Trying to make an HR92 out of parts. Can anyone help?

[jweaver]

After years of collecting and repairing HR92s, I now have a couple which are stripped for parts.

I have a room where I want to add this HR92, just as a manual TRV, so I don't want it sync'd to the Evohome (Long story short, I dont' have enough "zones" and this is a room which rarely gets used, so a manual TRV is good).

So I built an HR92 out of parts and it worked fine, but the button doesn't work so I couldn't configure it, but for my purpos1s (i.e a Manual Digital TRV) it was ideal. But one day, it just stopped working and when I reset it, all of the LCD segments came on and I couldn't get it to boot.

After stripping and it looking at the PCB there is clearly some acid/water damage, so I cleaned it and put it on my PCB Heat Plate for a few mins and voila.. it fixed it... But only for a few weeks and then the same fault returned.

So I swapped the PCB out for the other spare but curiously the button doesn't work on this one either... (Odd co-incidence to have 2 button faults on 2 PCBs??)

The switch contact under the button looked fine, but I swapped it anyway, but it didnt' help.. I even buzzed out the tracks and shorted the 2 contacts but can't get the button to activate.

Why is this a problem? Well, it seems that this 2nd PCB is bound to one of my zones.. So when I turn up the heat, one of my rooms does too.. So I need to 'clear' the Binding and I believe I can only do that on the HR92 itself.


I know it hardly worth it, but recycling/repairing/reusing broken stuff is my thing.. And I would like to get some use out of it if I can.

So I either need to work out why the button doesn’t work.. Or somehow "unbind" this faulty HR92.


Does anyone have any experience with HR92s who might be able to help.. I am close to giving up, and just adding this room to my system using a spare HR80, but if I could, I would like to use this "Frankenstein" HR92 I have created.

Thanks in advance

[bruce_miranda]

How about manually shorting the PCB contacts of the switch, just in case the actual switch itself is bad. I had to do this on a RFG100 where the binding button wasn't actually putting the unit into binding mode.

[jweaver]

How about manually shorting the PCB contacts of the switch, just in case the actual switch itself is bad. I had to do this on a RFG100 where the binding button wasn't actually putting the unit into binding mode.

Exactly what I tried (but not sure if I explained it very well). The switch contact "bullseye" is on the back of the board, and you have to plug the screen ribbon in, which is near impossible

So I buzzed out the board and found 2 contacts on the FRONT of the board, through the vias from the back.. But shorting them doesn't not trigger the button action.

My only concluision is that the board has a fault.. But weird that TWO independant boards have teh same fault.

What would be nice is to just clear the memory so I could use it manually..

The bit I don't get is why its sync'd to my living room zone.. I can't imagine I ever bound this one as its always been in my junk pile.. But its not impossible if I have got some of my spares mixed up over the years.

[jweaver]

Pre-Edit.. Ignore this for a min.. My previous post needs "approving", so this won't make sense.. yet.

Edit: I just tried again and I was able to install the ribbon and get access to the back of the board.. its fiddly but it worked and I can confirm, the button contacts are dead.. They don't respond in any way to a short.

So there isn't much I can do... I guess I have to go to plan B which is to use a HR80 instead..

[bruce_miranda]

The only draw back is that the HR80 only ever displays the setpoint. And unless you have an RF interface, you are never quite sure what the room temperature is, ofcourse as sensed by the HR80.

I think in a standalone mode, the HR92 is more useful. Whereas when used with the Controller the HR80 is sufficient.

[jweaver]

The only draw back is that the HR80 only ever displays the setpoint. And unless you have an RF interface, you are never quite sure what the room temperature is, ofcourse as sensed by the HR80.

I think in a standalone mode, the HR92 is more useful. Whereas when used with the Controller the HR80 is sufficient.

Yes.. Painfully aware of this.. Looking to perhaps take an HR92 off an lesser used room and replace with an HR80 so I can use the HR92....

Going to look out for another 'broken' HR92.. I have bought a couple recently with ripped ribbon cables and managed to hard-wire them to the board, so I am getting pretty good at fixing them now..

I think I have wasted too much time on this already. Time to move on I think.

Cheers

Jon

[bruce_miranda]

I note the HR93 is on the way. So hopefully that will drive down prices of the HR92.

[jweaver]

I note the HR93 is on the way. So hopefully that will drive down prices of the HR92.

Ohhhhhhh. Interesting.. I assumed this product line was dead so never thought we would ever see any new firmware, let alone products.... I would love to see a version designed with motor volume in mind as I find the HR92 to loud for the bedrooms, and actually find the HR80 better..I am fed up of waking up almost every morning stupidly early (for me) when they actuate.

So i can live in hope that the HR93 has a different method for actuation.. I would actually buy some at full price if they did, so would end up with some spare HR92s.

Fingers crossed, although am prepared for disappointment.

[philchillbill]

Don't get your hopes up. The HR93 is just a HR92 with the encrypted R3 comms required by the EU. Mechanically I'll bet it's a 100% like-for-like.

[jweaver]

Don't get your hopes up. The HR93 is just a HR92 with the encrypted R3 comms required by the EU. Mechanically I'll bet it's a 100% like-for-like.

Ahhh.. I fear you are right...I have always thought they could do a "Premium" version which could be used in places where noise is important, using something different than a motor to actuate, but I guess there is no demand..

Now I have seen a picture/video of them, they are clearly exactly the same, so as you say, they have probably not re-invented the wheel.

[bruce_miranda]

I am in the minority who still thinks the HR80 is a better product. Even without the fancy display and the lack of battery level notifications, I still prefer the HR80.

[bruce_miranda]

I am also kicking myself that I didn't even think a manifold could be used for radiators. That would completely remove any moving parts in the CH system in each room. I could have so easily done this as part of a floor refurbishment project. Live and learn.

[jweaver]

I am in the minority who still thinks the HR80 is a better product. Even without the fancy display and the lack of battery level notifications, I still prefer the HR80.

I don't disagree.. Whilst I prefer the HR92 for its functionality, the HR80s are quieter and have generally been more reliable.. And with the latest version (2.04) they report battery levels back to Evohome so they are pretty good.. Infact, I have been "downgrading" some of my HR92s to HR80s because of the problems I have had with them...

I think my plan to switch out an HR92 for an HR80 and use the HR92 "manually" in this room is probably the best option.

Thanks for your help.

[bruce_miranda]

I learnt something new today that the HR80 2.04 could show battery levels. All my HR80s are from the CM Zone and Hometronic era, so from even before Evohome was a thing.
I'll have to go around and check if I have any 2.04 versions at all.

[jweaver]

I learnt something new today that the HR80 2.04 could show battery levels. All my HR80s are from the CM Zone and Hometronic era, so from even before Evohome was a thing.
I'll have to go around and check if I have any 2.04 versions at all.

I have my uses .. Yep, the 2.04 version has more functionality, specific to Evohome. Specially battery monitoring.. They do a few more things too, but I can't remember what (I will try to remind myself)

I managed to replace all my 2.03s with 2.04 with a bit of wheeler dealing on eBay, and it works really well, as finding flat batteries randomly is a thing of the past...

Edit: I went back and found the post, and you were the one who told me

https://automatedhome.com/vbulletin/forum/general/heating-control/6706-honeywell-evohome-advice-specifically-gen2-vs-gen3-comparison

But when I read it again, I think I was a bit misleading.. .It doesnt' show "battery level" as such, but it reports "low battery".... So I think you did already know this...