Boiler water pump for radiators starting to make an intermittent relatively high pitched vibrating noise

[Rollerball]

Couple of interesting things to report:

First I took a look at the valves (which, incidentally, are Lifestyle 679H308-30L1 ).

Both are mounted upside down.

Powered off.

The left one - the black lever very easily moves, no resistance at all. I put it back to its original position after this.

The right one - the black lever encounters fairly heavy resistance - it's not stuck, it just feels like pushing against motor resistance as it will very slowly move. I put it back to its original position after this.

After doing the above I powered back on - the right lever moved a little (resetting itself I guess but was still roughly in the same original position) but the left didn't move on its own.

The water continued to make its usual sounds in the pipes, some very slight humming from the pump, etc.

So as I have a spare, new, TF830.3 control box I thought I'd change that, just to rule it out.

Powered back on and no noise from the pipes ........... (great!).

Tested the boiler, fired it up for half an hour, all working okay, then back off.

Still no noise from the pipes - even better!

I'm hesitant to call it fixed at this early stage, but currently replacing the control box appears to have stopped the water noise from the pipes, no pump hum either. More testing required of course.

One proviso:

I still don't know the cause the the high-ish pitch vibration that I briefly heard a few times late yesterday. Perhaps something in the valves or pump rapidly clicking on/off due to a control box fault? I still slightly suspect the valves or the pump are the cause of that (so not down to control box issues, instead mechanical problems) but we'll see.



Thanks a lot for all of your excellent help so far!

 

[Johntheo5]

switch on the power on the wall, programme both HW and CH OFF, if the pump restarts remove the orange wire from the left hand valve, check that pump stops.

 

[Rollerball]

switch on the power on the wall, programme both HW and CH OFF,

Okay, done that.

if the pump restarts remove the orange wire from the left hand valve, check that pump stops.

The pump didn't restart so ........ I guess that's good?

 

[Johntheo5]

OK, now programme on the left hand motorized valve only, what does this control?,
Then when boiler/ circ pump start up programme it off again and see if both stop.

 

[Rollerball]

Left one is hot water, right is heating (same order as on the main control panel). The 'slides' on the sides of the valves move up/down as appropriate when hot water and heating are seleced so both appear to be functioning okay. Still puzzled why the left one is so easy to move compared to the right (when power is off).

So I guess replacing the control box has perhaps fixed the running on issue?

 

[Johntheo5]

Looks that way but a bit surprised that it has, also, on the Honeywell type of M.valves anyway, if the slider/lever is loose when valve is deenergised then it will invariably lead to the valve passing when other zone comes on or the endswitch will be permanently made. See how it goes anyway and if pump not making any noises, motor on??.

Should have asked, what speed setting is the pump on and is it a Grundfos selectric pump.

 

[Rollerball]

Looks that way but a bit surprised that it has, also, on the Honeywell type of M.valves anyway, if the slider/lever is loose when valve is deenergised then it will invariably lead to the valve passing when other zone comes on or the endswitch will be permanently made.

Not sure what you mean there.

See how it goes anyway and if pump not making any noises, motor on??.

I can feel a slight vibration from the pump when I turn on the boiler (then again I feel the same vibration from the valves too so I guess they are picking up vibration from the pump?) but I can also hear water sloshing around inside the pump so I guess the impeller is spinning. Any idea how to tell for sure?

Also, if it's not working presumably the hot water won't get to the radiators particularly quickly, etc?

Should have asked, what speed setting is the pump on and is it a Grundfos selectric pump.

The pump is a Grundfos Selectric UPS 15-50

I can't see any speed setting? There's no lever, etc.

 

[Johntheo5]

Not sure what you mean there.

Normally if the lever/slider is loose then the valve will pass water when another zone is on because the pump is running with the boiler firing, if there is a problem with your HW valve then might expect to see the HW cylinder to continue heating even when the cylinder stat is satisfied if the heating is on.

I can feel a slight vibration from the pump when I turn on the boiler (then again I feel the same vibration from the valves too so I guess they are picking up vibration from the pump?) but I can also hear water sloshing around inside the pump so I guess the impeller is spinning. Any idea how to tell for sure?

Check water level in the feed&expansion (small) tank in the attic.

Also, if it's not working presumably the hot water won't get to the radiators particularly quickly, etc?

If the heating mot.valve is opened then the rads should heat up normally.

The pump is a Grundfos Selectric UPS 15-50

I can't see any speed setting? There's no lever, etc.

There's normally a switch with I, II and III on it or something similar.

 

[Rollerball]

As for the loose slider/lever on the left valve (hot water only) - so that may be normal for my set up?

As for the last question, I can't see a speed setting switch, etc, anywhere on the pump.

 

[Johntheo5]

Not familarwith those M.valves but would have thought that the slider would start to bite very early on when you move it but doesnt really matter if the valve opens/closes when energised and doesn't pass any water when heating valve is opened.

 

[Rollerball]

Noted, thanks.

Will update this thread if the initial problems return but once again many thanks for your help and detailed explanations.

 

[Johntheo5]

If you wish, you can also remove the pump head by isolating the power, shutting the pump isolating valves, removing the 4 Allen stud bolts and lifting off the pump head
You can then inspect/clean the pump ports and the impeller.

 

[Rollerball]

Very useful to know that, thank you.