HR92 displays E2 error code

[VvrooomM]

I've had Evohome installed for several years, its worked really well after the troubles around set up and the password glitch that caused my controllers to crash when clearing the fault log. Anyway moving on, I still get lots of faults in the log and displayed on the screen but just ignore them unless they relate to batteries as the system seems to work okay regardless. Recently however the HR92 in the bathroom zone permanently displays E2 on the screen. Ive established this is an error and attempted the battery out reset method, which seems to work initially but it then comes back.

How do I clear this error or is the unit knackered?? Oddly it reports the current temperature and to the base correctly but when heat is called for by exceeding the current room temp either by local override or by increasing the zone temp at the base it does not call for heat at the boilew despite showing as much on the base. Current temp will show 15 degrees for example with displayed request at 25 degrees, boiler does not fire.

I actually only need this thing to act like a room stat as the towel radiators come on whenever there is a heat demand, they do not have a individual TRV.

So in summary, can I clear this fault somehow and is it possible just to use the HR92 as a room stat for temp measurement and local override?

[DBMandrake]

According to the HR92 installation guide, Error E2 is:

"E2 valve Motor cannot be moved. Check the installation. If appropriate, remove the dirt."

I'd start by checking that your valve body has not seized up, and that the HR92 base that screws onto the valve isn't broken or jammed.

If you pop the HR92 off and turn the black wheel anti clockwise, can you then turn it clockwise about 1 1/2 turns without too much difficulty or is it very stiff ? If you're not sure how it should feel, try doing the same manual test with the black wheel on a good radiator with the same make of valve body.

When you put the HR92 back on first wind the black wheel anti-clockwise, after clicking the latch wait about one minute then listen carefully while the unit is in CYCL mode - you should be able to hear the motor turning for over 30 seconds. It should gradually slow down at the end. If it sounds like it is straining the whole way through something could be seized up.

If you don't hear any motor activity at all during the CYCL mode but you were able to turn the black wheel ok manually, chances are the motor has failed in the HR92 and you need a new HR92.

Also keep in mind that if you do not click the locking latch over firmly there will be no errors but the device will not try to adjust the valve at all and will also not send any call for heat to the controller. It wouldn't explain the E2 error though.

[VvrooomM]

The black wheel moves freely, the hr92 never enters cycl mode at all though, does this mean that means the motor has failed in two years, or two winters which equates to less than 12 months use. Pretty poor show in my opinion if it has.

[DBMandrake]

If it never enters CYCL mode a minute after closing the latch it more likely means that the switch for the latch that detects when the latch is closed is not working. Try working the latch back and forth firmly a few times with the HR92 not attached to the base making sure it clicks firmly.

One thing you could try is before closing the latch, put the device in Valve pin position mode (change option 10 to 1) then watch the value when you close the latch - it normally jumps to 50 when you close the latch in anticipation of the calibration process. No change in the figure may suggest a problem with the switch for the latch.

[VvrooomM]

If the latch isn’t engaged, it never displays E2 I don’t think. E2 only displayed after unit remounted and latch locked, but CYCL never happens.

[VvrooomM]

In valve pin mode it jumps to 96 but stays there.

[DBMandrake]

Try the valve position test I suggested - if the number does change it confirms the switch is OK.

Another thing you could try is to close the latch without fitting the HR92 to the base. After about a minute it should start the CYCL process despite not being fitted to the base. You should see CYCL and hear the motor turning. It won't be able to complete the calibration (the motor will keep turning several minutes before giving up) but it will at least confirm whether the motor turns at all with no load.

If the motor doesn't turn at all even after a couple of minutes I'd say the motor has died.

[VvrooomM]

The latch definitely works as it triggers a display change from P00 to P96

[VvrooomM]

It never goes to CYCL so I never hear the motor. If it still reports temp, why does this not trigger the base to call for heat and fire the BD91? The bathroom rads are the only rads not controlled so if it just reported temp and then actually called for heat it would be fine.

[VvrooomM]

E2 only displays when latch closed. It shows temp and room when latch open.