Very hot water but no heating to radiators

[Hmbkr]

Today we discovered that we have no hot water to the radiators but lots of f(airly?) hot water to the tank and taps. The boiler ( an Ideal E Type CF - as old as its Jaguar namesake!) is working. I'm not sure about everything else. The system also includes a Grundfos Selectric UPS 15-50 pump, a Honeywell valve switch, a Potterton EP2000 and a Danfoss thermostat with calibrations in Fahrenheit!

The thermostat can be heard to click when turned up to around 68-70f.

I have no idea about the progammable EP2000.

I am confident that the valve works: I turned the electricity off, then moved the manual selector switch to MAX OPEN then turned the power back on and the switch began to move.

I have also used a rubber mallet on the pump! But I don't think it's working - I can't feel it vibrating.

Where do I go next?

 

[chrishutt]

Check if power is on to pump. If not, look for switching fault (programmer, stat). If power is on, check for pump rotation by removing end cap (silver - small amount of water will dribble out) and insert screwdriver to make gentle contact with end of rotor shaft. If it is rotating, you will hear and feel vibrations as screwdriver makes contact. If not, try engaging screwdriver in slot in shaft end and rotate to free. If this doesn't work, you may need to replace pump.

 

[ChrisR]

You would notice noise from the pump if you switch it between speeds when it's on.
Also, unscrew large central knob or screw (dribbles) to see if shaft within is spinning.
Let us know what you find.

 

[Hmbkr]

The spindle is free so I suspect it's te programmer or thermostat. I can't figure-out how to open the programmer though. I presume the front should come off. Is there a catch, or do I force it off?

 

[doitall]

lift it up from the bottom after you undo the two screws

 

[ChrisR]

Spindle should be SPINNING!!

EP2000's a bit odd . About 3cm from the lower right corner there's a slot about 1/4" long in the groove between the two halves.
Push a flat screwdriver which would fit a number 8 screw up into it and THEN the top half swings upwards.
I think it was one of those clever programmers where you could fold upwards a strip of the case to reveal the connectors for live testing, if that helps.

 

[Hmbkr]

Thanks all. Just replaced the pump and all is well. Will change other bits gradually.