Danfoss Hs3 valve live lead

[AndyDanfoss]

hi
I have recently converted from a warmflow conventional 19yr old oil boiler to an Ideal gas boiler leaving in place the immersion tank.

It has a danfoss 3 way valve feeding A and B and works off a danfoss timer programmer. All was fine until the last few days and the requirement for radiators ie A port. The heating was used at night however no hot water as per timer in the morning. Further examination of the danfoss reveals that the side lever was loose and had no tension therefore unable to move the valve to port B.

When I fully power down the system I can hear the motorised spring in the valve resetting back to hot water port B default and it works!...until the next time CH or Port A is used.

I'm confused, the difference between the oil and gas system is that the gas needs a permanent live, I'm thinking that the Danfoss valve needs to power down also and therefore reset each time??

Any thoughts would be appreciated

 

[DP]

The MV is doing what you ask of it hence the lever is slack. With no power to MV, the lever would be slack half way up the slot.

 

[AndyDanfoss]

This happens when the central heating is on and Port A is serviced however it does not springback to the top when its completed the heating period.
In the morning the hot water cycle becomes a radiator heating session as the valve does not move from the slack lever in the bottom or near bottom of the side of the valve UNLESS which i have discovered the system is powered down. Then the spring kicks in and the lever goes up to the top.
I should of said that I have changed the danfoss valve so the valve is fine

 

[Johnmdc]

The valve will stay in the heating position until there is a call for hot water or the power is cut.
So assuming it is wired right then the problem is either your timer or the cylinder thermostat.
Depending on what type of cylinder stat you have some have got on over- heat cut out that can be reset.
Post a picture of it.

 

[picasso]

Check the hot water off wires are connected, there should one from the programmer and another from the cylinder stat.

 

[oilhead]

As Picasso says. If the live feed (grey) is fed from the switched live from the programmer, then this happens. There is no difference in Y plan wiring for gas and oil boilers.

 

[AndyDanfoss]

Please see attached photo, the wires entering at the bottom indicated by the hand is from the timer/programmer the one to the left of it is from the danfoss 3way valve.
Anything sticking out that wrong?
Thanks for the help so far guys
Hot water came on this morning ok as the central heating wasn't used last night. Once the central heating is introduced the spring lever on the danfoss valve is then slack and runs central heating only until manually powered down.

 

[picasso]

to make sense of the wiring you would need to trace and label the cables, only thing I can see is you have an extra cable in 3 / 9.

 

[AndyDanfoss]

Stuck at work at the moment, I'll try later thanks