Mr Combi has produced two training DVDs to help you get the most out of your multimeter. They are designed to teach you both the basics and more in depth procedures. You can play them over and over, in the comfort of your home, to ensure you learn as much as possible from Mr Combi’s wealth of knowledge and experience.

We have also created two books which will help you find the information you need when working at a customer’s house.

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Central Heating Wiring & Controls Book

For many years electricians and heating engineers have commented that wiring heating controls is a difficult subject to learn. They want to be able to wire up and test these circuits with confidence but the existing diagrams are not always easy to follow.

Following the example of the London Tube Map, we’ve developed a fantastic new set of coloured wiring diagrams for Danfoss and Honeywell controls.

In our Central Heating Wiring & Controls book you’ll find a vast array of information and diagrams, including:

  • Four part Electrical Safety Tests
  • Danfoss
  • Honeywell
  • Drayton – NEST – Hive
  • Frost Protection
  • Schematics
  • Fault Finding Charts
  • SMART Controls
  • Programmer wiring
  • Checking components
  • Over 100 pages of technical info
  • Handy A5 size and wire bound
  • Full colour diagrams
  • High quality paper

Our very popular book is an excellent reference for you to use on central heating wiring.

The book is available in A5 size.

£25.00 each including P&P (no VAT, UK Post code only)

Central Heating Fault Finding*

Our latest book is jam packed with fault finding methods.

Do you ever get to a customer’s house, the boiler is dead, blows fuses, cuts out, noisy, poor circulation and no servicing manual? With our book you won’t need it, you should find the problem.

  • Factory flow charts, pressure loss, fault isolation, easy diagnostics
  • Faults with expansion vessels, pumps, by-pass all are explained
  • Full sized A5
  • Wire bound

*Refunds will not be made because of errors or omissions, content is supplied by manufactures in good faith. Please email us of errors / omissions.

Central Heating Fault Finding Book

The book is available in A5 size.

£25.00 each including P&P (no VAT, UK Post code only)

CO/CO2 Chart

The printout will have 4 lines: 02, CO, CO2, Ratio. The CO2 is important because it’s shows HOW good or bad the boiler is performing.

First read the M.I. to see what it should be. White good, Orange call the manufacture for guidance, RED shut down ID. Printed on Flexi-plastic with easy to follow instructions, show the customer how their boiler is performing.

£4.00 each including P&P (no VAT)