Grant GSD1 Differential Solar ControllerInstallation & User Instructions

Part No. DOC.94 Rev.01 November 2012

Solar Thermal

2

Co

nten

ts

Contents1 Introduction 3

2 Technical Specification 42.1 Technical data 4

2.2 Temperature sensors 4

2.3 Package contents 4

3 Controls and Operation 53.1 Description 5

3.2 Operating modes 5

3.3 Controller features 5

3.4 Pushbutton 5

3.5 Adjustment dial 6

3.6 Display selector switch 6

3.7 Display 7

3.8 Time of day 7

3.9 Day of the week 7

4 Operating Functions 84.1 Differential temperature 8

4.2 Collector temperature 8

4.3 Storage cylinder temperature 8

4.4 Collector switch-off 8

4.5 Collector cooling 8

4.6 Pump kick function 10

4.7 Heat quantity calculation (Calorimetry) 10

5 Installation 115.1 Mounting wall plate/wiring base 11

5.2 Electrical connection 11

5.3 Fitting controller 13

6 System 146.1 System operation 14

6.2 System type 14

7 Commissioning/Programming 157.1 Programming mode 15

7.2 Setting the controller 15

7.3 Parameter settings 16

7.4 Solar controller parameters 17

8 Fault Finding 188.1 Error messages 18

8.2 Checking for faults 18

Intr

od

ucti

on

3

1 IntroductionDear Customer, Thank you forpurchasing a Grant Solar ThermalSystem. This Installation manual mustbe read carefully before installing theGrant Solar Controller. We recommendthat before installing the system thatyou attend a training course at ourtraining centre.

The Grant GSD1 Mk2 Solar Controlleris a digital differential controller for basicsolar thermal systems using a singlepump station. It is not intended for usewith more complex solar thermalsystems, e.g. those using two or morepump stations and/or two or more hotwater storage vessels.

This controller is not intended to beused as part of a safety relevantthermal control circuit, or any other use,beyond the operation scope of thecontroller. Incorrect application of thecontroller could result in damage to thesystem, to property, or injury or deathto either the users of the system orthird parties. Grant Engineering UK Ltdshall not be liable for any injury ordamage arising from the incorrect useof this controller.

For correct usage, refer to theseinstallation and user instructions.

Installation of the Grant GSD1 Mk2Solar Controller must be installed by acompetent person in accordance withall current legislation, codes of practiceand local by-laws relating to theinstallation of solar thermal systems.

The electrical installation must complywith the requirements of the Electricityat Work Regulations 1989 andBS7671:2008 – IEE Wiring Regulations17th Edition (including all amendments).

All installation of Solar Thermal systemsmust comply with the relevant BuildingRegulations.

Pump type

The Grant GSD1 Mk2 controller issuitable for use with a 2-speed 230V50Hz solar circulating pump, as fitted tothe Grant Solar Thermal pump stations.For use with any other type of solarcirculating pump please contact theGrant Technical Department forassistance.

1 Introduction

The diagrams in these instructionsshow only the essential componentsin order to demonstrate thedescribed functions. They are notintended as complete diagrams tobe used for the design andinstallation of a system on site.

! NOTE

4

Tech

nica

lS

pec

ifica

tio

ns

2 Technical Specifications2.1 Technical Data

Figure 2-2: Wall plate/wiring base

Ambient Temperature range Operation 0 to 50°CStorage/transport -30 to 60°C

Degree of protection To EN60529 IP40

Protection Class To EN60730 II protected

Supply voltage 230V 50HZ

Power consumption 5 VA

2.2 Temperature Sensors

Temperature/resistance – Pt1000 Thermistor

Temp °C Resist Ω Temp °C Resist Ω Temp °C Resist Ω

-50 803 20 1078 90 1347-40 843 30 1117 100 1385-30 882 40 1155 110 1422-20 922 50 1194 120 1461-10 961 60 1232 130 14920 1000 70 1270 140 153610 1039 80 1309 150 1573

2.3 Package Contents

The Grant GSD1 Mk2 Solar Controller kit comprises the following items:

1 x Wall mounting plate/wiring base

1 x GSD1 plug-in controller unit

2 x Pt1000 temperature sensors

1 x Installation and User Instructions

Figure 2-1: Controller unit

Co

ntro

lsan

d O

per

atio

n

5

3.1 DescriptionThe Grant GSD1 Mk2 Solar Controlleris a digital differential temperaturecontroller. The purpose of a digitaldifferential temperature controller is toefficiently operate the solar circulatingpump when sufficient solar energy isavailable, whilst preventing unsafe hightemperatures in the hot water storagecylinder. Refer to Section 4 for details ofoperation.

The controller has an easily accessibledisplay mode and a passwordprotected programming mode (in whichthe parameters for operation of thesystem can be set).

The controller has different parametersby which the control of the system canbe adapted. The majority of theseparameters are factory set and do notneed to be adjusted. Only a smallnumber of parameters need to be setby the installer as part ofcommissioning the controller/system.

Refer to Section 7.3 for details of all thecontroller parameters and guidance onthose that have to be set by theinstaller.

3.2 Operating ModesThe controller has THREE differentoperating modes, as follows:

Off In this setting the pumpswitch contact (A1) ispermanently open and thesystem circulating pump isOFF – irrespective ofdifferential Temperaturesensing

Auto In this setting the controllerworks in normal operatingmode based on theparameter settings anddifferential temperature

Service This setting allows normaloperation of the controller tobe overridden forcommissioning or servicingwork

Note: After 30 minutes thecontroller will automaticallyswitch back to the Automode

To switch between these threeoperating modes briefly press thepushbutton (located below the displayon the controller). Refer to section 3.3for details.

3.3 Controller FeaturesThe controller has the following featuresfor setting the parameters andmonitoring operation of the system:

a) A backlit display screen

b) A display selector switch

c) A pushbutton for selecting theoperating mode

d) An adjustment dial

3.4 PushbuttonThe pushbutton has several functions,as follows:

a) To change the operating mode ofthe controller. Press the pushbutton briefly to switch betweenOff – Auto – Service

b) To access the programming mode. Press and hold the push button for2 seconds.

c) To exit the programming mode.Press and hold the push button for2 seconds.

3 Controls and Operation

Figure 3-1: Controller features

Selector switchDisplay

Push button Adjustment dial

6

Co

ntro

lsan

d O

per

atio

n

3 Controls and Operation3.5 Adjustment DialThis is used to change the value of aparameter when in the programmingmode. Turn the dial to select therequired value of the parameterconcerned. Turning the dial to the right(clockwise) increases the value and tothe left (anticlockwise) decreases thevalue. Press the pushbutton to set andapply that value.

3.6 Display Selector SwitchSetting the pointer of the selectorswitch to corresponding symbol allowsthe required value to be shown on thecontroller display, as follows:

Display Selector Switch Symbols

Display of the time in 24-hour format.

Display of collectortemperature (in °C) –Input E1.

Display of the storagecylinder temperature (in°C) – Input E2.

No values displayed –these inputs are not used.

Display of the energycollected during thecurrent day (in kWh).

Display of the total energycollected (in kWh).

Display of pump speed(%) – not used.

Figure 3-2: Display selector switch

To the leftdecreases value

To the rightincreases value

Co

ntro

lsan

d O

per

atio

n

7

Figure 3-3: Controller display Figure 3-4: Day of the week indication

3.7 DisplayDepending on the position of theDisplay Selector Switch, thecorresponding information is shownon the display.

In addition, the following system statusinformation is also displayed:

Flashing collectorindicates the system is instagnation. The storagecylinder has reached therequired temperature.No further heat can betransferred. The solarfluid in the collectorevaporates in a controlledway.

Switch A1 is closed andthe solar pump isoperating depending onthe collector and cylindertemperatures (when thecontroller is set to Autooperating mode).ORSwitch A1 is closed andthe solar pump isoperating due to thecontroller beingoverridden (when thecontroller is set toService operating mode).

Switch A2 is closed –due to controller override(when the controller is setto Service operatingmode).

Displayed value x1000.

The controller isswitched Off.

The controller is inAuto mode.

Pump kick function:Day function.

Pump kick function:Night function.

The controller is inService mode.

With controller in Automode: Analogue displayof the collectortemperature from 0°C to120°C. With controller inprogramming mode:A flashing displayindicates that theparameter displayed canbe adjusted (using theadjustment dial).

3.8 Time of dayWith the controller in either the Autoor Service mode, the current timeis displayed in 24-hour format.The time displayed can be alteredby adjusted Parameter P01 in theProgramming mode.

3.9 Day of the weekWith the controller in either the Auto orService mode, the current day of theweek is displayed as a bar below theinscription for the corresponding day ofthe week. Refer to Figure 4-1. The dayof the week displayed can be altered byadjusted Parameter P02 in theProgramming mode.

8

Op

erat

ing

Fun

ctio

ns

4 Operating Functions4.1 Differential temperatureThe Solar circulating pump is activatedby the controller when the temperaturedifference between the solar collector(s)and the solar part of the hot waterstorage cylinder exceeds the ‘switch-on’ temperature difference value (P20)of 6°C (6K).

When the temperature differencebetween the collector(s) and thestorage cylinder falls to ‘switch-off’value (P21) of 3°C (3K) the controllerwill stop the solar circulating pump.

This ‘switch-on’ temperature differenceand ‘switch-off’ temperature differenceparameters are factory set and shouldnot be adjusted unless advised to doso by the Grant Technical Department.

4.2 Collector temperatureProvided that the ‘switch-on’temperature difference is exceeded(see 4.1 – Differential temperature), thecollector temperature has to exceed thecollector minimum ‘switch-on’temperature (P30) of 20°C for thesolar controller to start the solarcirculating pump.

When the collector falls below thecollector minimum ‘switch-off’temperature (P31) of 15°C thesolar controller will stop the solarcirculating pump.

The minimum ‘switch-on’ temperature(P30) must always be higher than theminimum ‘switch-off’ temperature (P31)by a difference of 5°C (5K). Thesetemperature parameters are factory setand should not be adjusted unlessadvised to do so by the Grant TechnicalDepartment.

4.3 Storage cylindertemperatureThe maximum storage cylinder‘switch-on’ temperature (P62), for thesolar part of the hot water cylinder,is the maximum temperature up towhich the solar circulating pump isswitched on by the controller.

When the maximum storage cylindercharging temperature (P60) is reached,the solar circulating pump is switchedoff by the controller.

4.4 Collector switch-offWhen the maximum collector ‘switch-off’ temperature (P34) is exceeded, thesolar controller stops the solarcirculating pump. As the heat is nolonger transferred away from thecollector(s), a controlled vaporisation ofthe solar fluid takes place within thecollector(s). The solar circulating pumpcannot be switched back on until thetemperature in the collector falls belowthe maximum collector switch-ontemperature (P35).

The switch-on temperature parameteris factory set and should not beadjusted unless advised to do so bythe Grant Technical Department.

4.5 Collector cooling

The collector cooling function of thesolar controller delays the vaporisationof the solar fluid in the collectors.Shortly before reaching the maximumtemperature of the collector, thecontroller starts the solar pump to coolthe solar fluid using the heat losses inthe system pipework and hot waterstorage cylinder.

In order for the collector coolingfunction to operate, the maximumcollector ‘switch-off’ temperature (P34)must be set higher than the ‘switch-on’temperature of the collector coolingfunction (P32).

The working range of the collectorcooling function is set by ParameterP32 (Collector cooling ‘switch-on’temperature) and Parameter P33(Collector cooling ‘switch-off‘temperature). These temperatureparameters are factory set and shouldnot be adjusted unless advised to doso by the Grant Technical Department.

To meet the requirements ofApproved Document G - Part G3, atempering valve must be fitted to thehot water outlet of the cylinder.

! NOTE

This function is not used with GrantSolar Thermal Systems.

! NOTE

Op

erat

ing

Fun

ctio

ns

9

The solar circulating pump is switchedoff by the solar controller when thetemperature in the solar part of thestorage cylinder reaches themaximum storage cylinder chargingtemperature (P60).

Figure 4-1: System operating parameters

NORMAL OPERATINGPARAMETERS

COLLECTOR COOLINGPARAMETERS

Measured at collectorsensor E1P30=20°C Min collectorSwitch-on tempP31= 15°C Min collectorSwitch-off temp

Measured at cylindersensor E2P60=60°C Max cylindercharging tempP62=55°C Max cylinderswitch-on temp

Measured at cylindersensor E2P61=90°C Max storagecylinder temp

Measured at collectorsensor E1P32=115°C Switch-on tempP33=110°C Switch-off tempP34=120°C Max collectorswitch-off tempP35=105°C Max collectorswitch-on tempP20=6°C (K) Switch-on temp

diff (ΔT on)P21=3°C (K) Switch-off tempdiff (ΔT off)

E1

E2

10

Op

erat

ing

Fun

ctio

ns

4 Operating Functions4.6 Pump kick functionThis function is not used with GrantSolar Thermal systems and is factoryset to OFF (Parameter P76 is set to 0)and should not be adjusted unlessadvised to do so by the GrantTechnical Department.

When set to operate (i.e. whenParameter P76 in not set to 0), thesolar pump will automatically operatefor a short period (the ‘pump kickinterval’ – P76) at regular time intervals(the ‘pump kick break’ period – P75).As a result, if the sensor was in shade(and thus cooler than the rest of thecollector), the resulting flow over thesensor will enable it to detect the actualtemperature of the fluid in the collector.

If the temperature increase of thesensor is less than 0.5K then the solarcirculating pump is switched off again.After a further pump kick break period(P75) the process is repeated.

If, during the pump kick interval (whenthe solar circulating pump is running), atemperature increase of 0.5K ismeasured by the sensor the next pumpkick break is skipped (i.e. the solarpump continues to run).

This process is repeated until either:

a) The ‘switch-on’ conditions for thenormal operation of the solar thermalsystem are met, or

b) A temperature increase is no longermeasured by the sensor.

In order to optimise the powerconsumption of the solar circulatingpump used to provide this function,a time frame is set within which the asolar output is expected. This timeframe is defined by setting a‘switch-on’ time (P05) and a‘switch-off’ time (P06). The factoryset values for these two parametersare 7.00 (P05) and 22.00 (P06).

4.7 Heat quantity calculation(Calorimetry)The controller will measure the amountof heat energy collected based on thevalue of the flowrate (in litres/min)manually entered as Parameter P82.For this function of the controller tooperate Parameter P80 must be set to0. Refer to Section 7.3 – parametersettings.

The measurement of heat energycollected is based on:

a) The temperature of the hot flow –using the collector sensor (E1);

b) The temperature in the hot waterstore – using the storage cylindersensor (E2);

c) The type of heat transfer fluid –Parameter P85 (pre-set to 0 forPropylene Glycol);

d) The solar fluid concentration –Parameter P84 (pre-set to 40%);

e) The solar fluid flowrate (in litres/min)– Parameter P80 (actual flowrate seton pump station).

Depending on the setting of the DisplaySelector switch, either the Daily heatoutput or Total (cumulative) heat outputcan be displayed, based on the aboveparameters. Refer to Section 3.6.

IMPORTANT

Important. All the aboveparameters must be correctlyset in order for the controller tomeasure and display the amountof heat collected.

Inst

alla

tio

n

11

5 Installation IMPORTANT

Ensure the electrical supply tothe solar thermal system hasbeen isolated before fitting andconnecting the GSD1 solarcontroller.

5.1 Mounting wall plate/wiring baseSeparate the controller from the wallplate/wiring base by gently prising thetwo grips (one at each side of thecontroller) away from the controllerusing a small screwdriver. Refer toFigure 5-1. Carefully pull the controllerunit out from the wall plate wiring base.

Position the wiring base in the requiredlocation on a wall. Using the wiringbase as a template, mark and drill fourholes in the wall. Note: Only use thewiring base to mark the hole positionsand NOT as a drilling jig. Fix the wiringbase to the wall using suitable wallplugs and screws (not provided).

5.2 Electrical connectionThe inside of the wiring base is dividedinto three sections – refer to Figure 5-2.All 230V mains electrical connectionsare situated in the left hand sectionand all the connections for thetemperature sensors are situated inthe right hand section.

Insert screwdriver blade and twist

Figure 5-1: Removal of controller

Carefully prise controller out fromwiring base Figure 5-2: Wiring base terminals

12

Inst

alla

tio

n

5 Installation

The broken line shown betweenterminals 3 and 10 in Figure 5-2indicates an internal connection.NO wire link should be fittedbetween these two terminals.

! NOTEMake the electrical connections to thewiring base as follows:

a) Fit a link wire (minimum crosssection 1.5mm²) between Terminal 1on the left hand (Live) terminal barand the Neutral (N) terminal block.

b) Fit a link wire between Terminal 15on the Right hand (sensor) terminalblock and the Ground (GND)terminal block.

c) Connect the 230V mainspower supply.Live to Terminal 2.Neutral to Neutral terminal block (N).Earth to Earth terminal block.

d) Connect the 230V output to thesolar pump.Live to Terminal 5.Neutral to Neutral terminal block.Earth to Earth terminal block.

e) Connect the Collector sensor.One wire to Terminal 16.One wire to Ground terminalblock (GND).There is no polarity for sensorconnections.

f) Connect the Cylinder sensor.One wire to Terminal 17.One wire to Ground terminalblock (GND).There is no polarity for sensorconnections.

Refer to Figure 5-3 for a full connectiondiagram for the solar thermal system,including wiring of the hot waterstorage cylinder thermostats and hightemperature motorised (or solenoid)valve on the solar thermal input to thecylinder. Figure 5-4 shows the cablingarrangement for this system.

Figure 5-3: Solar thermal system wiring diagram

Collectorsensor230V 3A

fused supply

Cylinderbottomsensor

Solar pump

2-portzone valve

ControlHigh limit

Dual thermostat(Solar coil)

Grant GSD1 Mk2 Controller

NEL

N E L

LNE

Inst

alla

tio

n

13

Figure 5-4: Cabling diagram for system controls

5.3 Fitting the controllerWhen the electrical connections to thewiring base are all completed, re-fit thecontroller. Carefully locate the controllerinto the wiring base and, applying aneven force on each end of thecontroller, push fully into place until thetwo grips (one at either side of thecontroller) are correctly located.

If there is any resistance do not forcethe controller into the wiring base, butremove and check for any obstructions(e.g. wires, etc.) before attempting tore-fit. Ensure that the connecting pinson the back of the controller are allstraight so that they can be located intothe corresponding holes in the terminalblocks in the wiring base.

Collectorsensor230V 3A

fused supply

Cylinderbottomsensor

Solar pump 2-portzone valve

ControlHigh limit

Dual thermostat(Solar coil)

Electricaljunction box

4 – Core (3+Earth) 3 – Core (2+Earth)

3 – Core (2+Earth)

Grant GSD1 Mk2 Controller

NEL N E L

LNE

14

Sys

tem

6 System

Refer to Section 5 – Figures 5-3and 5-4 for system electricalwiring diagram

! NOTE

IMPORTANT

Cylinder thermostat andtemperature sensor positionsmay differ from those showndepending on the make and typeof cylinder used.

6.2 System typeIn order for the controller to function asdescribed above, the controller issupplied with the ‘system’ parameter(P17) factory set to 1. This parametermust be checked during commissioningto ensure it is correct. It should onlybe set to 1 unless advised to do so bythe Grant Technical Department.

Figure 6-1: Schematic diagram of Grant solar thermal system

Grant GSD1controller

Solarcollector

High temperature 2-port orsolenoid valve (not supplied)

Solar circulating pump

Electricaljunction boxCylinder temperature

sensor (E2)

Collectortemperaturesensor (E1)

Dual thermostat

Solar pump station

6.1 System operationThe Grant GSD1 solar controllerautomatically operates the systembased on the following:

• The temperature difference betweenthe collector (E1) and the solar partof the hot water storage cylinder (E2)

• The temperature of the collector (E1)

• The temperature of the solar part ofthe hot water storage cylinder (E2)

Refer to Section 4 for details of theoperating functions.

Co

mm

issi

oni

ng/

Pro

gra

mm

ing

15

The controller remains active in theselected operating mode even whenin the programming mode!

! NOTE

7 Commissioning/Programming 7.1 Programming modeThe programming mode is accessed bypressing and holding the push buttonfor at least 2 seconds.

By pressing the push button again andholding for at least 2 seconds, thecontroller exits the programming modeand returns to the previous mode – Off,Auto or Service.

If the controller is left in theprogramming mode for greater than30 minutes it will automatically exit andreturn to the previous mode – Off,Auto or Service.

To adjust the controller parameters use the following procedure

7.2 Setting the controllerAfter having installed the controller andmade all electrical connections, switchon electrical supply.

The software status of the controllerappears on the LCD display for 2seconds, followed by the solarcirculating pump type detected by thecontroller (Parameter P92).

The factory settings for the first start-upare as follows:System 1 (Parameter 17)Operating mode Off (see section 3.1)

STEP 1 Press push button and holdfor at least 2 seconds to enterProgramming mode.

STEP 2 Operate Adjustment dial toselect parameter to be adjusted.Refer to Section 7.4 for table ofall the controller parameters.

STEP 3 Press push button briefly toenter parameter adjustmentmode – line will be flashing.

STEP 4 Adjust value of parameteras required using theAdjustment dial.

STEP 5 Press push button brieflyto set Parameter value

STEP 6 Repeat steps 2 to 5 for allother parameters to beadjusted – refer to Section 7.3

STEP 7 Press and hold push buttonfor at least 2 seconds to exitprogramming mode

STEP 8 Press push button briefly toset operating mode to Autofor solar controller to operate

(t>2 s)

(t>2 s)

16

Co

mm

issi

oni

ng/

Pro

gra

mm

ing

7 Commissioning/Programming 7.3 Parameters settingsALL the following parameters must beadjusted and set by the installer prior tooperating the system for the first time.Refer to Section 7.4 for a Tableshowing all parameter settings of thecontroller.

Step Parameter Setting required

1 P01 Set to the correct time of the day

2 P02 Set to correct day of the week

3 P15 Enter password to access further parameters

4 P62 Set to 55ºC (before setting parameter P60) – this must be set 5ºC lowerthan parameter P60

5 P60 Set to 60ºC

6 P80 Set to 0 (before setting parameter P82)

7 P82 Set value of system flowrate (in litres/sec)

8 P90 Set to 0

9 P92 Set to 0

10 P93 Set to 0

Co

mm

issi

oni

ng/

Pro

gra

mm

ing

17

7.4 Solar controller parameters

P Function Setting Range Units Factory Installer Range Settings Settings

00 Resets the factory settings 0/1 0 As required

01 Time 0.00 – 24.00 10 To suit

02 Day of the week MO – SU MO To suit

03 Daily output (reset =1) 0/1 0 As required

04 Total output (reset = 1) 0/1 0 As required

05 Pump kick: switch-on time 0.00 – 24.00 7.00

06 Pump kick: switch-off time 0.00 – 24.00 22.00

15 Password entry: access to the following parameters 0000 – 9999 0000

16 Password (entry/change) 0000 – 9999 0000 As required

17 System 1 – 5 1

20 Difference for output A1 “ON” 1 – 30 K 6

21 Difference for output A1 “OFF” 0 – 29 K 3

30 Minimum collector switch-on temperature -20 – +90 ºC 20

31 Minimum collector switch-off temperature -21 – +89 ºC 15

32 Collector cooling function: switch-on temperature 80 – 180 ºC 115

33 Collector cooling function: switch-off temperature 75 – 175 ºC 110

34 Maximum collector switch-off temperature 80 – 180 ºC 120

35 Maximum collector switch-on temperature 70 – 170 ºC 105

60 Maximum storage cylinder charging temperature 5 – 95 ºC 85 60

61 Collector cooling function: Max. storage cylinder temperature 10 – 95 ºC 90

62 Maximum storage cylinder switch-on temperature 4 – 94 ºC 80 55

75 Pump kick: break 10 – 60 min 30

76 Pump kick: OFF (0)/kick interval 0/2 – 59 s 0

77 Pump kick: measuring time for 0.5K increase 1 – 10 min 1

80 Calorimetry (ON = 1) 0/1 1 0

82 Volume flow for heat quantity calculation 0 – 100 l/min 0 To suit

84 Glycol concentration 0 – 70 % 40

85 Glycol type (Propylene = 0, Ethylene = 1) 0/1 0

90 Error messages Er62/Er63 (display inactive = 0/active = 1) 0/1 1 0

92 Pump type A1 0/1/2 0

93 Operating mode volume flow control (manual = 0/auto = 1) 0/1 1 0

94 Number of revolutions, nominal value (MANUAL) (5) 30 – 100 % 100

IMPORTANT

ALL highlighted parameters MUST be checked andset as shown above during commissioning.Refer to Section 7.3.

All parameters from Parameter16 onwards can only be adjustedafter entering the password –at Parameter 15.

! NOTE

18

Faul

t Fi

ndin

g

8 Fault Finding8.1 Error messages

8.2 Checking for faultsTemperature sensorCheck the connections of the sensor atthe controller (and at any junctionboxes).Check the condition of the sensor andsensor lead.Check sensor is correctly located incollector or storage cylinder (asappropriate).Check sensors are correct – i.e.collector sensor is in collector, cylindersensor is in cylinder.Check the resistance of the sensoragainst the temperature (refer toSection 2.2).

Danger: Isolate 230V electricalsupply BEFORE removing controllerunit from wiring base to checksensor connections

No FlowCheck flow meter in pump station toconfirm flow rate. Check solar circulating pump isrunning.Check all valves on the solar primarysystem are fully open.

Flow too lowCheck flow meter in pump station toconfirm flow rate. Check all valves on the solar primarysystem are fully open.Select a higher solar pump speed.

No energy collection displayedCheck Parameters 80, 82, 84, 85, 92and 93 are all correctly set.

Unable to adjust Parameter settingsfrom P16 onwardsEnter either 4-digit default password(0000) or your amended password atParameter 15.

Message Cause Explanation

Er 71 E1 delivers undefined values The output (A1) to the solar pump is switched off.The error message cannot be acknowledged, the display only shuts off afterthe error has been eliminated. In order to do this, interrupt the power supply

Er 79 E2 delivers undefined values to the controller for approx. 20 seconds.Check the ‘Temperature sensor’ – see Section 8.2Set to correct day of the week

Er 64 No Circulation Pump failed System airlockedCheck - rectify (see below)

Er 81 EEPROM All outputs are switched off.Send the controller to manufacturer with a list of the system parametersthat were set

Faul

t Fi

ndin

g

19

GRANT ENGINEERING (UK) LTDHopton House, Hopton Industrial Estate, Devizes, Wiltshire. SN10 2EU

Telephone: 01380 736920 Fax: 01380 736991Email: info@grantuk.com Website: www.grantuk.com