vokera linea 24 motorized valve leaking

[Gordon133]

hi I have a Vokera Linea 24 Combi Boiler that has just starting leaking from what looks like the motorized valve. It has also developed an intermittent problem with the hot water whereby when you turn the hot tap on it heats up and then cools down and then heats up and then cools down and so you do not get constant hot water (not great in the shower!!).

Is the leaking water easy to fix?

Are the problems related?

Your help would be greatly appreciated.

Many thanks

 

[twgas]

Your problems are probably related, not sure what diverter you've got but the dirt in the system has more than likely caused the leak and blocked the plate h/ex.

 

[1983]

Hi, could water be getting into the diverted motor, this can cause it to motor on and off constantly which would put all your hot water power to the radiators. Worth a look. With the boiler cold turn on hot water and you should hear the motor move once only, if it keeps making noises it's likely got water inside. Also check the heating flow pipe to see if that gets hot when the water is on.

 

[DP]

1983. Better to stick with facts

OP dirty system and lack of proper service is the problem

 

[1983]

1983. Better to stick with facts

OP dirty system and lack of proper service is the problem

You never had a vokera divert or diong this? Fact is water leaking, perhaps at spindal, perhaps into the motor, just like you I'm not standing in front of boiler, a suggestion was all it was and something to rule out.
Perhaps the op would be kind enough to post back when it's fixed?

 

[ianmcd]

The early lineas did suffer from water leaking through the front end seal getting into the actuator motor but in my experience caused them to fail totally and not intermittently as the OP describes, later ones had a hole drilled in the front end plate which allowed any leaking water to drip out and protect the motor, intermittent HW on a Linea can have a few causes but in my experience unlikely to be the divertor actuator

 

[DP]

1983, what the water causing the motor to drive? Never. Had diverter passing to rads during HW demand but never had a diverter drive round in presence of water.

All I know is, water in the diver motor will blow a fuse on accound of close proximity of L and N. It is remove switching that allows the motor to drive to demand that is applied to boiler. If water can act as a changeover switch, well then that is new to me.

 

[McCombi]

Sounds like plate heat exchanger is restricted and boiler is cutting out and on due to it overheating then firing up again and going through that cycle.

You can test this as follows:

When hw is run at tap the display shows the temperature of the water, and when it isn't running it shows the central heating water temperature.

Run your hw tap and whilst looking through the sight glass at the burner, when the burner switches off, quickly turn the water isolating valve (black handle at furthest right hand side pipe under boiler) 90 degrees anti clockwise.
This isolates the water to the boiler and the display will then show the central heating temp. If its around 90 degrees then its shutting off due to it overheating and you will need to replace the plate heat exchanger.

It can also be a faulty non return valve but I've personally never had to replace one, worked n these daily in my old patch.

Remember to turn the valve back upright to get hot water, careful not to turn it fully down as this may top up your boiler pressure.

If its not showing a high heating temperature when you do the test, its something else which is common but you will require an rgi to fix it.

 

[1983]

now i've got to find the answer to this one
Used to look after a couple of estates with lineas and linea max and have had the problem several times, open the motor, dry it with a hair dryer and it works fine.
The motor housing and most of the assembly is plastic and has no earth. If water bridges between the two live pins inside and not the neutral it wont blow or burn out anything, maybe I'm wrong but it would just conduct electricity between the two wires. question is why would the motor then just cycle back and forward. Power changing between coils in the motor or something happening back at the pcb?
edited to say that all the ones I seen had the connector to the motor at the bottom, turning the motor 90deg seemed to help.

 

[Gordon133]

Many thanks for joining my vokera topic and great advice. Boiler is off at the moment ( thanks to the weather). The temperature of the hw was fine when the water flow was very small. Any increase of the flow caused cold water than hot again and cold again. It looked like the boiler was to weak to cope with more water (linea 24), 3 bed house but it must be something else. I am not specialist. Also when ch is "on" the pressure going up from 1.2 to 3 bars within 5 minutes. I got advice that leak may be on the front seal or "o" ring of the divert. valve. It may give some more details, thanks a lot for help!

 

[DP]

Gordon, I will repeat what I said earlier- dirty system ( hence hot and cold water- nothing to do with boiler power as it is designed to supply specific quantity of water) and boiler needs to be serviced. If boiler had been serviced as per the manual, pressure would be stable

 

[Agile]

Actually 1983 is not totally wrong about the motor.

They rely on the contacts opening when the motor reaches either of the two resting positions and ater inside can bridge those contacts and cause the motor to continue to run.

They should always be orientated with the contacts upwards!

Tony

 

[DP]

They should always be orientated with the contacts upwards!

Tony this I would like to see you do on a Linea. For a man I treat with respect you do come away with some strange ideas

 

[Agile]

That is how they should be fitted to get the maximum reliability.

If a manufacturer makes that impossible on a particular model then its a bad design!

But equally boilers should be fitted to clean systems so that the pin seals are not damaged!

Tony

 

[Gordon133]

I got the quote from corgi today. In his opinion problem with hw is the faulty heat exchanger (may need cleaning only)? (brassedoff was right! I also did the test recommended by him with isolation valve when turned off temp. show 92 deg. According to the high pressure plumber said need change expansion vessel, and last thing to do leak from the motorized valve that from divert. valve. I got the quote for 485 pounds (parts and labour) to change all that parts. What you think about this, it seems to be quite expensive. Is any point to do that job, I can get new boiler for that money plus fitting charge. I would like you know your opinion. Could you recommended any combi for 3 bed semi. Many thanks!