No - hotwater is not in the 3rd set of data... just general power around the house which includes the devices listed.

mclean:

 

I assume the third set of data (with the devices on standby/disconnected) includes the HWC demand, so it's going to be pretty unreliable because it will depend on how many HWC cycles there were during the 8/9 hr test period.

 

You really need to repeat the first two tests with everything else disconnected, and maybe run for 48 hrs.

 

The results kind of suggest that the HWC standing loss is very low, and that the thermosyphon through the TLV might be adding about 1.2 kWh/day. But it's pretty uncertain.

 

Some of the mystery is beginning to unfold.

It appears that my house is fed with 2 phases for the uncontrolled stuff

One of those phases is controlled somewhere off my property and feeds the hot water heater.

There is no ripple controller on the meter board. Supply is from Eastland Networks.

When I do phase to phase measurements and phase to neutral measurements I can see that controlled water heating is fed off one of the two phases.

Changes in voltage seen when the water heating is on and off would appear to account for roughly 100 watts variation.

So I need to repeat some overnight tests:

1. Water heating on and all other standby devices on.

2. Water heating off and all standby devices off.

Gordy7: There is no ripple controller on the meter board....

Some smart meters have the ripple receiver built in.

mclean:

 

Gordy7: There is no ripple controller on the meter board....

 

Some smart meters have the ripple receiver built in.

 

Prior to the present EDMI MK10d smart meter (Oct 2016), there was no separate ripple control box.

Again maybe it was built into one the 3 meters we used to have.

I know that when we had loss of water heating, the fault services never visited our house.

Maybe they sent an extra control signal to get the hot water heating going again.

Your hot water usage graphs showed 5 reheat cycles with the valve on, and 3 with the valve off. So it proves what I said earlier on. You are either loosing lots of heat from thermosiphoning, or there is a hot water leak somewhere that you haven't found. Those graphs were misleading as you used a different scale for the Y axis for each graph. 

If it is a thermosiphon issue - It will be a major legionella risk. As those pipes will be sitting at the perfect breeding temp. And the tempering valve will ensure that even when you use hot water, the pipes will never get hot enough to kill off the legionella.

As for measuring the standby loads, you are dealing with complex power factors. What device have you used to measure individual loads? As lots of plug in meters are useless at accurately measuring complex harmonic waveforms.

A bit difficult to see how many cycles the water heating was doing. As I took the readings manually there are some overnight readings missing from the sequence. Excel auto scaled the Y axis of the graphs. Also starting conditions were different for each set of readings and the measurements should have been taken over a longer period.

I have yet to update the tempering valve. However as you say the lower temperatures all around are a breeding ground for legionella. I had the look at the cylinder thermostat. It was pointing to 60C. I raised it by 65C. The pipe at the top of the cylinder now measures 55C.

As for measure the individual power load... Another very rough check... Used one of these:

At present I am doing two over night measurements of my power for all meter loads:

1. All loads on.

2. Water heating off and standby loads off.

Maybe that will reveal more.