At Heatmiser, we are the manufacturers of the thermostats and control centres which do not require any regular servicing.
We would therefore suggest contacting the supplier of your heating system who will be able to advise of any required servicing and partners they have to carry out this work.
Heatmiser do the controls, not the plumbing side, therefore as long as the heating is being turned on and off by our controls, anything on the plumbing side is usually done by a local heating engineer or plumber.