I have opened all the inlet valves on the Rads , about three were not fully open , but only about three , one turn. I have left the thermostat ends as they are, especially the bathroom & shower room , the lounge dining and kitchen are main living areas connected are fully open . 

I hope this is correct , untill I get the therm. sensors with wires , I can move on.

I changed the flow from 50c to 42 c as previously posted . I do notice the reduced power usage and a drop  in the time the temperature reaches its goal. I need to run that another day as I only changed that midday yesterday.

Graph from Smart meter useful. 

I notice on a pic on page 2 what looks like heatpump gubbins (buffer, tank, pump, pipes) in a cold ventilated loft?

How much insulation is there in the loft generally - these days around a foot depth of fluffy stuff is recommended.

In addition to that, we have 50mm of celotex between our 100mm deep rafters, which stops the worst of cold weather getting to the loft.  Given the amount of hot stuff up there, you might do well with similar?  There’s a 50mm air gap beyond the celotex, all the way down to the ventilated eaves, to ensure the woodwork is happy.

@robl Yes very cold , 300mm all over , but not around tank area , cant feel much heat at all around tank area so all good.

So , update , I have put the flow temp for HP up from previously lowered 42c as The system isnt quite reaching room temperatures as they were. This I have now increased to 46c. The daily costs have come down but not that much on the 42 degree setting , again the weather has changed a little from -4 to 0c. 

I have received the temp probes and will try and suss out flow and return with HP and Rads.

The results with the system passive at the moment and no circ pumps working House/Room thermostat at 20.5c and set for 21c.

HP Return 38.8c HP Flow 40.6c Rads Return 25.5c and flow out 32.6c Not sure what that tell you "bontwoody" Mark?

@alfapat I will be interested to see how the flow and return from the buffer compares with that of the heat pump.

@bontwoody I think I have just sent this in last post.

The heating has just kicked in again 1 degree below setting , which is a tad slow in picking up , however I will wait for a temp change coming up as the programme plan changes up a degree. in 1hour. Have you noticed I have upped the flow temp  in last post.

HP on now and readings are RTN. 38.8 Flow 40.6 RADS  Rtn. 25.5 Buffer out 32.6c

@alfapat Hi Pat, sorry Ive been away for a few days so havent had a chance to catch up.

Im not sure you are doing the radiator valves correctly. The TRV valves should all be set to maximum. You are not going to use these to control the room temperature. The idea is to limit flow to each radiator via the lockshield (balancing valve) on the other side of the radiator. When its set up correctly you will just have the same amount of heat coming in as is leaking out and the room will stay at the correct temperature.

So if im correctly interpreting your thermometer probe data in your last post, the heat pump is producing water at 40.6C and getting it back at 38.8C. Thats a delta T of 1.8C which is low. a DT of 5C is considered to be about right.

More worrying is that the water going to your radiators from the buffer is at 32.6C and being returned at 25.5C. This is worrying because it means that even though your heat pump is producing water at 40.6C, the water getting to the radiators is only 32.6C, a drop of 8C. Thats a massive hit to efficiency. You have to heat your water 8C hotter than it needs to be if you didnt have the buffer in place. I dont have a buffer and the water from my heat pump goes directly to my radiators, at the same temperature.

Are you measuring the temperatures at the pipes where they enter and leave the buffer cylinder? I just want to be sure what I think is going on is correct.

Cheers Mark

@bontwoody Hello , yes I maybe doing this wrong . I have  two temp sensors on the pump lines next to the pumps I will move them to the buffer , and the other two I will move closer as they are on the pipes near the buffer .

Confusing as to why there are thermostatic valves on the outlets in the first place if I have got it wrong , sorry. I think I sent you a pic of lockshield? 😐 

Repositione temp sens. nect to Buffer HP lines 44.3 and 33.1 Rads 40.3 and 33.0

@alfapat some installers try and set up the heat pump to run like a conventional boiler with TRVs. It’s an incredibly expensive way of doing it but easier for people to get there heads around.

@bontwoody So Mark , once you have seen the new temps at tank , how does that work for you. Perhaps adjust the rads, or still work needed at buffer.

@alfapat Sorry, I didnt see the temperature readings. So you are losing about 4C by using the buffer which I think is about an 8% loss in efficiency. If you could manage without it, then it will obviously help. You would need a good installer to make that call though.

Keep working with the radiators to try and get the lowest water law settings that you can, which get you to the required room temperature.

Beyond that, its probably adding radiator size or insulation.

A good monitoring system would help with knowing what is going on, but obviously there is a cost to that too 🙁

Mark , did you get the pic of valve , presumably that is the valve that I will adjust up and down to flow temp, and open the other fully . Would the temp sensors I have now on the buffer tank help judging the flow temps in and out , are they telling you its down firstly to radiator adjustment , then think about flow concerns with buffer?

Were the readings I sent any better with taking nearer tank outlets and inlets. 

I can look at the buffer tank need after a play. 

Monitoring being HOMELY . They don;t price it easily , seems to be good but price is non existant.

Sorry to be a pain , but Thank you! 

Just seen email . Sorry!

Cn you identify a lock shields key , most of what I see a four sided but the ones I have are two sided slots . 

@alfapat 

So this is the lockshield valve

Sometimes they have knurled knobs on which can be used to adjust them, but if not then just use a small adjustable spanner.

You can use the thermometer probes to balence the radiators if you want to. There should be a 5-7C drop from the incoming tail to the outgoing one. I just adjust untill the room temperature feels right.

The buffer issue and the radiators balencing are seprate issues which will both aid your efficiency. The better you can get the efficiency the lower your bills will be. getting rid of your buffer will likely improve your efficiency by 8%ish. Lowering your flow temperature by 5C maybe another 10%ish. Replacing the antifreeze solution with water and anti frost valves another 5%ish. It all adds up.

The issue with removing the buffer tank is making sure that the flow rate is still high enough for the heat pump to function correctly, this is down to the size of the pipes in your heating system and the water pump/s.

Homely takes over the running of your heat pump, but Im not sure how much information it provides, perhaps @toodles  can  help?

Its a lot to take in I know but keep on with the radiator adjustment 🙂