iboost/Eddi vs Immersion timer

[AliG]

It looks like I am set at 62. Hard to say when its just a dial that goes from 1-6.

 

Only used 35kWh today for the pool, compared to 45kWh yesterday. Hard to know if this is because I insulated the low loss header, I turned down the boiler or it was a lot warmer today. 22C vs 13C (lovely day actually). No doubt a bit of each.

 

At 9am consumption overnight was 81% of the day before. This would have been less impacted by the nicer weather. Between 9am and now the consumption was 64% of yesterday's likely more affected by solar gain. The smart gas meter doesn't connect so I have to manually go out and take pictures of the gas meter.

 

A stroke of luck was that all this looking at pipes etc made me realise that they didn't insulate the pipes from the ASHP to the hot water tank in my parents' house before they sheeted the walls. Luckily they haven't been taped and painted yet, that was due to happen this week. The builder was very unhappy about being asked to take off the plasterboard and insulate the pipes, mainly because the ceiling is double boarded.

[AliG]

I should probably move any further discussion of the pool into my thread about my pool.

 

Running the same experiment as yesterday to heat the hot eater back up again.

 

The start temperature was 31.5 and the end temperature was 49.5 at the tap. I think the boiler at 62 may not have been high enough to hit the 55ish where the tank thermostat is set as it seemed to run for a long time.

 

The boiler seemed to use 13.5kWh of gas for a temperature increase that should have taken 10.5kWh, so again 78% efficiency, similar to yesterday.

 

It may be that you cannot get your boiler to run in condensing mode if you want to heat your hot water to 55C, which is where I am set. It probably requires a low-mid 60s flow temp for the boiler.

 

Note my UFH manifolds are set between 38 and 42C so I could run the boiler a lot lower for heating, but the boiler does not have separate temps for heating and hot water.

 

I will try this one more time tomorrow, turning the boiler a little lower and my hot water thermostat to 52C.

 

One of my suspicions is that there is a lot of heat lost in all the little bits of pipework and pumps the water runs through. Thus it is probably more efficient to only turn on the hot water a couple of times a day rather than leave it on from 5am-9pm as I have done previously.

 

It also seems that it will be somewhat cheaper to use the immersion at night on low cost electricity or during the day on PV as it will have much better efficiency.

[AliG]

I decided to purchase an Eddi and Harvi in an effort to maximise the efficiency of my system even if the payback was maybe better on a cheaper timer.

 

Ordered 2/9, delivered 9/9.

 

Took me a couple of hours to get it all installed and set up. Seems to be working but won't connect to WiFi for some reason. It may be because the tank is between it and the nearest router.

 

Install was quite easy as it just required removing the immersion switch and wiring the cables into the Eddi instead. Worst thing about it was tight space and heat in plant room. 

 

Harvi very easy to install, it says to install CT clamps "upstream" of Henley blocks. I found this quite unhelpful. It seems to mean between the meter and the blocks, so before them not after them.

 

I am up now at 3am because just before I went to sleep my wife said she hoped it didn't catch fire. So I clearly woke up to check!