Honeywell 4043B ('Mains Off' open MV) - replacement head where?

[Rob G]

I have the MV in my system that controls the heating to the HW tank. A Dunsley Neutraliser blends the heat from the oil boiler and the wood stove back boiler and the MV stops the flow to the tank when it's hot enough. The valve has failed open and the HW is far too hot. The MV is a Honeywell 4043B - such that it is open on mains failure.

Investigation shows the head has failed - the quadrant gear is jumping, so a replacement motor is a no-go. I cannot find anyone stocking the head for this MV - can someone help please.
Cheers, Rob

 

[gas112]

Honeywell Home 40003916-001 2 Port V4043H Replacement Powerhead - Screwfix

Order online at Screwfix.com. Designed for field replacement of heads for 2-port motorised valves. This positive head can be used to replace the removable valve heads without any system drainage. Straightforward installation using only 2 screws and 2 locating pegs to connect the heads to the...

www.screwfix.com

 

[oldbutnotdead]

I have the MV in my system that controls the heating to the HW tank. A Dunsley Neutraliser blends the heat from the oil boiler and the wood stove back boiler and the MV stops the flow to the tank when it's hot enough. The valve has failed open and the HW is far too hot. The MV is a Honeywell 4043B - such that it is open on mains failure.

Investigation shows the head has failed - the quadrant gear is jumping, so a replacement motor is a no-go. I cannot find anyone stocking the head for this MV - can someone help please.
Cheers, Rob

Try that one linked above- Screwfix and Toolstation take returns. I don't know whether the B uses a different gearbox to the H- you might get lucky . If you don't then it's new valve and swap the mech over.
As a matter of curiousity, where does the spare heat from the neutraliser go when that valve is closed? Heat dump rad or somewhere else?

 

[DP]

What is the quadrant gear. Is the head on the valve or off It. If off it, the gears train is not healed in place so will keep jumping to home position

 

[stem]

Honeywell Home 40003916-001 2 Port V4043H Replacement Powerhead - Screwfix

Order online at Screwfix.com. Designed for field replacement of heads for 2-port motorised valves. This positive head can be used to replace the removable valve heads without any system drainage. Straightforward installation using only 2 screws and 2 locating pegs to connect the heads to the...

www.screwfix.com

That's a V4043H which is a normally closed powerhead. The OP wants a V4043B that is normally open. The V4043B can be identified because as it is normally open, it doesn't need a manual opening lever (hence the vacant slot) or have an internal microswitch, so only has a 3 wire connection.

And if anyone knows where a V4043B replacement powerhead is available, I would like to know too.

 

[ianmcd]

That's a V4043H which is a normally closed powerhead. The OP wants a V4043B that is normally open. The V4043B can be identified because as it is normally open, it doesn't need a manual opening lever (hence the vacant slot) or have an internal microswitch, so only has a 3 wire connection.

View attachment 292691

And if anyone knows where a V4043B replacement powerhead is available, I would like to know too.

BES.co.uk | Next Day Delivery On 15,000 + Plumbing Supplies

Order Honeywell motorised valves and other heating valves online at BES.co.uk. Low Prices, Free Next Day Delivery Available, 15k Plus Products in stock. P/N: 14500

www.bes.co.uk

 

[gas112]

That's a V4043H which is a normally closed powerhead. The OP wants a V4043B that is normally open. The V4043B can be identified because as it is normally open, it doesn't need a manual opening lever (hence the vacant slot) or have an internal microswitch, so only has a 3 wire connection.

View attachment 292691

And if anyone knows where a V4043B replacement powerhead is available, I would like to know too.

cheers stem missed the B bit

 

[Rob G]

Thanks IanMCD - just along the road from you. I should have probably said that it was NOT the 4043H !! I suspect that many didn't know the difference.
Unfortunately it is looking ominously like the head is not available for replacement, and I will have to buy the whole valve and then take the head off. I'll give BES a phone in the morning.
OldButNotDead - the valve is closed when CH is called for. If the mains goes and the wood boiler is hot then the tank is the dump.
Many thanks to all for your inputs.
Rob

 

[stem]

BES.co.uk | Next Day Delivery On 15,000 + Plumbing Supplies

Order Honeywell motorised valves and other heating valves online at BES.co.uk. Low Prices, Free Next Day Delivery Available, 15k Plus Products in stock. P/N: 14500

www.bes.co.uk

The whole valve I can find OK. It's just the powerhead that seems to be unavailable..

 

[ianmcd]

The whole valve I can find OK. It's just the powerhead that seems to be unavailable..

Can you not just change the synchron motors rather than the actuator ?

 

[oldbutnotdead]

Apparently the quadrant gear is FUBAR.

 

[fixitflav]

Apparently the quadrant gear is FUBAR.

Isn't the quadrant gear part of the synchron motor, not the valve body?

 

[oldbutnotdead]

Isn't the quadrant gear part of the synchron motor, not the valve body?

Not sure about the B, I'm sure you can get bare motor and motor with gearbox for the H.

 

[fixitflav]

Not sure about the B, I'm sure you can get bare motor and motor with gearbox for the H.

OK, just wondered