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INSTALLATION AND USER INSTRUCTIONS - RAM1T

Wiring

1. Are you replacing an existing cylinder/pipe

thermostat? 

Then follow the information in

Section (B).

2. Is this a new installation? 

Then follow the

information in Section (C).

The connections to this thermostat are as shown
in the wiring diagram but for clarity note the
following:

Terminal No. 1 is the Common and receives a
signal either directly from the fuse spur or from
your HW programmer or timeswitch circuit.

Terminal No. 2 is the Normally Closed/Break on
rise (or call/on need heat) output and should be
connected to the switched live of your central
heating boiler, or the switched live of a
motorised two port zone valve.

Terminal No. 3 is the Normally Open/Make on
rise (or satisfied/off no heat) required and would
normally be connected to the offside of valves
that need power to close, or to position them;
(zone valves and 3 port mid position valves).

There is also an Earth terminal on the brass plate
and this must be connected to a proper earth
point, to ensure continuity.

Section (B) — Replacing an existing
cylinder/pipe thermostat

Prior to carrying out any work, you must isolate
(turn off) the electrical supply to the thermostat
either at the fused spur or the mains. It is
recommended that this circuit has a maximum
of a 3 amp fuse and if not, replace with same.
Make a note of all connections, eg. Honeywell:
RED is connected to Terminal No. C; YELLOW to
Terminal No. 1; BLACK to Terminal No. 2 and so
on.
Now refer to the interchange table below and
note the new terminal numbers; eg. Landis &
Staefa RAM1T: RED will go to Terminal No. 1;

Yellow to Terminal No. 2; BLACK to Terminal No.
3. Remove the old unit and reconnect using the
new terminals plus ensuring the RAM1T is
correctly earthed.

NOTE: The colours shown above are examples
only and may have not been used in every
installation and it is advised you primarily rely
on the terminal numbers shown in the
interchange guide.

Section (C) — New installation
(or adding to an existing system)

If you are installing the thermostat to an existing
system you will need to identify the style of
system and control you are looking for and then
refer to the relevant information. Prior to carrying
out any work, you must isolate (turn off) the
electrical supply to the whole system.
Refer to the terminal numbers and note:

1.

On most current zone valve systems you will
only have to use Terminal No. 1 (common) and
Terminal No. 2 (call/on), ie. the supply from your
timer will go to Terminal No. 1 and the load (ie
pump, valve, live, etc.) to Terminal No. 2.

2.

On all current 3 port mid position systems all
three terminals will be used. Terminal No. 1 
receives the LIVE; Terminal No. 2 connects to
the WHITE wire and Terminal No. 3 connects to
the GREY.

3.

If you are adding this unit to an existing older
type gravity HW system please note that
without a motorised valve with changeover
contacts the benefits will be minimal (wiring
diagrams for these style of systems are
available on application).

If you are still not sure, or having problems, then
phone the Technical Help line on 01952 602048,
open Monday to Friday (except Bank Holidays)
from 9am to 5pm.There is also an answerphone
message system in operation 24 hours a day.

Landis & Staefa

RAM1 (RAM21)

1

2

3

E

Landis & Staefa

RAM2

RED

BLUE

GREY

Drayton

CS1

1

2

3

E

Honeywell

L641A

C

1

2

Sopac

SAY

C

1

2

E

Potterton

PTT1

L

H

C

N

Danfoss

AT

1

2

3

E

Sunvic

1452

3

1

2

E

Sunvic

SA 2451

3

1

2

E

ACL

HTS3

C

1

2

ACL/Tower

HTS2/CS1

RED

BLK

YEL

Randall

CN4

1

2

3

E

Cylinder Thermostat Interchange Guide                            Terminal Numbering

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