Antman's Web Pages

DIY installation support for Navitron Solar Heating Systems

Navitron solar panel installed
OK - Do you need to know how to wire the solar components into an existing central heating system?
Are you installing a complete new system with solar and want to know how to wire it all up? If so, read on!

Updated  18/10/12
I have updated and improved the original wiring schematics file into multiple files.
The new generic System Schematic files offer several improvements over the original versions in that they:
a) Support the boiler 'Pump Over-Run' capability and are suitable for all boilers using a common-neutral connection to boiler and pump.
b) Utilise the industry standard terminal box numbers for the Y-Plan and S-Plan Schemes - an oversight on the original.
*** Please note previous Y-Plan file incorrectly showed V4073 white wire connected to 4PCO relay NO2. It should go to NO3. Thanks to chilled for pointing this out.
c) Offer multiple tab options to use a bypass radiator permanently connected to the boiler pump circuit as the Heat Dump or to dump into the full central heating radiator circuit.
d) Add alternative tabs for the original Resol BS/3 and BS/4 and the Navitron TDC2 and TDC3 solar controllers.
e) All use the same 4-pole changeover relay with standardised connections across all Wiring Plans. This makes it easier for installers as you only need one type of relay.
    Some schematics have a spare unused pole - this may be used for future updates....

Download System wiring schemes S-Plan.xls (Microsoft Excel approx. 98KB) for the NEW S-Plan file.

Download System wiring schemes Y-Plan.xls (Microsoft Excel approx. 92KB) for the NEW Y-Plan file.

Download System wiring schemes S-PlanPlus.xls (Microsoft Excel approx. 133KB) for the NEW S-Plan+ file.
PLEASE NOTE: Each file contains multiple Tabs, one for each schematic. You cannot see all the available options unless you scroll through the tabs using the arrows in the bottom left of the Excel screen!
These variants should work as they are derived from the original files. If anyone finds any errors please PM me and I will correct and update!

Condensing boiler compatibility
There has always been concern over the complex control electronics of modern condensing boilers making it difficult or indeed impossible to utlise the domestic central heating radiator circuit as a Heat Dump if required.
The Alpha CDR and Remeha Avanta ov ranges have both been used by me with the common-neutral schematics.

Download System wiring schemes S-Plan Alpha CDR.xls (Microsoft Excel approx. 84KB) for the S-Plan Alpha CDR boiler system file.
This can also be used on the Avanta - just update the boiler terminal connections accordingly.

I intend to update these files to a set of Universal Schematics ASAP utilising the spare relay pole to isolate the pump neutral.

The process of installing and integrating the Navitron Solar System into my own existing S-Plan Plus central heating system is described in my DIY Solar Heating Review (Adobe .pdf format 0.96MB - updated June 2008)

The V4073 page gives details of a simple modification to greatly improve reliability of the Honeywell V4073A synchron motor in Y-Plan systems and can also be applied to V4043H 2-port valves.

Installation manuals for the Resol range of Solar Controllers can be downloaded from the Resol Website 
(Note: Select Service and then Documents from the menu tabs for the full range)

Visit the Navitron logo website at  for all your Renewable Energy requirements.

You are welcome to PM me (Antman) via the Navitron Forum . However please post general questions in the relevant section of the Forum so that all members can benefit from the responses.

Photo images of my own installation

Lower frame mounting Insulated end box End box S4 sensor mounting Tundish overflow
Lower frame mounting Insulated end boxes providing additional protection - note these are not provided as part of the kit S4 sensor mounting Tundish overflow

Cylinder pipework Boiler and solar pipework Upper pipework
Domestic water pipework with TMVs Complete solar, boiler and CH pipework Pumps and DHW boiler pipework - see Review text for explanation of DPV on boiler coil

Lower pipework Air vent Hozelock
Lower pipework - two independent radiator zones. Two 10mm pipes in right foreground feed the bathroom radiator direct from boiler circuit, which now doubles as the heat dump load when excess solar energy is generated. Built-up manual air trap/vent (and PRV) Hozelock plant spray for adding anti-freeze - uses additional 3/8" bsp to 15mm compression adaptor

Terminal box System controls
Relay and wiring terminal connection box Two dual zone programmers for system control
Pre-lagged pipework Original pipework Original heating
I found this earlier shot which shows the solar and boiler pipework before lagging. At this stage the 'Slave' solar relay is not installed since the solar system has not yet been finally filled. But it does allow the boiler to run and the solar controller to be programmed and sensors checked. And finally - how much simpler it all was before solar and full Part-L compliance...

Copyright notice and the Legal bits:

Regrettably it is necessary to emphasise the legal terms and conditions for use of the documents on these web pages, since a minority seem to be taking liberties with this and Navitron documentation.

All images and files are copyright of the author A.J.Cooper, March 2006 to current date.
Images and files may be reproduced for personal use and are provided for support of Navitron Ltd solar system installations and Navitron customers only.
Strictly no editing, reproduction or publishing for commercial use except by Navitron Ltd, with the following exceptions:
a) Use of the files in their entirety to assist and promote the sale and installation of Navitron Ltd solar systems by a Navitron installer; all references to Navitron and the author must be retained in all cases.
b) A copy of customised versions of any wiring file template used in an installation may be left with the customer by a Navitron installer to enable compliance with the documentation requirement of the current Wiring Regulations.
The author retains copyright of the master files.
The modification of any image or file to imply endorsement of any company or product other than that of Navitron Ltd is strictly prohibited.
Information is provided for assistance only. Strictly no liability is accepted by the author or by Navitron Ltd for errors or omissions. It is the user's responsibility to check that information provided, and suitability for any installation based on it, conforms to current Planning, Building and IEE Wiring Regulations.


Last updated 18/12/14