Grundfos Alpha2L issue

[WayneWindsor]

Good afternoon we have recently had a grundfos alpha2L 15-60 130 pump fitted to our central heating system and we're experiencing an issue.
Once the pump is on its working fine but for the first "cycle" in the morning the "Power on" light comes on but the pump doesn't start. I have to then disconnect the mains from the pump and plug it back in and it then kicks in and the pump starts to work fine!!!.
It works okay all day coming on and off at varied prolonged intervals.
Any ideas or help much appreciated.
Thanks Wayne

 

[John.g]

Do any of the LEDs light up, if not, looks like a faulty pump and should replaced under warranty IMO.

 

[WayneWindsor]

Yeah all light up both sides of the power on then they dissappear one by one to leave the pump on but not running??

 

[John.g]

From the manual..... Power On indicated but pump not running.....Check power supply voltage is within specifications Or Pump Blocked.

If the pump displayes the power watts, W, what is the reading and pump mode/setting when it is running?

 

[WayneWindsor]

Would the voltage still be an issue if it runs perfectly after we have turned the power off and on, it's confusing?.
It doesn't have a W display but how would Iho about checking this??

 

[John.g]

Hard to see the voltage being the problem since the pump runs OK after "resetting" If you have a multimeter you could just check the voltage now (while running) at the cable terminals. I think the most likely problem is the pump itself, you could also try and monitor the voltage at start up in the morning.
What setting is the pump on now?.

 

[WayneWindsor]

Would the voltage still be an issue if it runs perfectly after we have turned the power off and on, it's confusing?.
It doesn't have a W display but how would Iho

Hard to see the voltage being the problem since the pump runs OK after "resetting" If you have a multimeter you could just check the voltage now (while running) at the cable terminals. I think the most likely problem is the pump itself, you could also try and monitor the voltage at start up in the morning.
What setting is the pump on now?.

We have tried two settings, the single bar on the left and currently the middle bar on the right.

 

[WayneWindsor]

This is how it's running at the minute.

 

[John.g]

I think that setting is (constant pressure) CP1, a constant 3M head which is a pretty good choice if all rads are hot.
However that should have no effect on your problem. No harm to open the plug and inspect the terminals as I think these are only spring loaded to grip the wires.

 

[WayneWindsor]

From the manual..... Power On indicated but pump not running.....Check power supply voltage is within specifications Or Pump Blocked.

If the pump displayes the power watts, W, what is the reading and pump mode/setting when it is running?

Out of interest what is the power supply voltage specifications for this pump?

 

[king of pipes]

Are you sure the valves above and below are fully open ? The wiring of the pump plug needs attention aswell there shouldn't be any wiring showing

 

[John.g]

Out of interest what is the power supply voltage specifications for this pump?

Nominally, 230V like this one, its on the nameplate.

 

[WayneWindsor]

A number of videos I've watched on YouTube show the pump "upside down" with the waterflow arrow pointing down. I've checked mine and it's the opposite way around!.
Would this have anything to do with my problem and I've attached a photo of the set up to see what you expert's think.
Thanks again for all this help.

 

[John.g]

The pump just comes assembled your way, pumping upwards, if you require it to pump downwards (like mine) you turn the pump 180 deg so as the arrow is pointing downwards and then just remove the 4 studs and turn the head through 180 degrees. Nothing to do with your problem.
As suggested check your harness wiring and probably no harm to shut the pump isolation valves, remove the 4 studs. remove the pump head and backflush the pump from both ends, inspect the impeller, clean with a tie wrap through the vanes if required, re assemble.

 

[WayneWindsor]

I will check the wiring tomorrow, not sure I'm confident enough to start removing and striping the pump, so might have to get it swapped unfortunately.