Octopus Cosy 12 Heat Pump Regret: Incredibly Loud, Poor Heating & Constant Hum - Help!
The Cosy 9 isn't exactly the strong silent type and I also dismissed most noise complaints as just people being picky. When it is cold and it's working hard, the air noise is very noticeable and we can hear it in our bedroom through triple glazing. We don't get other noises normally - although the TRVs that are closed down some way can whistle some times. I do need to add that it doesn't wake us up or stop us falling asleep but it is definitely louder than I was expecting and I could do without it, as some nights it contributes to me just getting back up again.
@andrewj Can’t recall the original RED designer’s name but I think it is Cassell, he designed the original Dalek like model and this company was sold to Octopus to design and produce ASHP’s in Ireland. I understand that original design was very quiete - what went wrong I wonder? Toodles.
Toodles, heats his home with cold draughts and cooks food with magnets.
@andrewj have you tried a db meter near yours to see how loud it is or isn’t. Tick over we are at 70db, in front of the fan grill it’s over 100db. It’s not cold out so the unit isn’t really pushing to extract heat.
At night we live in a very quiet rural location, i can walk down to the end if the close 40m ish and can hear the gushing wind noise, its not the pump or anything else just this fan going at full wack, i’d describe as putting you ear in front of a white office fan, reminds me of the old prop planes when get ready to move.
i think you have a cosy 9 different beast when it comes to noise, i watched loads of cosy 9 you-tubes and could of lived with that. No one unless deaf could live with this.
i’m 100% octopus will remedy the problem they are a really good company that actually seem to care about people.
@toodles I believe that is the case. At warmer temps, say >4c, it's quiet, and it's definitely not as noisy as reported here for the Cosy 12. I do wonder if part of the issue on my end is that it is running thermostatically: so it comes on, warms the area around the pod up to set temp, then goes off with the temperature of the flow water dropping as well. When it starts up again, it needs to bring that back to temp.
Posted by: @l2jad@andrewj have you tried a db meter near yours to see how loud it is or isn’t. Tick over we are at 70db, in front of the fan grill it’s over 100db. It’s not cold out so the unit isn’t really pushing to extract heat.
At night we live in a very quiet rural location, i can walk down to the end if the close 40m ish and can hear the gushing wind noise, its not the pump or anything else just this fan going at full wack, i’d describe as putting you ear in front of a white office fan, reminds me of the old prop planes when get ready to move.
i think you have a cosy 9 different beast when it comes to noise, i watched loads of cosy 9 you-tubes and could of lived with that. No one unless deaf could live with this.
i’m 100% octopus will remedy the problem they are a really good company that actually seem to care about people.
I haven't and it is definitely not as loud as being reported here. The Cosy 12 is not starting from a whisper baseline though. I haven't reported anything to Octopus as it doesn't really bother us: the instances where I've found it annoying is when I'm struggling to fall asleep anyway! Hot Water is set to run from 2am to 3:30am and I'd expect it to be running hard during that period when it is very cold outside but it doesn't wake us up. But there is a lot of air noise when it's working hard.
@andrewj If this is the case, I rather feel that the pod needs to supply temperature data and then this should be interpreted by an algorithm in the same way as Homely does and makes intelligent decisions about when and how the heat pump reacts. An on/off system just doesn’t cut it does it? Toodles.
Toodles, heats his home with cold draughts and cooks food with magnets.
Posted by: @toodles@andrewj If this is the case, I rather feel that the pod needs to supply temperature data and then this should be interpreted by an algorithm in the same way as Homely does and makes intelligent decisions about when and how the heat pump reacts. An on/off system just doesn’t cut it does it? Toodles.
No it doesn't: as I commented on the Cosy 9 thread, the flow temps on the Cosy systems can't be lowered enough to deal with oversized radiators and "always on" operation. The LSV on my bedroom radiator is open a gnat's whisker and I have a decorator cap on the TRV end and that room is still over 22c (I'm still gradually screwing down the cap.) It would seem that correctness of system design is even more critical with these heat pumps. I can't really control the heat and "setbacks" are not possible, except by turning off the heating. The Primary Pod is in a small room and when the set temp is 19c, the rest of the house is 22.5 - 23.0; when the set temp is 20c, the rest of the house is 22.5 - 23.0; and when the set temp is 21c, the rest of the house is 22.5 to 23.0! Inevitable because the house is being heated based purely on the heat loss and heat gain of that room. I'd also add that with a heat pump, swapping oversized radiators for smaller ones as a fix is mental and having resurveyed a heat loss 1kW less than originally but coming back with a radiator schedule that adds 1kW MORE heat into the house leaves me with a bit of a crisis of confidence in their design team unfortunately. Anyway, that's on the Cosy 9 thread, I don't want to derail this one!
- 27 Forums
- 2,475 Topics
- 56.9 K Posts
- 266 Online
- 6,165 Members
Join Us!
Worth Watching
Latest Posts
-
RE: If a heat pump can only heat DHW to 50C then what? Issue with 18KW Heliotherm heat pump
Hi, Nothing yet. I've asked customer to measure flow...
By errmm , 5 hours ago
-
RE: High Temp Heat Pumps for fast warm-up of house
I don't know exactly how long it takes to heat up (and ...
By JamesPa , 7 hours ago
-
RE: Need help maximising COP of 3.5kW Valiant Aerotherm heat pump
OK. What Im seeing looks fairly normal TBH: 1 start ...
By JamesPa , 7 hours ago
-
RE: Vaillant Tech Support Flagged Low DT: UFH Return Cold, Suspected Zero Flow
@editor thanks for the tips which I will try before cal...
By DavidB , 9 hours ago
-
RE: Daikin 6kw setup with Dixell controller
@jamespa Many thanks for your reply, a very detailed an...
By CraigH , 9 hours ago
-
RE: Exploring the role of alternative clean heating solutions - Government Consultation
Despite reservations, I found some time to respond to t...
By Rusty , 9 hours ago
-
RE: New Vaillant aroTherm Plus in black - When will it come to the UK?
@crankplus, nope, still not, and I've followed up with ...
By Mars , 9 hours ago
-
RE: Octopus Cosy Heat Pump Owners & Discussion Thread
@agentgeorge Probably, but temperature change at -10 ha...
By AndrewJ , 10 hours ago
-
RE: External wall insulation - your experience
To be clear, my experience was very positive. The journ...
By Batpred , 12 hours ago
-
@foxesfan Re: ‘Servicing’ as @editor has covered in his...
By Toodles , 12 hours ago
-
RE: A Smarter Smart Controller from Homely?
@benson No idea why mine doesn’t work, all I see on ...
By Papahuhu , 13 hours ago
-
RE: Battery sizing - How low can you go!
It seems I am seeing something similar to what you do, ...
By Batpred , 14 hours ago
-
RE: Gaslighting in the heat pump industry – has anyone else experienced this?
Don’t know if this is relevant to this thread, but my A...
By Gruff2001 , 14 hours ago
-
RE: Bosch CS5800i 5kW - Experience So Far
@majordennisbloodnok While getting Home Assistant runni...
By Steelbadger , 1 day ago
-
RE: MCS - BS EN 12831-1:2017 – Heat Loss Survey
Since May 2025 it no longer a requirement in England to...
By JamesPa , 1 day ago
-
RE: Air source heat pump roll call – what heat pump brand and model do you have?
Forum Handel @jancold Manufacturer: Daikin Model: E...
By Jancold , 1 day ago
-
RE: Octopus Cosy 12 Heat Pump Regret: Incredibly Loud, Poor Heating & Constant Hum - Help!
@harriworld it was roughly 3am for an hour as that’s ...
By L2jad , 1 day ago
-
RE: Hoped for improvements not being realised on my Mitsubishi heat pump
I have been wondering that myself. The fact is that, ...
By JamesPa , 1 day ago
-
RE: Filtering Tap Water – Share Your Setup for Cleaner, Better-Tasting Water
I remember when I was in my early 20s I was introduced ...
By Majordennisbloodnok , 2 days ago
-
RE: Setback savings - fact or fiction?
But if it is recorded an an integer, which it seems it ...
By cathodeRay , 2 days ago


