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Numerous issues – 11kW Daikin Altherma 3
HI, Just found this forum last night and some of the posters on here have better knowledge then i have found anywhere else. Don't understand alot of it yet but anyway i had 11kw daikin altherma3 low temp split installed last February and moved into the newbuild in June. Only since winter came i have noticed many issues. For past 3 months some rooms were not heating at all but in the last 2 weeks i have figured out stats were wired to wrong ufh loops, have that sorted now thankfully. Installer left me no paperwork and told me nothing about system. Im still thinking its not as efficient as it should be. Some rooms take up to5-7 hours to get up to 21degree setpoint from say19degrees. Only from reading this forum i think my dhw schedule is bit inefficient.
DHW 7am 50deg,2pm 50deg, once a week at5am 60deglegionella cycle. All schedules are 2hours long i think. Reheat set point is at 45 so from reading here im thinking that's too high and may override my ufh flow too much. Im on weather dependent mode but yesterday was 11 degrees and my lwt was 32. Is that bit cold and maybe why my ufh slow? Also noticed my copper flow pipe from unit gets hot but i could go back into room 10mins later and its alot cooler, any reason for this? Apologies about all the questions but i had extreme bills in nov/dec and want to figure this out and this forum seems by far the most knowledagble. Using 70kwhs a day on cold days in a well insulated 2600sq ft bungalow seems bit much. Getting some big spikes especially at night time/early morning. Thanks again.
Would it be any use if i posted installer settings from unit,just figured out how to get into them😀.
Posted by: @newhouse87Installer left me no paperwork and told me nothing about system.
As such your installation doesn't comply with Part-L, sect 7 of the Building Regulations
The installer has to file notifications with your Local Planning Authority (LPA) to demonstrate compliance with the relevant Approved Documents of the Building Act.
At the very least a heat-pump installation falls within Part-L (heat) and Part-P (Electrics).
The LPA has Powers of Enforcement, both for non-filing and for deficiencies in compliance. So your installer won't want them involved.
You should go back to your installer with the above passages which I've quoted, and request that you receive
- a schematic showing the layout of your particular installation
- photographs with labels/descriptions for the controls and valves which are present
- a description of how to adjust the system for optimisation of its efficiency
- a description of the actions required to operate it (what to do if there's a leak, or the water is cold etc)
It isn't sufficient to simply hand over a pile of manuals for the individual parts which comprise your system.
Then tell us here what happened 🤨
Save energy... recycle electrons!
Im getting commissioning cert of them im told here in ireland thats whats needed. My plumber is to email it tonight. Id really appreciate some help just to see if my installer settings are wrong.
On a separate matter, thanks for posting the above photo.
Would you like us to write anything about the levels of pipe insulation which are present on your system?
... or would you prefer to apply a level of common-sense greater than that exhibited by your professional installer, and make some observations yourself?
Save energy... recycle electrons!
@transparent the copper pipes need lagging, that room is quite warm tbf but i take it thats what you mean.
I openly admit i dont know anything but im trying to learn as users here seemed very clued in on the system. Alot of old school plumbers dont know that much unfortunately.
Posted by: @newhouse87Im getting commissioning cert of them im told here in ireland thats whats needed
The Technical Guidance documents of the Building Regulations for Ireland aren't much different to the Approved Documents, as they're called in UK.
What I've referred to in our Section 7 (above) is Sect 1.6.1 in Part-L of the Irish regulations.
Save energy... recycle electrons!
Im sure they have all that, its unitherm who installed it so are a reputable company. The installer hadn't the best english but apparently he installs them around my area. Im hoping its just something simple wrong, so wondering if posting settings, somebody here might spot something simple as i really am trying to learn.
I have learned from just reading here my dhw settings are most likely off so will change that saturday. On nights with work this week so dont want go messing about half asleep.
Posted by: @newhouse87the copper pipes need lagging, that room is quite warm tbf but i take it thats what you mean.
Yup!
That room jolly well should be 'quite warm' with zero insulation on the pipes 😲
For a heat-pump, the temperature differentials are very much smaller than those you'd find for a gas boiler.
Equally, underfloor heating uses lower temperature water with respect to the air temperature of the room.
Combine those two points and you'll quickly realise that the insulation levels for all pipes, valves, sensors and connectors is an extremely important part of the work.
Nothing can be commissioned until the flow & return temperatures are operating under normal conditions.
So zero insulation equates to a system which isn't yet set up.... let alone had its efficiency optimised.
Save energy... recycle electrons!
Feck sake, yeah get whys its so hot now. so i could just lag all the copper pipes. Not sure about me doing stuff with valves and sensors though. He surley checked that flow and returns are within specs. How could installer be that shabby or is it just most people dont question things?
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