Any one have grant aerona HP settings they could copy

[andyj007]

hi all. 

i wonder if anyone could copy me their grant aerona 10kw or other kw settings page.. 

yes im aware that settings will differ bewtween properties, set up install .. 

 

but i would like to check a few settings i have ended up with to try and establish a problem i have or tio ptimise my system .. 

 

thank you

 

Edited November 22 by andyj007

[JohnMo]

You may better listing which settings you have issue with or would like clarification on, to get a response that is meaningful. Asking for a list of 30 to 40 setting most of which are never changed is a big ask, asking for a couple of settings is easy.

[andyj007]

thanks id just like a photo of someones settings book ..    i have issues with Grant ashp going into defrost mode every 20mins when 6 degrees or lower ..  its the same pattern every time ..  as soon as it gets beow 6 degrees ,  , this results on flow temp to the heating circuit never getting above 35d as it coninuously pulls heat from the buffer , just as it starts to get back up it repeats the defrost ..  i dont have this probem on samsung or Nieebe..products ive use before   so as a last attempt before I put this Grant one down to bad decision,   skip it , and replace it with a known quantity   , im going to change all settings as one last attempt and monitor to see if it makes a differrence to defrost .

thanks

 

 

 

 

[JohnMo]

3 minutes ago, andyj007 said:

as soon as it gets beow 6 degrees

That's a strange one. Normally wouldn't start to defrost until below 3. Defrost settings are normally factory set and cannot be altered. The only thing that makes it frost prematurely is running flat out and very high humidity levels. I have attached to original manufacturers manual - Grant bypass a lot of settings, to make installer proof. But you should be able to do a compare to factory setting and hopefully make some sense of what is our of place settings wise.

 

Chofu-Operating-Installation-Manual-R32.pdf

[andyj007]

Thnaks you for teh reply ,  ..I  did run it flat out as this system is only ran at 12am to 7am on cheap electric to charge up the floor for the day . so what im after is the most amount of heat my system can generate in that amount of time ..(cost is not a factor as its 6p kw ) ,  its possible that i shoud turn down the max temp..  whats really strange is that , i dont have this probem when it runs hot water for 1..5 hrs .. which is pretty ,much flat out ..  .. ive not had issues with other brands as i mentioned so this is stumping me somewhat .. 

 

[Beelbeebub]

Is the coil actually getting iced up?

 

The remote display shows the defrost temp (parameter 01-05)

 

Of you are running the unit hard to get mazimum heat into slab at night the deltaT between outside air and the refrigerant evaporation temp will be larger than normal so the outside temp at which the outside coil goes below zero will be higher.  A higher outside temp also means more moisture so even faster icing.

 

Hot water cycle will have a higher output temp and a lower power requirement which might mean the delta T between outside air and evaporation temp is smaller.

 

Basically it might be that your could is getting colder providing 10kw at 35C than 8kw at 45C (figures for example)

 

It's possible you may get better performance by not driving so hard?

[andyj007]

thank you, that certainly is possibility .. its definately gettig iced up  ...

the defrost is set 1-05 is set at 6deg..  in installer mode this cannot be changed ?  ..

 

thank you!

 

Edited November 22 by andyj007

[Beelbeebub]

1 hour ago, andyj007 said:

thank you, that certainly is possibility .. its definately gettig iced up  ...

the defrost is set 1-05 is set at 6deg..  in installer mode this cannot be changed ?  ..

 

thank you!

 

I think that is not something that can be changed, it's a readout of a machine parameter calculated from other parameters eg outside temperature. The parameters nearby are things like outside air temp, compressor rpm etc.

 

Check

01-02 discharge temp

01-08 suction temp

 

My gut feel is the suction temp will be near or even below zero for your heating runs but not quite as low for your DHW (defrost temp might also be lower).

 

 

[andyj007]

Here are the charts from last night .. 

 between 12 & 5 am , 

these are from temperature probs on teh flow and return pipes just as in enters and leaves my plant room.  the pipe work is about 5m  in 28mm to the external wall and heat pump. 

 

 

 

 

[JohnMo]

So random question, your heat pump isn't recycling the air the condenser fan moves.

 

So heat pump located as per manual, nothing in front of compressor to deflect air back etc.

[andyj007]

well thats certainly possible that when below 6 degrees it cant clear quick enough and thats the air point..  but..

yester day it was only -1 - +2 degrees when i re ran the system from 8 am  hours ito middle of the day ish   .. the unit sits in shade ..  so wasnt getting any sun heat ..  this is the graph .  you can see the flow temop gets to just under 50  degree without the limit it gets at night .. 

 

its possible there was less humidity or it was more  breezer in teh day when fired it up   so the condenser air was being blown out a small bit  more ?  

 

Edited November 23 by andyj007

[JohnMo]

I would be tempted to start a new thread titled with issue, most people will not bother looking with your current title. Everyone will see Grant setting and move on. The issue is relevent to any ASHP really.

 

Your issue isn't you need to copy someone elses settings, you have an issue with defrost. 

[andyj007]

just an up date before posting a new thread. 

ive completly factory reset the system and re programmed all the settings .. 

i wont be able to tell if if has made any changes until teh over noight temo drops to 6 or lower.. at which point i will report back under a thread .

thank you all for your suggestions to date .. very much appreciated

 

[Beelbeebub]

On 23/11/2024 at 08:41, andyj007 said:

well thats certainly possible that when below 6 degrees it cant clear quick enough and thats the air point..  but..

yester day it was only -1 - +2 degrees when i re ran the system from 8 am  hours ito middle of the day ish   .. the unit sits in shade ..  so wasnt getting any sun heat ..  this is the graph .  you can see the flow temop gets to just under 50  degree without the limit it gets at night .. 

 

its possible there was less humidity or it was more  breezer in teh day when fired it up   so the condenser air was being blown out a small bit  more ?  

 

Can I clear up....

 

The graph says "underfloor flow".

 

Is it of the flow into your UFH or is it the flow out from your HP? Ie was the 8-12 run getting to 50C a DHW run whilst the midnight to 6am run was for your UFH?

 

Or were they both UFH runs?

 

I assume the first was a DHW run in the basis that 5oC is way to hot for UFH! 😁

 

So some notes

 

The DHW run seems to have some sort of defrost cycle, the little dropouts? Or are they something else?

 

Secondly the UFH run, whilst it has defrost cycles - it doesn't look like those are the limiting factor in the temp output. It looks like the unit is modulating the temp output (the little wiggles) between the defrost dropouts.

 

On that basis I would say your UFH cycle is being controlled to a set temp (40C at a guess) and that is why you aren't getting higher temps.

[Beelbeebub]

You mentioned a buffer. Is this a 4 pipe setup? Ie the HP fills a tank and then the UFH pulls water from the tank via it's own pump and blending valve?

 

Grant often set their HPs up as if they are gas/oil boilers.

 

In this case it might be set up to fill the buffer tank to a set temp.

 

Check parameter 21-00. If that is set to 0 your heating temp is fixed.

 

21-01 gives that fixed heating temp, at a guess 40C

 

If you want it hotter you can change it, but you probably shouldn't put water much hotter than 40C through a UFH setup anyway as you can risk overheating the slab and causing damage.

 

 

[andyj007]

Thanks guys.. 

so the sensors were placed on my flow and return 28mm pipes dircety from teh heat pump. 

 

yes the system goes into a buffer ..  we have a buffer installed as we also have a HW log burner connected into the buffer and HW tank ,  which can be used if we choose.. 

 

the flow to the underfloor  out the buffer would only ever get to 40-45 max due to the loss ..

i have the setting set to climatic curve off so heat temp point which is set at 55 ..    we are not bothered with efficiency as we just need the max amount of heat into the floor in the 6hr overnight cheeap rate ..  which is more than enough for our house needs 

 

it worked perfectly in last night 6hr stint  , but temps were above 6 degrees ..    will have to see if resetting everythinnext time temps drops

 has made a difference .. i have also checked all the stats .. 

i have also sent the chart to grant technical , but the do not understand either .. hence the reset 

Edited November 24 by andyj007