sharpener

That would be a nightmare. I read enough posts where the original installer no longer wants to deal with a particular installation (or customer), or they have ceased trading, or the customer just wants to try someone else. If the HP is locked to a particular remote professional account what would happen then?

I have tried Havenwise and admire them for offering interfaces to a whole range of HPs. But I don't understand their business model as £50 p.a. per subscriber is not very much (but probably as much as the market will bear) and from my experience they seem to be willing to devote hours to potential customers who then drop out. (They always knew I had a multi-zone system and initially said they could support it, but couldn't.) On the subject of constancy, I found Zap-map useful but their latest upgrade isn't compatible with the latest OS on my phone. To judge by the (lack of) penetration of OpenTherm in domestic settings I wouldn't hold your breath... Have deliberately stayed away from eBusd and home automation, I fear it would become all-consuming. There are things I keep putting off fixing in the Node-Red routines in my Victron inverter bc there is quite a steep re-learning curve.

I fear it is not as simple as that. Yes with your Vaillant HP you can set the Room Temp Mod to Expanded and the Adaptive Heat Curve to Active then it will over time adapt the WC to the lowest effective value. But these are (a) not the factory defaults and (b) not even in the same part of the menu. This also presupposes that the "thermostat" aka SensoComfort controller is sited somewhere sensible and the installer has configured a whole host of other settings correctly. Some default settings e.g. min OAT shut-off temp are stupid, others like HW offset have no meaning at all for an HP. The dreadful manual assumes a lot of prior knowledge, and is not much better in the original German which I occasionally resort to. Hence the busy Arotherm plus FB forum has a small number of interesting queries but most are from ppl in housing association homes who have had little or no explanation at any level of how HP heating is meant to work or how to control it. And it is clear that HA installation contracts are awarded to the lowest bidder who has no more idea.

We have a 190 m^2 barn conversion on two floors. Original panels are 16 x 230W Upsolar with a wonderful pre-Dec 2011 indexed FIT price. Second tranche is 8 x 405W Longi for which we only get the 15p Octopus export rate. Eventually got DNO to allow unlimited inverter output and unlimited export capacity. Facing due South and with a total nameplate capacity of 6.9 kW we get over 7MWh/year (Devon). Of which 5MWh is exported and almost exactly matches total imports (house is not occupied full time.) Original panels have had no maintenance and the rain in Devon keeps them clean, no significant deterioration in output over 14 years. Battery was originally 2 x 3.55 kWh of Pylontech, quickly increased to 10.65 by adding an extra module. Would ideally add a fourth now that we have a 12kW HP but would mean moving entire stack. Is in rear lobby, not concerned about fire risk beyond getting an "all fires" extinguisher and putting it on the kitchen side of the dividing door. If you are worried then garage would be fine, self-heating will keep the batts warm in winter (we see peak cell temps about 8C above ambient), I would not put them outside in UK climate. @JohnMo's sizing guide is theoretically correct but I think the economics of guaranteeing no import at all during peak tariff periods are questionable, we can achieve this in autumn/spring but not depth of winter. Certainly not worth trying to average over more than 24 hours. We have Victron Multiplus 5kVA/4kW battery inverter (which is excellent if a little bit small, though it does give us whole-house backup) plus a 48V 60A MPPT for the newer panels, and for the others a Solax string inverter (also excellent) replacing the original 2011 Stecagrid one which failed earlier this year. If I were doing it all now I think GivEnergy AIO is worth considering and would go for a 6kW inverter with 15 kWh of batteries and as much solar PV as I could fit.

I don't know if there are any aftermarket WC boxes but there certainly used to be. My introduction to WC was ?late 1990s, we were doing a lot of work converting a house back from 3 flats and somehow I found out about the Danfoss Boiler Energy Manager, perhaps picked up a leaflet in a plumbers' merchant. It monitored the return temp to the boiler and modulated it on and off according to the OAT. No proportional control but even so installing this saved about 1/3 off our gas bill with the original Ideal Mexico. So when we moved to a smaller house in 2008 and then had a loft conversion done (!) I wanted WC but the only small boiler I could find with it was the Vokera Minute. Plumbers were subcontractors of the loft conversion firm and had never even heard of WC. Nor did they think to lag the pipework under the suspended floor. It seems not a lot has changed in the last 15 years...

Yes. And although we need to stop for a PNB and to eat our sandwiches we have a couple of quiet favourite spots for this and not at e.g. the Fleet Services on the M3. And the cost, I can charge at domestic off-peak rates at home even if it takes 4 nights on a 16A outlet.

Yes, my first 4-wheeled vehicle was a s/h Viva van, the tank only held 7 gals which was good for just 200 miles. Which going to the Fringe meant one stop between London and Edinburgh and I knew where all the Jet stations were. And as you say a petrol fill-up only takes 5 mins. ln contrast the EV takes at least 10 for a useful addition to the range and the best part of an hour from empty to full. I have had my fair share of charging points being ICEd in, and having to detour via 3 charging stations late at night before I found one that would accept normal c/cards. That's certainly anxiety-inducing. So it's very handy to be able to get from Cambridge to Romsey and back on one charge.

Same planet as Tesla customers I suppose. Prestige product, exclusive dealer network, similar marketing philosophy. All about bragging rights. Nothing to do with functionality.

Range. Wouldn't have bought an EV if it would not do a regular 270 mile journey without stopping to recharge. Even 3 years on there is still little choice. Given that range is an over-riding property I would have thought even small cars would be more optimised for this factor. But no, even they are optimised for the living-room-on-wheels stuff instead and so weigh a lot more than necessary => shorter range (or larger more expensive battery). Who needs illuminated interior trim with a choice of colour for decor lines all round the cabin?

Electricity Used appears to agree with the dedicated meter in the CU. Ppl on the Arotherm Plus FB group say the heat generated (and hence CoP) are not very accurate compared with energymon. Vaillant have not been able to fix the live power consumption figure on my app which is usually stuck on a standby consumption reading like 11W. I find the app is more convenient for changing the settings than the SensoComfort control which is very clunky. I have added an indicator light panel so I can see at a glance which of the three circuits are actively providing heat.

I would say perfectly feasible. You would of course have to spec the HP with this in mind and also have enough of a thermal load for the contractor to be able to commission the HP in the first place. Main problems I can forsee are more to do with the BUS grant and MCS paperwork than physical installation. The other possibility is to talk to an MCS umbrella company (Aira?) who will spec and commission the system while leaving the actual installation to be done by others (including you). Might be better to ask the mods to move this to the ASHP forum as there is more experience of unusual setups on there. I would say get him to fit isolating valves in strategic places, I would go for full bore quality ball valves e.g. Pegler to be sure they will work when required.

Thanks. Compared with an HP service for £200 I would say you are getting good value. Does that include a new UV lamp? My last one was nearly £100 on its own.

S/h meter for consumption (see under). pH tested with drops from Water for Health, much more precise than any test strips Occasionally more sophisticated tests from Simplex Health Have once had a proper analysis done which showed a lot of iron (in rainwater!!??). 100l per person per day (presumably) strikes me as quite a lot. We had the supply changed at the previous house under a lead replacement programme and kept the old meter - which had a weep from the casing which I fixed with a new O-ring. IIRC they are about £20 at their simplest but of course you can get remote reading ones and no doubt ones that will interface with HA.

Technique I was taught is to wipe a small quantity of compound on the olive only. Nothing on the seats in the nut or fitting. What goes on the (male) thread is 3-in-1 oil which is a better lubricant and does not eventually set solid. But I am not a professional so can spend a little more time per joint. The pre-charge pressure in the vessel also needs to be matched to the operating pressure in the primary circuit, but about 20% less. You have to do this before pressurising the primary circuit. My HP installers left it at the factory setting (3 bar) which is far too high (HP wants 1.2 nom) so it was effectively doing nothing to accomodate expansion and the pressure was all over the place as the system heated up.

I know this is a borehole so different from my rainwater harvesting but am interested to know what treatment processes you have and exactly what servicing they do for your £150.

I think the original fitting is a Polyplumb from Polypipe, but the pipe itself is not polypipe. May be polybutylene from another source, or alkathene. The rainwater system I inherited had a lot of these fittings in it and I think they are quite good, they can easily be undone by hand yet are very positive when done up. Screwfix used to stock them but didn't the last time I tried. Pipe inserts used to be s/steel but later ones were black plastic which have more flow resistance.

Yes but the key word is "eventually" as @JamesPa implies upthread. If individual radiators gurgle or do not get warm all the way to the top turn off all the others to force the air out, doing them one at a time.

Now formally in administration according to tonight's TV news.

Yes, this is a PITA but quite secure. We were with Scottish Power but moved from choice to Yorkshire, they went bust and OFGEM changed us to SP again. Moved to Orbit, went bust, same story. All pretty smooth, getting Octopus to install a smart meter so we could migrate from SP to Cosy was a great deal more time-consuming.

At least as much. Rise from floor to ceiling, more than 5m horizontal run at high level over two doorways, drop down, ~2m run at low level to outdoor unit. None. 28mm to a 4 way split: 3 x 22mm to rads, thermal store and UFH, 15mm to cylinder, all via standard 22mm motorised 2-port Honeywell valves (type 4043, from memory).

Haven't personally encountered this but wonder if @JamesPa has? Have used LM a lot and am confident it is not in there. Fortunately my 12kW runs >2000 l/hr despite 28mm Cu primaries (and as many right angle joints as you) so am still a bit puzzled.

I have always read the graph as showing the remaining pump head i.e. the head available for the building circuit after deduction of what is needed internally to the HP inc. the HX. The max value can be altered in the installer settings according to Appendix C p28 of the VWZ Appliance Interface mfis. And whether it is reached is reported as status S.272 according to Appendix D. Actual flow rate (and much else) can of course be seen in the Live Monitor screens.

Think there is a useful article on the Caleffi web site.

I tend to agree. But the OP has already got the Warmflow so it is a sunk cost and might have a role to play. I don't think they mind the cycling, I used to have a ?80,000 BTU/hr Archie Kidd and it was quite happy running 5 mins on 15 mins off indefinitely. More important was the min temp to avoid condensation, I guess less of an issue with a more modern condensing type.

Don't understand this comment. A thermal store is useful for time-shifting, but that doesn't apply to oil bc the price is the same 24/7. The tariff difference easily covers the loss of efficiency in charging up the TS: at this time of year I am only heating it to 45C which is enough to warm up the bedroom after the cheap period ends at 0700. There are occasional comments about hybrid systems on the Arotherm plus FB group, worth posting a query there I would say. It's possible you would save by running the boiler during peak tariff times and the HP otherwise, but in a new build you might find the thermal time constant is sufficiently long to ride through the peak times anyway.