Issue
Drayton Theta Autotherm Controller requires replacement.
Environment
Stand alone discreet Drayton Theta Autotherm Controller applications.
Cause
Obsolescence of Drayton Theta Autotherm Controller.
Resolution
A. Controller - Overview
The Drayton Theta Autotherm Controller was manufactured primarily for use in domestic heating applications.
The Drayton Theta Autotherm Controller combined the following functions in a single stand alone discreet Controller :-
Heating System Compensator
HWS Programmer.
There is no simple like for like replacement currently available but the two functions may be replicated as shown below.
B. Controller - Replacement
1. Suggested replacements for Autotherm Heating System Compensator function and associated Sensors :-
Compensator Controller = CSC5252 or CSC5352, details of which may be viewed here.
(The CSC5352 may be programmed to provide automatic Night Set Back)
Outside Air Temperature Sensor = STO600, details of which may be viewed here.
Clamp-On Temperature Sensor = STC600, details of which may be viewed here.
(Use of a Clamp-On Temperature Sensor eliminates the need for any pipework modifications)
N.B.
The existing Drayton Theta Autotherm Heating System Actuator and Valve Body may be retained should these both be in working order.
Alternatively, suggested replacements for the Drayton Theta Autotherm Heating System Actuator and Valve Body are :-
Actuator = MD10B-24 or MD10B-230, details of which may be viewed here.
Linkage Kit = LMD/AR-MB (914-1071-000), details of which may be viewed here.
Valve Body = MB (select size from ½” to 2” size), details of which may be viewed here.
2. Suggested replacement for Drayton Theta Autotherm HWS (Hot Water Service) Programmer function :-
We do not offer an independent Programmer but such a product should be available from the Distributor supplying the S-E Satchwell CSC Compensator Controller and associated Temperature Sensors.
N.B.
Any existing Relays that are currently installed may also be retained, in order to complete the replication of the Drayton Theta Autotherm control scheme.
