Deciphering UFH pump & manifold

[samtheman2k]

Hi all, I moved into a new house last year, with what looks like a polypipe UFH install, with a UPS2 25 40/60 pump. The main boiler is a Worcester Bosch and is working fine.

Last winter, all was well with the UFH, the green light was on the UPS2 and it was circulating water. However, this year there is no green light, nor is it working. I'm trying to work out if it's new pump time, or something else. I've checked the V, and there's 240V to the connector box on the wall. However, some questions:

- Should the pump light be on permanently? It looks like it's controlled by the adjacent thermo sensor, that presumably contains a relay that switches power to the pump when the incoming pipe gets warm. Does that mean that the pump light would thus only be on when the water is not?

- How can I tell if it's the temperature sensor that's broken, or the actual pump? I'm obviously reluctant to replace the pump if it's the sensor that's broken.

- Is this 'normal' setup? Looking at a replacement UPS3, it seems to have a separate control port, rather than switching the power, but I'm not sure if that would be compatible with the sensor I have?

 

[Exedon]

Pump will only run when thermostat opens ie when you have heating warrm enough to switch it.
To be blunt that install is awful those restrictive valves plus flexi connectors?
Have you actually checked if pump is free? Remove large silver screw check with a smaller screwdriver if pump shaft is free.

 

[samtheman2k]

No I haven't....I've assumed if there's no power, it's an immaterial question whether the pump is free or not!

 

[picasso]

Stick the pump on a 3 pin plug and see if it runs, if it does then the sensor if faulty.