothe
unit.
Primary circulation to the cylinder heat exchanger
mustbepumped;gravitycirculationWILLNOT
WORK.
SPACEANDHEATINGSYSTEMSCONTROLS
The controls provided with the cylinder will ensure
thesafeoperationoftheunitwithinthecentral
heatingsystem.Othercontrolswillbenecessaryto
control the space heating requirements and times
thatthesystemisrequiredtofunction,seeFig.8
below.
Thecylinderiscompatiblewithmostheating
controls,examplesofelectricalcircuitsareshownin
Figs.9and10(Page13).However,othersystems
maybesuitable,refertothecontrolsmanufacturers’
instructions,suppliedwiththecontrolsselected,for
alternativesystemwiringschemes.
INSTALLATION - INDIRECT
L
N
1 2 3
Element Connections
1.5mm² 3 Core
HOFR sheathed
cable
Indirect control
wiring
Fig.8:Electricalconnections(indirectschematic)