@mikeh Our 1930’s semi has internal brickwork, almost everywhere except one short section of studding (more recent mod I suspect); we have MESH wifi and I have had to use five units plus the master to give us good coverage throughout the house and patio area. Regards, Toodles.

I'm also waiting for an engineer visit to be scheduled to come back out to properly test the rads and balance them. Aira have also said they would get someone to call me to adjust the weather compensation. Though they may have done that remotely because I've not seen 60'c flow temps since fitting radiator thermomotors and raising this concern with Aira. The most we see is 45'c but its still only dropping to about 8'c outside so I still think it should be lower. The new thermostat has stopped the house overheating and we've been able to fully open the downstairs TRV's and let the thermostat fully control the heating. The temperature still kicks in before the temperature in the house drops to the target temperature by 1 degree and still overshoots by 1.5 Degrees. But that is much better than before and the energy consumption has come down. I tried balancing the radiators myself to a Delta T of 5 but the end radiators have a temperature drop of 15'c even with Lockshield valves fully open and 2 radiators are not warming up at all. The house is predominantly 15mm push fit which I was told would be fine. I am only learning now about flow rates and will be raising questions with the engineer about potential insufficient flow rate to the furthest rads. 

@mikeh The connectivity specs for Aira indoor units shows Thread 1.3. I was hoping they would use that for the thermostat but apparently not. (I have several Thread router devices around the house).
It also shows Gigabit RJ45. I was hoping to have it connected directly to my LAN. I asked the installing electrician, but he said the only data cable was for their components. I believe he ran a data cable from the indoor unit to the consumer unit to connect it to the Carlo Gavazzi ET340 electricity meter there (via Modbus).

@trungdong That's interesting. The Electrician pointed out what he called a galvanic meter in the new heat pump consumer unit. I notice it has 2 RJ45 ports on it but mine has no RJ45 cable plugged into it, so I assumed it must communicate the energy usage wirelessly back to the indoor unit/cylinder. Has your got a RJ45 cable plugged into the port in consumer unit then? wandering if Aira are not seeing the heat pumps energy usage?

@mikeh In my case, there is a black data cable running between the ASHP consumer unit and the indoor unit. 6 out of 8 twisted pairs go into the Carlo Gavazzi ET340 unit via the bottom ports. The two RJ45 ports at the front are not used.
My app does not show any (energy) "insights" yet. It says it will take about 30 days to collect the data.

@trungdong cool, I may have a little look later. I've now got some insight data visible so I'd assume they must be getting energy usage data to calculate this. This is what it looks like. Also if you haven't seen it, you can now switch to a manual hot water scheduled in a new advanced mode, located in the main hot water button.

Posted by: @editor

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Posted by: @trungdong

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Regarding the quality of a heat pump installation, I wonder if there is a way to get MCS or Ofgem to come and inspect one.

Sadly, MCS and the consumer codes won't do this. There are many new things in the pipeline from a homeowner complaint's perspective and I am working behind the scenes to get the lowdown on the changes. MCS is undergoing a full overhaul to be more effective in dealing with complaints. But as things stand, homeowners are largely powerless if things go wrong and the installer walks. This is an important subject to me, and I've been hammering the MCS, the consumer codes and certification bodies, and slowly, we're starting to see a shift, but it's not fast or effective enough. 

Posted by: @mikeh

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still overshoots by 1.5 Degrees

Posted by: @mikeh

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tried balancing

@johnmo

Posted by: @johnmo

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Looks like you may have started balancing at the wrong end of the system. Maybe caused a preference flow path.

Let's try again!

Update from our Aira install. We've just had an engineer visit to balance the radiators and address weather compensation. We could have been seen last week but we couldn't find a suitable time I could be in. Turns out we had a dodgy TRV that wasn't helping matters and the pump was not dialled up enough. We have all but one radiator getting to the same temperature. We had 50'c rads but he is going to contact the back office team to adjust the weather compensation further. We still have issues getting flow through one new 2M long radiator in the kitchen after several hours work. The engineer has been installing Aira for a while now and said they no longer use the type of pump we have installed. They have been getting less call backs from the beefier pump. He is going to contact the back office to organise for the other type of pump to be fitted. He is also going to speak to their new Heat Geek contact to discuss if we need to upgrade a long 15mm plastic pipe run. It wasn't said, but I'd assume this will likely only happen if the upgraded pump doesn't solve this problem. The rooms involved are tiled so would be quite disruptive and be days of work. Still not signed off the finance to start but not sure I can hold out much longer now.     

Potential quick fix for any Aira Heat pump customer - if Flow temperature feels too warm for the outdoor temperature, using a lot of power, overshooting target temperature:
My Aira heat pump has been working more like a gas boiler, with flow temperatures of 45-50'C. It runs hard at what is probably the maximum fan speed for short periods using up to 4kW of power on my in home display (8kW heat pump). The system constantly overshoot the thermostats target temperature by 1.5'C. I have spoken to several people at Aira to ask them to look if there is an issue with the thermostat and look at lowering my weather compensation curve. I finally got to speak to someone from a more technical background who had access to my data from the heat pump.
He could see the flow and return temperatures at the heat pump where high but the temperature showing at in the buffer tank was much lower. When I explained that I had digital thermometers on some radiators, showing flow and return temps similar to the heat pump temperature, he diagnosed the problem. He believed the temperature sensor on the buffer was not pushed in far enough to accurately read the buffer temperature, so was reading more the ambient temperature. This was making the heat pump over compensate to try and raise the buffer temperature. The solution was was to push the sensor further into the port on the buffer tank (See picture for location).

As soon I pushed the cable for the sensor, you could tell it had more room to be pushed in. I pushed it in as far as it would go and as soon as I did the power usage started to drop, along with the radiator flow temperature. Since then the system has ran more like a heat pump should, low and slow. I've not seen the heat pump power consumption use more than 1.2kW for the home heating and it's no longer overshooting the target temp. I've heard back from Aira that my buffer temperature data is looking much better now.