Underfloor heating pump not working

[Podface]

Hi all I have a grundfos ups2 as pictured below. Went in holiday for 2 weeks and came back but the green lights don't light up? Does that mean no power goes to it?

Thermostats seem to work fine.
Checked to see if it was seized up and seems to turn freely with my screwdriver.

Any help appreciated

 

[muggles]

It means either that there's no power going to it (possible zone valve problem) or it's died. Skills with a multimeter needed to determine which

 

[Podface]

It means either that there's no power going to it (possible zone valve problem) or it's died. Skills with a multimeter needed to determine which

Thanks
Checked and power still goes to it looks like the pump is dead.

As an estimate how much would u expect it to cost to replace the head?

 

[Podface]

Another question.
If I was to replace it myself do I isolate the water with the red and blue knobs?

Thanks

 

[muggles]

The UPS2 is no more, now replaced with the UPS3, although the UPM3 is often considered to be preferable in UFH applications.

Turning off the valves in your photo will prevent water getting out of the UFH pipework, which is a good thing, but they don't isolate the pump from the system. There may be other valves to turn off, or you may have to depressurise the system and catch the drips in a tub

 

[Podface]

The UPS2 is no more, now replaced with the UPS3, although the UPM3 is often considered to be preferable in UFH applications.

Turning off the valves in your photo will prevent water getting out of the UFH pipework, which is a good thing, but they don't isolate the pump from the system. There may be other valves to turn off, or you may have to depressurise the system and catch the drips in a tub

Although the numbers are slightly different I'm guessing the
GRUNDFOS UPS3 15-50/65 is the correct one?

 

[muggles]

No. They aren't just a random flurry of numbers, they're important. The 25 on your old pump and 15 on your incorrectly proposed new one relate to the size of the waterways and openings in the pump connections - 25 for 25mm diameter ports and 15 for 15mm diameter. In order to replace like with like, you need to use a pump with 25mm ports. I suggest the UPM3