Odd behaviour from HR92s

[Eniodi]

Thanks for your reply.

I think Resideo lady was suggesting this, so that the pump only runs once the zone valve is fully open. Is this a viable wiring plan also?

[Richard]

You connect the pump exactly as shown in the HCC80R manual and also connect the motorised zone valve as I've shown in our diagram.

[Eniodi]

You connect the pump exactly as shown in the HCC80R manual and also connect the motorised zone valve as I've shown in our diagram.

I've been watching my system like a hawk lately, so I'm seeing all the strange inconsistencies in its behaviour. A few minutes ago I boosted the set point on my main UFH zone. The Evohome controller has been showing a heat demand of 80% for about ten minutes or so for that zone only (all other zones are above set point). The boiler has been running full blast, showing a call for central heating - the pipes are very hot. The actuators on the manifold are almost fully closed and the pump is not running. All rad HR92s appear to be fully closed.

If I had installed a 2-port zone valve operated off the HCC80R, where would the water have been flowing right now? Certainly not through the UFH circuit, and not through any rad with an HR92.

I wonder if Resideo know of this flaw, and that's why they advise against using a zone valve on the UFH circuit. Without the flow through the UFH mixer there would be no flow at all, and you'd have to rely completely on pressure relief (which is far from ideal).

The tech guys insist that when there is a demand for heat, at least one valve should already be open. While that should absolutely be the case, in real world observation that is obviously not true.

Without parroting all the "fuzzy logic" twaddle (a phrase I don't think they actually understand), I'd expect an order of events - a zone set point creates a need for heat, the Evohome controller requests the associated zone valve to open, the controller confirms opening of the valve by return signal, the controller then makes a call to heat from the boiler. Why does it clearly not work this way???

This is another one for me to add to the very long list of undesirable and inconsistent behaviour that I've logged with Resideo. They were supposed to have "escalated" my claims - not heard a word since.

I wonder if the JohnGuest system suffers from this undesirable behaviour..?

[Eniodi]

An update.

The actuators opened and the UFH pump ran (after some considerable time). Then after a few minutes they have closed again and the pump has stopped running. The controller is still showing a demand of 77%, just for that UFH zone only, and the boiler is still running full blast.

I waited a few minutes while this (insanity) continued, then cancelled the set point override, reducing the set point back to below the reported room temperature. In less than a minute the boiler had stopped and the controller was reporting a demand of 0% across all zones.

How on earth is this expected or desirable behaviour?

Is this a comms error? A software error? Not an error at all???

Comms wise - the HCC80R and OpenTherm bridge are a couple of feet apart in the same cupboard. The Evohome controller is 3m away in the adjacent corridor with just a stud wall between. The HCC80R is closer than the OpenTherm bridge. Clearly the HCC80R receives comms, but is not acting as I'd want or expect.

I've been a software engineer and analyst for nearly 30 years. The way this system is behaving is just baffling to me.

[Richard]

Thanks for your reply.

I think Resideo lady was suggesting this, so that the pump only runs once the zone valve is fully open. Is this a viable wiring plan also?

I don't do it like that, because the UFH is separated through UFH manifold anyway and the extra delay time.

[Richard]

An update.

The actuators opened and the UFH pump ran (after some considerable time). Then after a few minutes they have closed again and the pump has stopped running. The controller is still showing a demand of 77%, just for that UFH zone only, and the boiler is still running full blast.

I waited a few minutes while this (insanity) continued, then cancelled the set point override, reducing the set point back to below the reported room temperature. In less than a minute the boiler had stopped and the controller was reporting a demand of 0% across all zones.

How on earth is this expected or desirable behaviour?

Is this a comms error? A software error? Not an error at all???

Comms wise - the HCC80R and OpenTherm bridge are a couple of feet apart in the same cupboard. The Evohome controller is 3m away in the adjacent corridor with just a stud wall between. The HCC80R is closer than the OpenTherm bridge. Clearly the HCC80R receives comms, but is not acting as I'd want or expect.

I've been a software engineer and analyst for nearly 30 years. The way this system is behaving is just baffling to me.

I don't have a system like your specification, so its not something I've had a chance to monitor. I would suggest putting it all in an email to Resideo technical support to escalate and obtain feedback on.

[Eniodi]

Thanks for your reply.

I think Resideo lady was suggesting this, so that the pump only runs once the zone valve is fully open. Is this a viable wiring plan also?

I don't do it like that, because the UFH is separated through UFH manifold anyway and the extra delay time.

True, the UFH mixer pump could run before 2-port zone valve opens without issue. Though looking at how unresponsive and laggy the Evohome system is, I doubt the few second delay before the UFH pump begins to run makes much difference.

[Eniodi]

An update.

The actuators opened and the UFH pump ran (after some considerable time). Then after a few minutes they have closed again and the pump has stopped running. The controller is still showing a demand of 77%, just for that UFH zone only, and the boiler is still running full blast.

I waited a few minutes while this (insanity) continued, then cancelled the set point override, reducing the set point back to below the reported room temperature. In less than a minute the boiler had stopped and the controller was reporting a demand of 0% across all zones.

How on earth is this expected or desirable behaviour?

Is this a comms error? A software error? Not an error at all???

Comms wise - the HCC80R and OpenTherm bridge are a couple of feet apart in the same cupboard. The Evohome controller is 3m away in the adjacent corridor with just a stud wall between. The HCC80R is closer than the OpenTherm bridge. Clearly the HCC80R receives comms, but is not acting as I'd want or expect.

I've been a software engineer and analyst for nearly 30 years. The way this system is behaving is just baffling to me.

I don't have a system like your specification, so its not something I've had a chance to monitor. I would suggest putting it all in an email to Resideo technical support to escalate and obtain feedback on.

Surely mixing rads and UFH is not that exotic? I chose Evohome specifically for this capability. Aside from the question over the 2-zone valve, the rest of it should work as expected. Valves opening when there's demand - the controller reporting some meaningful and reliable numbers.

I've put all this in emails to a Resideo rep, and have a long support ticket. I've just been on the phone to them to kick theirs asses and get someone who has half a clue to phone me (hopefully today).

A lot of me putting this on here is to see if other users are experiencing the same issues, and to corroborate some of this behaviour. I can't be the only person having these issues. Resideo refuse to acknowledge anything - not even discuss the possibility that these are real behaviours. I've been kicked around their support team, and just constantly asked for more evidence. They have given me nothing so far,

Ultimately, though, I did buy all the Evohome components from Evohome shop.... at a cost of over £1000, and it's just not working, at a level beyond just installation and binding. Unless someone can show me otherwise.

[Richard]

Ultimately, though, I did buy all the Evohome components from Evohome shop.... at a cost of over £1000, and it's just not working, at a level beyond just installation and binding. Unless someone can show me otherwise.

Most people forget that we make very small margins on these items, as the evohome product is expensive for us to buy from the manufacturer. If you had bought this elsewhere, you would have paid very similar prices.

I think as a retailer of the evohome product who have not been paid for any technical support, we have done above and beyond most other online retailers responsibilities. No offence, but your installer didn't know how to wire up a zone valve to the system, so I'm thinking what hope did they have of installing and commissioning this correctly?

Like I said, escalate it to the manufacturer and they will no doubt be able to see if the system is operating as they expect or not.

[Eniodi]

Ultimately, though, I did buy all the Evohome components from Evohome shop.... at a cost of over £1000, and it's just not working, at a level beyond just installation and binding. Unless someone can show me otherwise.

Most people forget that we make very small margins on these items, as the evohome product is expensive for us to buy from the manufacturer. If you had bought this elsewhere, you would have paid very similar prices.

I think as a retailer of the evohome product who have not been paid for any technical support, we have done above and beyond most other online retailers responsibilities. No offence, but your installer didn't know how to wire up a zone valve to the system, so I'm thinking what hope did they have of installing and commissioning this correctly?

Like I said, escalate it to the manufacturer and they will no doubt be able to see if the system is operating as they expect or not.

I have escalated it - over and over and over. Resideo are not cooperating, and not putting me in contact with anyone appropriate. I'm still stuck bouncing emails off the trainee advisor at Resideo, who just trickles back lame stock responses from their real tech people.

I fitted and bound the Evohome components while my boiler installer put in the boiler - the only "electrical" parts being wiring in the OpenTherm bridge and the UFH controller by the competent installer. I purchased the components after researching, speccing out the system and specifically consulting Resideo about the zone valve issue. I believe I even made a call to your sales line to go over the required parts before placing the order. My UFH heating system (manifold and piping) was spec'ed out by the local JohnGuest tech guy. How to wire a zone valve was not the question - those questions were from me trying to make sense of all this and why every other UFH controller has dedicated terminals for a zone valve, not from the qualified boiler installer - the question was why there is no support documentation from Resideo, and why they specifically advise against using a zone valve, and whether wiring a zone valve as you have outlined is considered to be in line with Honeywell's warranty (since there is nothing in their installation guidance). You can't really do more than asking their tech directly (now thee separate times).

The boiler installer was not convinced by the Zone valve issue - neither was an ATAG service engineer - but we went on direct advice from Resideo.

Beyond that there is the very long list of odd and unconvincing behaviour from the system in general. Delays in responsiveness, valves not opening, room temperature values changing when the actually temperature can't have, etc, etc.

The real underlying question is not about your technical support here - the original post was a question to all Evohome users to canvas whether these issues are common or not, not technical support as such - it's fundamentally about whether this system works as advertised or not (it seems to work at some level, but altogether very poorly). And if it doesn't, and I can't get any resolution from anywhere, what I need to do next.

Beyond wiring, binding, etc - what other magic is required that only "those in the know" can do?

I'll apologise if this seems like an attack on you. It really isn't. But, I'm at the end of my tether with a very expensive control system that is just not performing, and banging my head against a brick wall with a manufacturer that clearly doesn't give a toss. And this is the only support forum where it seems anyone has half a chance of getting any answers.