Help with installation / diagram

Some files open on my laptop, but not on my Ipad.


Andy B

Photos as requested - I am in the Scottish Borders - approx 25 miles outside of Carlisle.


Ian.

Oh dear, it is quite cold up there. 20 degree difference is probably not enough.

0.5W/m2/degree. This is serious insulation, and with some air change loss quite a problem to design. You could probably get this under ideal conditions with polyurethane board 100 mm thick ]

An overall U value of 0.15 for walls isn't unknown in some newbuilds these days (yes it means up to about 150mm of PIR/PUR). If the government hadn't got cold feet then something similar would have been in the 2016 building regs. Air change losses are reduced by heat recovery ventilation.

   - Andy.

Well that is a cabinet and a half certainly, double pole 3 phase bus-bar - very German, but in this case Flemish I presume !

To meet UK regs it ought to be in a metal cabinet when it is all over.


OK, so you are stuck with the windows and no money back, if it is  a case of you having a play, there is little to lose here in trying to make some sense of it with some caveats about electrical safety and not cracking the glass,

I suggest as the paperwork is so much cobblers, fist step  if you have a meter and it is your own time, you should test the resistances of the panels, and see if any are actually matching the paperwork, or indeed if any of it is making  any sense at all.  I think I'd expect the watts per square metre of glass too be more or less constant for all the windows.


Reading around, it seems is more common to have triple glazed and the heater on the un touchable side of the inner pane, for room heat or the outer pane for de-icing, which is not relevant here. If they are double glazed, really you have a heater with a single glazed window behind it.

It also seems to be common in other companies to panelize the printing of the heating elements onto the glass into squares or rectangles of constant voltage - it seems these guys missed rather more than one trick.

Now power transformers that give 230V, 110V or 55-0 55V (being a centre tapped 110V ) are the more common voltages readily available, so if things can be persuaded into groups that match those voltages it may be worth a punt for a bit more.

Can you explain a bit more about the sensors though ? is this testing the temperature of the glass - I'd imagine that needs to be limited, or if it cannot be measured,  then heating rates kept very low. Electric underfloor heating does similar, where the floor slab temperature is monitored as well as the air in the room.

Sensors reading gibberish is not encouraging.


 

Lack of CPC to windows is consistent with transformers being intended to make it SELV, but any voltage over 50 would break that. The use of 3 phase +N bus-bar suggests the breakers were supposed to be on primary side, with lots of single phase transformers, and is not really consistent with the drawings.

Looking at the the plans a PT100 is a most unusual choice for the sensor part for a room thermostat, being a platinum wire or strip, that has 100 ohms resistance at 0C.

But the curve is very slow compared to thermistor or diode sensors that are more common. It also means that quite large errors in temperature reading can result from modest extra wiring resistance - really they are normally used industrially for ranges of hundreds of degrees.

It will be worth checking the probe resistances to see if that is what they really have supplied  - look like only 3 of the panes  actually shoud have one.

I've just measured resistance on the windows in the master bedroom and bedroom 1 and all are within 5% of the stated Ohms in the list.

With regards to the sensors - they originally sent NTC15 sensors (these gave false readings - same sensors used in UFH) to be embedded in the frame (3 windows) but subsequently said they were incorrect and I needed PT100 sensors which supposedly just sit on the glass (they never sent any). They did say that the consumer unit came pre-configured and had been 'updated', but evidently the electrical diagrams had not been changed to accomodate this.

Originally it was supposed to be similar to UFH with thermostats but this again seems to be another lie.

It seems the firm involved have been in breach of copyright with regards to the original iqglass who are based in the netherlands. I have spoken to them and their panels are all 240v rated and each pane acts as an individual heater. They said it was not the first time this has happened unfortunately. They offered me a discounted rate if I wanted to replace any but the problem being that the wire installed to the existing windows (2 core) would not be suitable for a straight swop and lack of funds :-(


Ian.

Lack of CPC to windows is consistent with transformers being intended to make it SELV, but any voltage over 50 would break that.

But could be a 'separated' LV system (like bathroom shaver sockets).


OK where there's more than one item of current using equipment on a separated circuit BS 7671 would mutter about supervision by skilled or instructed persons and want unearthed protective conductors, but that's maybe not a real issue if there aren't any exposed-conductive-parts in the conventional sense - besides it might come more under appliance standards which often take a more pragmatic stance to some details than BS 7671.


   - Andy.