Have a solar system, quite old and the switch between the solar/ domestic is manual and uses a Drayton Actuator model, TA/M2, when I switch it it normally reaches the limit and turns off, it has just started making a clonking noise when it reaches its limit, does this mean the actuator is worn, if so can i replace it myself and is it a simple job or can it be repaired as a search on google shows to buy one is very expensive. - thanks
Further to that and just a thought, if it has to be replaced can i fit an automated switch rather than a manual?