Are heat pumps REALLY supposed to be this slow.to heat?

Are heat pumps REALLY supposed to be this slow.to heat?

I kinda understood HPs won't do rapid heating like a gas boiler, but have only had one for about 2 weeks, and winter (still mild compared to what.itll be in a few weeks) arrived this week.

Finding it chilly, I changed the set point to 21 deg C around 6pm yesterday when the thermostat read about 19.2... looking at the glacial speed at which the temperature was increasing, I raised the heat curve to 1.4 from 1.2.

From 6pm to 10am, 16 hours, and there has been a total increase in temp by about 1.7 degrees.

Its a big, 15.5 kw Grant heatpump, the property is not badly insulated, just had under floor and loft and eve insulation put in, taking it to mid C band on EPC (btw, these 3 things, added a measly 4 points to my EPC - went from 57 to 70 with HP, and then 74 with the insulation). I'm fairly confident the heatpump is adequately sized for the property (had 3 separate detailed heayt surveys done, all came.in the 13.5 kw range.

Question really is..to all you HP veterans out there.. is this slow rise the usual with HPs, or.is.my system in need.of.some yweaks

u/User2001Tech — 6 days ago

Would the 25A Shelly Ogemray be OK for a double outdoor socket (UK)

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Thinking of installing a double socket outdoor, for use with things like karcher pressure washers etc. The Ogemray would only be to shut power to the socket when not in use, will not be doing any sort of on/of control on a regular basis. The karchers are usually rated around 1.5 to 2 kw, which is well below the 6kw rating of these - but the whole.inductive vs reactive load thing is making me pause.

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u/User2001Tech — 7 days ago

Wall switch with Shelly behind has stopped working

The mains power in the house was switched off a few times as part of electrical uograde works (only at the Consumer Box next to the meter, nothing downstream inside the huse). After they were done. I found ine Shelly dimmer had completely stopped working. would work through the wall switch, appeared offline in the app.I reset it a few times, it managed to appear for repairing with the app and successfully got added, nut remained offline after that. the light kept blinkng blue... i replaced it with a new one finally

There is another Shelly2.5. 1st gen, installed 6 years ago in June 2020..middle of covid... that has a strange problem now - the wall switch is completely unresponsive - but, it appears online in the app, and I can turn it on/9ff without a problem from the app only - the switch has no effect on it.

after 6 years, I am wondering if its the end of the shelly 2.5, or. is there something obvious I can do to fix it?.

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u/User2001Tech — 25 days ago

Wall switch with Shelly behind has stopped working

The mains power in the house was switched off a few times as part of electrical uograde works (only at the Consumer Box next to the meter, nothing downstream inside the huse). After they were done. I found ine Shelly dimmer had completely stopped working. would work through the wall switch, appeared offline in the app.I reset it a few times, it managed to appear for repairing with the app and successfully got added, nut remained offline after that. the light kept blinkng blue... i replaced it with a new one finally

There is another Shelly2.5. 1st gen, installed 6 years ago in June 2020..middle of covid... that has a strange problem now - the wall switch is completely unresponsive - but, it appears online in the app, and I can turn it on/9ff without a problem from the app only - the switch has no effect on it.

after 6 years, I am wondering if its the end of the shelly 2.5, or. is there something obvious I can do to fix it?.

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u/User2001Tech — 25 days ago

Do these replace tradional levered circuit breakers in consumer unit

hello

getting an electrician to install an outdoor switched socket with RCD as part of a HeatPump install next week.

They will be running cable from the consumer unit to thy HP. 3kW cylinder Immersion Heater. and likely the outdoor switched socket I would like to get installed.

i was thinking of getting a WiFi switch to control the immersion heater, instead of needing to physically press the button. The WiFi fused sockets available on Amazon top out at 13A (e.g https://amzn.eu/d/02eJiPYr), so i initially gave up on the idea..

then found these in Amazon. WiFi enabled CBs

https://amzn.eu/d/07qcfLX9

since the electrician will be signing CB to the consumer unit anyway, these may serve my purpose, asking with adding one for the outdoor socket, so i can disconnect when Sarah in holiday etc.

question is.. do these act as like for like for traditional CBs?. the CBs I have seen have a physical actuator lever that you can drop down to isolate power, these have a push button -

hence the question

a) are these safe/reliable. CE marking gives a bit of peace of mind

b) can they be used instead of traditional CBs. or. should I get them installed in series with a traditional CB?

the electrician will be here only for one day. so i need to order beforehand. can't wait to check with him.

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u/User2001Tech — 1 month ago

Noise level from Hot Water Cylinder

Maybe not strictly fir this forum, but the input on my other queries has been excellent, so..

I have lived with a combi for the last 15 years, so, not really used to pressurised HW cylinders.

Getting a Grant HP with a 250 l QR2 HW cylinder.

The location most convenient is a small cupboard in my main bedroom that we will sacrifice for the cylinder.

Wife has started bringing up the noises the cylinder may make, from water gurgling to valves clicking to pumps running.

I don't wsnt the HP to cause trouble in paradise, so, what is the verdict?.. Are they really disruprive, are the clicks and groans really noticeable?

Thanks.

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u/User2001Tech — 1 month ago

Which tariff to go for with heat pump

Getting a grant r290 15.5 beatpump installed next week, and so, looking at switching tariffs.

I also hvlave a plug in hybrid sith a 50 mile range, that, tbh, i have only charged maybe 5 times in a year, 3 times at home, just used petrol.8f it makes sense, i may also get a ev charget installed if it helps.

A friend who has had a HP for a year advised against the Octopus 3 rate tariff as he bieves the highest rate period erodes the economics.

Any suggestions on who to go for?

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u/User2001Tech — 1 month ago

Electricity consumption - clarification

Looking at switching tariffs in anticipation of heat pump installation. The heat required numbers for heating and hit water, are they supposed to be the amount of electricity I will be importing, or, actual electricity import will be in quarter or so of this (assuming efficiency of 4).

If I plug these as actual electricity consumption, chatgpt gives me an eye watering nunber of about £12000/year, and tells me this isnt nomal for an average 4 bedroom house with a heatpump.

I'm pretty sure the actual elecitricty consumption is the qrtr number, but just want to confirm

u/User2001Tech — 1 month ago

15.5 kw ASHP getting insralled in 2 weeks, which tariff to go for?

As title, my Grant Aerona 290 is getting installed w/c 14th Sep. I'm currently on a BG variable tariff with no exit fee, so. Looking at altrnate providers.

Uswitch etc, dont even bring up Octopus when I look up there. The Octopus site starts with asking gas+electricity, and consumption, (obviously, my consumption profile will change as gas will be used just for cooking, until I can switch the cookers to electricity as well) - and with that it gives me tarrifs with high gas consumption - the cosy tarif lf doesnt even appear in the recommendation.

Questions:

  1. Does the ASHP need to have some sort of smarts/connectivity built in to make use of the smart tariff, abd if so, does the Grant have this built in?

  2. Should I switch tarif now, or wait till after the HO is installed?

  3. Anything obvious I am missing?

Thanks.

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u/User2001Tech — 1 month ago

Heat Survey Report - does it make sense?

Just got a survey report from the 3rd company I have had come and do a survey.

Their heatloss is just under 12 kwatts, with -2.5 degC minimum temperature. The unit theyve offered is 15.3 kwatts, almost 25% oversizing.

I had Heatgeeks come and do a survey yesterday, the guys initial results were just under 12 kwatts with -5 DegC ambient.

Until the HeatGeeks survey, I was leaning towards the 15.3 kw unit, to cater for lower than -2.5 ambient temperature, not unheard of in the north east of scotland.

Does the 25% oversizing have any drawbacks?.. power consumption, cycling etc?

u/User2001Tech — 2 months ago
▲ 4 r/ukheatpumps+1 crossposts

Widely Different Heatpump Sizing.

Hello,

Edit: for clarify, this is for the UK, where Air Sourced Heat pumps are all the rage, no HVAC/Air ducts, no furnaces, the ASHP replaces the exisitng gas or fuel oil boiler to heat water which then flows to existing radiators (though at a substantially lower temperature than the gas/fuel oil boiler used to heat up to).

Need.some.advice. I got a detailed heatpump survey by a company that designs, fabricates, and installs its own heatpumps (dont know. If I can mention the name here). They initially quoted a 12kw system before the heat mapping survey, after I paid the deposit for a survey, this got done. And three days after the survey, I woke up to an email stating my survey deposit has been refunded, no other information. I followed up, and after a few phone calls, was finally told the biggest unit they make is 12kw, and based on the heat survey, my property's heat loss is in excess of 12kw. Their initial sizing was 16.8 kwatts, even after they played with number of air changes (as my property was almost completely renovated in 2021), the lowest it came down to was 13.5 kwatts, AFTER they also excluded my converted garage from the heat load.

The hiuse is around 200 sq m, 4 bedrooms. 1 extra sitting room, large open plan drawing and dining room. All bedrooms are ensuite, though 2 are litrally 0.8m wide by 2 m.long shower rooms. An attached 2 car back to back garage, Which was converted to a study+cinema room in 2021.

I then contacted vendor 2, who did a heat survey, and were very open, they said they improve the number of air changes, size for minimum ambient Temp of -2.5 DegC - With this, the sizing is 11.63 kw. Even jf they increase the number of air changes in the rooms that experience the worst leakage, the size increase to just over 12 kw. , if they reduce ambient to -5 DegC, this increases to 13.3 kw.

Im now a bit worried, the spread of sizing is quite wide. Could some of you in the know. Share there views on

  1. is -2.5 degC a reasonable minimum temp for Aberdeen city?. The property is a detached 1.5 story 4 bedroom house., I'm in the process of upgrading the loft/eve and underfloor insulation

  2. is the performance warranty provided by the vendors worth much - as in. If the system fails to keep the property warm under the parameters, are the vendors obligated to recity at their cost?

  3. Anything else I should look out for in sizing the system.

Regard.s

Rizwan Sher

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u/User2001Tech — 2 months ago
▲ 3 r/PakistanSkincare+1 crossposts

Plz recommend dermatologist, ideally in DHA/Clifton area

Hi,my driver suffers from these terrible sores on his scalp, coupled with him having no hair, it looks very unsightly, which he is acutely aware of, abd now keros his head wrapped in a saafa, which probably makes the situation worse.

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There are time it mostly clears up, and looks like uts al going to be ok, only for overnight flare-up

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I suspect its a derma condition and want to take him to a good dermatologist.... Any recommendations??

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u/User2001Tech — 4 months ago

I keep getting this message - started last year after I installed the shelly. But only happens in summer - shelly app shows temperature reaching 95 degrees, which DOES not happen where I live, or anywhere (unless shelly reports I'm F).

I recall reading somewhere over temperature could be due to lowering swapped, L and N.. or something - any ideas?

u/User2001Tech — 6 months ago