V4043H1106 is a 2 port, 28mm compression, 6-wire, normally-closed zone valve with an auxiliary end switch The V4043B valves are uncommon and likely to be found in solid fuel systems. These valves fail-safe in the open position in the event of a power failure or valve motor failure. However, if you need to replace the motor it may be easier to remove the powerhead so you can work on it in the open. Remember, on early Honeywell motorised valves (pre-1985) you can’t remove the powerhead without draining down first! 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.

Honeywell V4073A1039 22mm 3-port mid-position motorised valve showing inlet port AB and outlet ports A and B. This valve can be open to either port A or port B, or to both ports at the same timeMy first thought was that the boiler wasn't firing up because the micro switch(es) to do so were faulty.

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 V4073A 3-port valve has five wires. These are blue, green/yellow, white, grey and orange. Note that the grey and orange wires are used differently from the grey and orange wires of the 2-port valve!

Honeywell 22mm Mid-Position Valve (3 Port) - V4073A1039/U

Seized motorised valve spindle in an old Satchwell Sunvic 2-port motorised valve. The water leakage has caused white oxides to form round the brass spindle, making it too stiff to turn Replacing a failed Synchron motor in a Honeywell motorised valve is quite straightforward, assuming you know how to work with mains electricity safely. Make sure you read the whole process through before starting! If you are able to do so safely, you could try disconnecting and isolating safely the white wire from the motorised valve, and see if the valve moves then when the power is restored. If it doesn't move the problem is with the external wiring, in that the white wire is being energised from somewhere when it shouldn't be. 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. But then I go confused because I was wondering why it was opening the valve in the first place when the controller hasn't asked it to do so.

When I switch on my central heating the boiler does not ignite. All is fine for the hot water though. The commonest fault with Honeywell motorised valves is motor failure. Honeywell valve motor fault? Testing a Synchron valve motor Drive spindle of a Honeywell motorised valve. It is accessed by removing the valve powerhead. Be warned, with Honeywell motorised valves made pre-1985 you have to drain down first to remove the powerhead! I reconnect the power and all the same with motor lever as described in step 3. NB yesterday at this point the valve motor was turning at this point even though controller said off (mind you, hw yesterday was on constant ON but don't believe that would have switched on the motor anyway).It will make it easier when re-fitting it (just remember which end the flex was connected or take a picture on your phone). The powerhead can only fit one way round onto the valve body but if space is tight that might not be obvious. That noise and that bump are diagnostic. They tell us that the valve has moved into the mid-position where both Heating and Hot Water ports are open. If you can make a Honeywell 3-port mid-position valve move into all three of those positions, the valve and controls appear to be wired correctly and the valve appears to be working normally. Left to its own devices with pump on and CH and HW on, nothing seems to be happening in terms of pipes near the valve getting hot 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)

In normal operation, with a heat-only boiler, central heating water is heated in the boiler and then pumped round the system by a circulating pump. Motorised valves are used to split or divert the flow. The heated water can either be sent to the radiators (or underfloor heating) or to the cylinder coil to heat the domestic hot tap water. The cooled circulating water is then returned to the boiler to be heated again. On older style valves pre-1985, which do not have the replaceable head feature, the adaptor plate assembly can be used to upgrade the valves, to allow the replaceable powerhead to be used.”The valve mechanism is physically not allowing water to flow out of either outlet ( but surely this is impossible, one of the outlets HAS to be open as all the valve can do is to close one outlet ?) The Honeywell V4043H1106 28mm 2-port zone valve has 6 wires. Five of these wires are the same as 22mm 2-port valve.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. Is there a way of easily testing whether a pump is functioning properly? I can remove mine, it has isolating valves. As Echo said, the pump is a bit suspicious because Inside a Honeywell V4073A 3-port motorised valve showing the rubber ball which closes one or other port, never both. 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.