Honeywell V4043H1056 22mm 2-port zone valves have five wires: green/yellow is Earth, blue is Neutral, brown is Live (or Line) to the motor, grey and orange are connected to the end switch and form part of a separate circuit.

V4043H1080 is a 2 port, 1” BSP Female threaded, 6-wire, normally-closed zone valve with an auxiliary end switch Honeywell V4044C1288 22mm 3-port diverter valve. This valve is not a mid-position valve. It opens either Port A or Port B (usually heating and hot water). Apart from the few moments when it is switching between ports, Port A and Port B are not open together. Note that it is a 3-wire valve, not a 5-wire valve The Honeywell mid-position motorised valve has three ports in a T configuration. Water enters via port AB. Water leaves by either port A or port B or by both at the same time. Port A is normally connected to the radiator circuit and Port B to the cylinder coil (to heat hot water). The circulating pump is usually connected to feed water from the boiler into port AB.When a V4073A mid-position valve is set up in a Y-Plan configuration and Hot Water is called for, power to the boiler is provided directly from the cylinder thermostat. The valve is not energised. Honeywell 2-port motorised zone valves (V4043H) are electrically quite simple. The powerhead contains the motor, which is used to drive the valve open, and an auxiliary switch or end switch. Honeywell 22mm zone valve operation (V4043H1056) If the powerhead was removed from the valve to make it easier to change the motor, it must now be re-attached to the valve. The power head cover can then be refitted and secured with the single screw. Make sure it sits squarely on the powerhead, with no wires pushing out from the sides. In larger properties, 28mm valves may be used (the 5-wire 3-port V4073A1088 and the 6-wire 2-port V4043H1106). The 28mm V4043H1106 2-port zone valve has a6 th wire, coloured white. This white wire might not be used. In that case it should be made safe electrically.

There are lots of poor quality synchronous motors out there. If the motor cap says “Synchronous” rather than “SYNCHRON ®” it may cost less than half but you’ll probably be changing it again before long! Where possible a photo of the V4073 Sychronous Motor detail is included in the listing for identification purposes onlyYou should be able to feel a bit of spring resistance, right at the far end (Man Open end) of the slot. The Honeywell motorised valve faults detailed above are likely to apply to most domestic Honeywell valves. Honeywell make a large range of motorised valves used in domestic central heating systems. The most common by far are the 22mm 3-port, 5-wire, mid-position valve and the 22mm 2-port, 5-wire, zone valve. These 22mm valves (3-port V4073A1039 and 2-port V4043H1056) are used in smaller and medium sized properties. im not good enough with this stuff to do the multimeter thing and even if i figured out what the problem was, id definitely need to get a plumber in to fix it so might as well call him now! Much of what we describe also applies to ACL Drayton motorised valves like the Drayton 2-port ZA5/679-2 22mm zone valve and the Drayton 3-port MA1/679 22mm mid-position valve. Iflo motorised valves and British Gas motorised valves have similar faults. It may also apply to the Tower VAL222MV motorised valve, the Siemens CZV222 motorised valve and the Flomasta 27900SX motorised valve.