Hi there, I have a vokera mynute 20e boiler for rads and dhw, the problem is that even when the timer is on off time, the boiler is still firing up every minute or so. The room thermostat is fully down. Can anyone offer some advice ?
Vokera boiler staying on ?
- Thread starter Wilky423
- Start date
Sponsored Links
sounds like a faulty 2 port valve, have a look for one of these, View media item 24686
If all OFF (HW OFF HTG OFF), must be an external wiring fault, quite possibly faulty moto-valve. However, if its been working OK for a while, would be strange to have suddenly developed a fault in the wiring...
Can you give more background?
When you say Off time - do you mean both HW OFF & CH off...?
If HW still on see picasso's post. If it is a 2-port valve that is, or is it a mid-position (3-ports) valve?
If its a 2-port you could try turning down cylinder stat (if HW ON on programmer) to see if thats stops the boiler clicking in&out.
If its a mid-position valve make sure a couple rads are open closest to valve and see if they warm (if HW ON on programmer).
Really need more help to be able to help more...
Can you give more background?
When you say Off time - do you mean both HW OFF & CH off...?
If HW still on see picasso's post. If it is a 2-port valve that is, or is it a mid-position (3-ports) valve?
If its a 2-port you could try turning down cylinder stat (if HW ON on programmer) to see if thats stops the boiler clicking in&out.
If its a mid-position valve make sure a couple rads are open closest to valve and see if they warm (if HW ON on programmer).
Really need more help to be able to help more...
Thanks for both the above.
I have found two of the above valves one for the dhw and one for the CH.
They have two posns open and auto I'm not really sure which posn it should be in.
The fault has only just occurred system has been okay for 5 years.
When I refer to off I mean system running but the timer setting is is in it's off part of the day
Hope you can help
Steve.
I have found two of the above valves one for the dhw and one for the CH.
They have two posns open and auto I'm not really sure which posn it should be in.
The fault has only just occurred system has been okay for 5 years.
When I refer to off I mean system running but the timer setting is is in it's off part of the day
Hope you can help
Steve.
Sponsored Links
They should be in the auto posn but when HW & CH selected they will be open with no resistance.
Very basic process: Demand for HW or CH will open relevant valve, fire boiler which supplies heat to water in pipes which go through valve and supply demand with heat.
Try pushing the lever on the HW side in particular when the program is off - you should feel resistance as it moves across. If not, there is a fault with the valve.
It actually sounds unlikely as the timer is off yet the boiler still fires... but try and say what u find.
What timer do you have?
And what brand motorized valves are they?
Very basic process: Demand for HW or CH will open relevant valve, fire boiler which supplies heat to water in pipes which go through valve and supply demand with heat.
Try pushing the lever on the HW side in particular when the program is off - you should feel resistance as it moves across. If not, there is a fault with the valve.
It actually sounds unlikely as the timer is off yet the boiler still fires... but try and say what u find.
What timer do you have?
And what brand motorized valves are they?
M
mysteryman
It sounds to me like a valve - probably the DHW motorised valve - stuck fully open with the end switch 'on'. This will give you these symptoms.
It is possible that you have been running the heating for 5 years with the cylinder thermostat set higher than the boiler thermostat. This will keep the DHW motorised valve almost permanently open, which may have made it stick.
You should have the boiler thermostat set fairly high, and the cylinder thermostat set at about 50C, which is hot enough. This will then shut down when the cyl is up to temperature.
It is possible that you have been running the heating for 5 years with the cylinder thermostat set higher than the boiler thermostat. This will keep the DHW motorised valve almost permanently open, which may have made it stick.
You should have the boiler thermostat set fairly high, and the cylinder thermostat set at about 50C, which is hot enough. This will then shut down when the cyl is up to temperature.
DIYnot Local
Staff member
If you need to find a tradesperson to get your job done, please try our local search below, or if you are doing it yourself you can find suppliers local to you.
Select the supplier or trade you require, enter your location to begin your search.
Are you a trade or supplier? You can create your listing free at DIYnot Local
