motorised valves replace

maddladd

Hi all a friend of mine had some work done in his house recently and the plumber recommended replacing the mv's as he said they were faulty, also they do not seem able to regulate the temperature in the house, i.e. the stats don't work. The mv's are lying loose on the floor and are not connected to any pipes which i thought they should be so is it really that simple just to switch them for some new ones (which the plumber bought) or does more need to be done. When the stats are turned up one of the mv's seems to light up to show it is activated but i am at a loss to see what they should actually be doing. I thought the plumber should have changed them himself if that was what needed doing?
Thanks in advance

foxboy

maddladd wrote: »

Hi all a friend of mine had some work done in his house recently and the plumber recommended replacing the mv's as he said they were faulty, also they do not seem able to regulate the temperature in the house, i.e. the stats don't work. The mv's are lying loose on the floor and are not connected to any pipes which i thought they should be so is it really that simple just to switch them for some new ones (which the plumber bought) or does more need to be done. When the stats are turned up one of the mv's seems to light up to show it is activated but i am at a loss to see what they should actually be doing. I thought the plumber should have changed them himself if that was what needed doing?
Thanks in advance

I think you need a new plumber, mv's should be connected to pipes they open when a stat calls for heat, or close when stat temp is reached

youtheman

Hey OP, you maybe 'mixing your metaphors'.

Is it the actuator or the complete valve/actuator assembly that is left on the floor ?. Maybe he installed new actuators on the valves, and left the old actuators on the floor (on the assumption they are scrap).

If your thermostats don't work then it has nothing to do with the MVs.

The system (normally) works like this:

Your timer (or panel) outputs 220 Volts to the actator on the MV via the thermostat. So the valve will only open if the timer calls for heat, and the thermostat is closed (i.e. room temp below the setpoint). All the timer/thermostat does is open/close the valve. It DOES NOT turn the boiler on/off.

There is a separate link from the actuator open limit switch to the boiler. So the only thing to tell the boiler to fire is when the valve actuator (or any one of several actuators) is confirmed open.

So if you set your panel to on, and turn the thermostat fully up, you should see the valve open and the boiler fire. Or if the valve is closed and you manually open it then you should also see your boiler fire. Conversly, if you turn your panel off, or turn your thermostat down you should see the valve close and your boiler turn off.

Remember, if you have more than one valve, or zone, then the boiler will fire if any one valve is open (the open switches are wired in parallel).

Hope this helps.

maddladd

Thanks guys, the two actuators are for 1st and 2nd floors, which they cannot cool down, as far as I could see there is one actuator for the ground floor which is working and installed onto a pipe whereas these two are wired up but just lying loose. I can't see any other actuators in the hot press or on any other pipework, so for the system to work properly would these two need to be installed onto the 1st and 2nd floor heat flow pipe where they can be controlled by the stat?

Buford T Justice

Can you take a pic of these and where they are for us please?

maddladd

Sorry it took so long only received these from my lazyass mate!

youtheman

On the top left hand side of the 151 photo you can see one of the valves that has the actuator missing. It is in the vertical position, and has two lugs to centralise the actuator on the valve (its the large brass component in the picture). There is a valve spindle between the two lugs, and this is what is turned by the actuator.

You could always fit the actuator to the valve (but first see what posuition the actuator is, open or closed, and then open or close the valve spindle so that the actuator will fit). I assume there is a second valve missing an actuator, and all you have to do is try figure what actuator if for what valve.

Is there a central control panel that operates these zoned valves?.