Well we now have a weblogger monitoring our Heat Pump. You can see the results here:-

http://www.welserver.com/WEL0412/

Electrical games

Having commented before on the amazing complexity of dealing with the electricity suppliers we have had a rather surreal experience with them.

Having had the 3 phase set up and connected we needed the single phase meter read and removed. This is fine in principle - one calls eon as before and asks. I then find that, even though we called the same number to get the 3 phase meter fitted THIS bit of eon does not know about that. So I have to register the system in order to get the (same) man to remove the old meter (then one calls another bit of the suppliers to get the cable removed - in about 3 weeks).

Not ten minutes after he left I got a call asking me to please tell them the serial number and reading of the 3 phase meter they have just installed ('hey, your man just left...'). Still - this is fine except that the person I am talking to does not know how to read the new meter (clearly labeled 'property of eon') - he feels it should just show the 2 readings alternately (actually it alternately shows time and date). But by pushing various yellow buttons I can get two numbers (but would not a new meter start from zero anyway?). Reading instructions on the meter itself might have been a thought...

I have no faith that there will not be more issues here; for example I pointed out that we are on dual-rate so there are two readings - but he seemed not to be listening. We shall see!

And a detail of useful stuff - there are inevitably small parts of the cold ground circuit showing near the pump - valves, access points etc. These collect condensation and drip a little. But plastic disposable cups mounted on garden wires can collect the drips - which then evaporate anyway from the warm cups!

Fiddling with the controls

Well it all works pretty much, but we have had a fine time fiddling with the settings and may have to make more adjustments before we are done. For unexplained reasons (?concern over local disturbances) the controls favour indirect 'feedforward' control via an external temperature measurement and a fudge factor ('slope') to estimate the heat needed (rather than direct feedback control using the house thermostat). The machine comes with a generic fudge factor of 4.0 programmed, but radiator systems expect a larger factor and we have raised this to 6.0, which may be a tad too high as there may be a slight (less than 0.2 degrees) tendency for the house to warm as the temperature falls, though with a time constant of several days (with up to metre thick stone walls) experiments are not so easy!* We need our WEL data logger. The Alertme power logger works OK (with a few glitches on the software).

And the long time constant gave us an initial problem - the house was very slow to warm up and the HP was not putting in enough extra effort. Raising the fudge factor on the internal house thermostat from 4.0 to 9.0 (in the special menus) to make the system more responsive to house temperature (after all that is what we really want!) helped, as did moving the 'radiator return' temperature sensor (which seems important) onto the radiator return arm and away from the accumulator tank where it was originally sited, but we are warmed up now anyway. The system now thinks the house temperature is 19.5, though 2 local thermometers think only 18.6, but anyway it is quite comfortable.

Other details are that the two oldish Myson fan convectors we had do not much like the water temperature being low - they have a switch to shut them off if the circulating water temperature falls too far (ie in summer as normally arranged). But they have a panel switch that I supposed by-passes this in case you want summer air flow. This is fine but the switch is very counter-intuitively marked, so you need to select the red 'hot' setting (?summer) rather than the blue 'cool' one. We have external room (ie some metres away) thermostats on both units anyway.

I am not sure that the radiator circulating water pump runs 24/7 (as we would wish), though it is mostly on.

Since the HP cycles I am not sure to what extent the efficiency (by physics a function of the temperature increment from the ground and thus of the circulating water temperature) is affected by the mark/space ratio on the cycle, which is what actually varies.

* FYI if you have a similar IVT system we have ended up with a 'slope' fudge factor of 6.0 (default 4), a target room temperature of 20.5 (actually ~19.5) and a sensitivity to room temperature of 9.0(default 5). This seems to work fine.

It works!

So far anyway! I was out this morning whilst it was commissioned but it seems fine and the house is gradually warming up.

Noise is quite moderate, like a loud fridge (& may be above normal anyway).

And the pipe holes are mostly filled and the street hole filled and tarmaced over - so all is well really!

More electricity

Well we are back to commissioning tomorrow (when I will not be here but the plumber and electrician will be), which is probably just as well as the electrician did not in fact change us over to the 3 phase until 5.00ish!

Dealing with the electricity remains by far the most complex task - we now have a single phase meter connected to source but not to our systems and a fully-connected 3-phase system (the inverse of yesterday of course). From here nothing is so urgent but we had to arrange (by ourselves calling yet another bit of eon with yet more numbers - MPAN this time) to get the old single phase meter removed (next week). Only then can we again call the project manager at Morrisons (working for eon) for him to arrange a disconnection crew to take out the old cable (we wonder how much of it - surely not right across the road?). And of course there is also the hole in the road where the joint is to be filled in (see below).

I cannot help feeling that eon would be much better off doing internal central project management, including the ability of any single point of contact to see the whole status on screen and set everything up; easier for them as well as us. The attempt to get the customer (us) to make all the phone calls to different people to set up different jobs in sequence surely just adds to the confusion!

Almost there!

The connect team did connect the 3-phase power as far as the meter box yesterday (fortunately/kindly they did not disconnect the single-phase as their jobsheet said!); but the quick meter-install that sounded so good was much more problematic.

I spent a prodigious amount of time on the phone yesterday to various parts of our electricity supply company (eon) in multiple calls. Everyone (particularly Sean & Rosie) was very helpful but the system is deeply flawed - several degrees below shambles! No-one seems to know who can authorize what and people are on the phone to endless lists of other people who keep passing them on! Frustratingly but fortunately we did have the direct phone of the emergency team who put in meters but they need authorization...

We did finally get a call at nearly 5.00pm to say a meter installer would call in the next 4 hours! This may have been more the effect of the original meter-installer's report than of our calls. Unfortunately I was by then at a meeting in London (ironically on the resilience of UK infrastructure!), and our electrician was running out of time.

But they did come about 7.45pm - no-one here of course, as we had pointed out, but the box is outside so he did not need access. Unfortunately no-one had told him that so he left a card! Thank Rosie we knew the direct line for the emergency people and were able to recall him - and it finally got fitted 10.30-11.30pm last night. He was helpful (it seems he does nights on a rota and was heading home afterwards) and we plied him with coffee and we are potentially on course for commissioning today!

Not such a good day!

Well the crew came back (albeit not exactly 'first thing'!) but were unable to get the right cable into the wrong duct - it is a pretty tight fit. They also managed to leave it with no rope through.

After they left another crew came who also could not get the right cable through the wrong duct. They stayed for some hours after which another crew came who could not do it too, and are now digging up the road again (without lights this time) to put the right duct in.

Oh - and the meter box was the wrong way up - but we have now fixed this!

Meanwhile the existing boiler is out - so no heating!

And the man came to change the meter - helpful but obviously nothing for him to do (so the initial crew did not tell him as promised). Still, they have been quite helpful and we have a number to call to get an emergency meter fit at 3 hours notice.

***

Well the self-proclaimed A-team did get the correct cable and duct in OK, and the joining team should be back 8.00am tomorrow, so we are about 24 hours behind on the 3-phase supply but should still be OK. Meanwhile the plumbing is pretty much done and the circuits filled. So we have ended on a more positive note!

First signs of 3-phase

Well they have dug the hole across the road and covered it over - though I noticed that the cable they had installed was single-phase! They agree and now expect to be back Monday am to replace it - they hope by pulling the (rather fatter 3 phase) cable through the duct. I note that their duct is considerably thinner than the 100mm one they got us to put in!

Our electrician has put in a good many cables but was not back today as anticipated - he thinks he is OK to complete Monday am (looks a bit tight to me!).

Commissioning on Thursday! ICE tried to change this to Wednesday or Friday but we said no - too many other people involved.

Pipework started

Well after a hiatus (not quite as long as it looks - the plasterers have been fitting foam-insulated plasterboard under the sloping roof ceilings that are universal on the top floor as this is the only way to improve the insulation) the plumbers are back and fitting this Tardis-like arrangement. It is fine except that the elaborate effort to make sure that the ground loops nearest the house are on the return (warmer) side went wrong so they will have to fit pipes swapping this round!

The heat pump has fittings for hot water that we are not using (which seems a waste) & we will just join these up to seal them (Ice Energy say one could blank them). The programming should ensure that they are never used.

3 phase power is due on 18th, with commissioning on 21st (the old boiler will need to be removed between these dates).