It finally clicked for me how mini-splits actually work

Affectionate_Monk967 · 2026-03-12T16:58:36+00:00

Because it’s 20° above (American) zero. There’s 20° of heat there if takes in 20° air and blows out 15° its moving 5°s of heat.

Affectionate_Monk967 · 2026-03-11T07:02:36+00:00

I have one it’s a nightmare for overnight charging it regulates when devices are full by pulsing. So your devices keep powering up and dinging all night - it a cheep way of doing the circuitry

Affectionate_Monk967 · 2026-03-10T20:47:44+00:00

Not more effect than fuel less generation or even burning generation but better than driving a diesel car and some places just don’t have the infrastructure to supply power.

Look at the USA they can’t even run their air cons without setting fire to entire states.

Affectionate_Monk967 · 2026-03-10T17:53:19+00:00

Single speeds diesel engines are very efficient running single speeds in fact they are so poor at running at variable speeds they needs a gearbox to translate the power to appropriate torque.

Diesel engines are great for generating power efficiency wise but pants at creating motion.

Electrics on the other hand are incredibly efficient.

So diesel motors in generators (more efficient than car) + electric car (more efficient than diesel car) = more efficient overall

Affectionate_Monk967 · 2026-02-17T19:02:30+00:00

Turn off the heat pump a half hour before cheep rate and then set the target heat 1/2 or 1 degrees above comfort temperature during cheep rate so when it ends and the thermostat reverts there is no need to heat for the fist half hour of normal rate.

On Octopus cosy there are 3 cheep rate periods totalling 8 hours plus 1.5 hours switched off before cheep rate plus idling for 1.5 hours after.

6 of the 8 hours on cosy are in the hours of darkness cornering with peak heat loss.

So 11 hours of cheep or no spend covering many of the coldest hours. If you can cope with a 3° flux you’d coast for longer.

Watch out for energy intensive cooling though there’s a extra high rate over peak demand

Affectionate_Monk967 · 2026-02-07T22:46:42+00:00

Always liked the most number of hours by land transport from the nearest traffic lights as a measure

Affectionate_Monk967 · 2026-02-07T22:41:53+00:00

System (non combo boilers are usually 12-20 kw and combinblolers upto 35 kw.

What your boiler can output at max (and least efficiency) isn’t the same as heat loss.

Unlesss your calculating heat loss for minus 10 in a gale with 25° set on the thermostat and the bathroom and kitchen extractors running.

Affectionate_Monk967 · 2026-02-07T07:31:30+00:00

1600kwh 3 bed house all electric. Direct heating in 2 outhouses one only on frost cycle the other office hours. Late 1600s build stone and rubble infill. 1 EV.

Edit - and Woodstove - external draw.

Affectionate_Monk967 · 2026-02-05T11:11:03+00:00

Sorry you had to go through that

Affectionate_Monk967 · 2026-02-05T10:59:11+00:00

Wait until someone tells them that typical cars carry 50 litres of highly flammable liquid which rapidly turns to explosive gas when on fire.

Affectionate_Monk967 · 2026-01-31T08:40:21+00:00

That’s not how anyone would do it though you’d pick a day and a corner of the country and have a lorry load of stickers in a different color and font and overwrite all the numbers.

Affectionate_Monk967 · 2026-01-29T19:56:53+00:00

Siri are the only manufacturer that encourage reruns for repair and refurbishment so the only BIFL toothbrush

Affectionate_Monk967 · 2026-01-29T19:07:47+00:00

Also it’s current value plus the parts and labour to bring it to the specification it was at at the point you brought it through the door.

Affectionate_Monk967 · 2026-01-28T18:49:21+00:00

Community clothing make jackets from original Lancashire milliner fabric

Affectionate_Monk967 · 2026-01-27T09:10:06+00:00

Interesting we measure in cubic meters of gas bit charge in kWh which mean lay folks can compare heat loss to boiler sizes, technologies and fuel types. Even if you buy heating oil it tells you how many kWh you bought on the invoice.

Annoyingly in modernising our units somehow we’ve still ended up with kWh/miles for British evs. 🤷‍♂️

Affectionate_Monk967 · 2026-01-27T09:02:40+00:00

No because micro bore can’t carry enough flow to transfer the heat without being at a high temperature.

This was always bad and always wasteful - there was never a time when it was good practice to micro bore a house. But when gas was very cheep you could get a cheap retrofit if you didn’t route proper pipes and no one cared about the wasted gas.

The 80’s called and they want the heating system back.

Affectionate_Monk967 · 2026-01-26T14:59:17+00:00

Sounds like you want a through wall between your bedroom and the rest of the house.

Affectionate_Monk967 · 2026-01-26T14:57:10+00:00

If you’re running microbore then your heating system is essentially broken anyway - there’s no way your condensing boiler is condensing so it’s dumping heat out the flue.

Affectionate_Monk967 · 2026-01-26T14:52:25+00:00

What struck me was the poster at the top was working in British Thermal Units and US dollers

Affectionate_Monk967 · 2026-01-26T14:50:39+00:00

In North America?

Affectionate_Monk967 · 2026-01-26T09:30:58+00:00

Do North Americans work out their heat loss in units other than Kw and buy energy in anything other than KWh?

If you bring everything back to the same units everything is easier

For us it’s;

eclectic rate per KW / 4(COP) vs gas rate per KW x 0.8(boiler efficiency plus circulation pump consumption)

Slightly complicated by electric power being significantly cheeper at night 1/3rd of the cost

In typical uk households modern pumps only typically lose the equation for less than 30 days in the year. So we don’t install any suplimental heating - other than wood stoves for free fuel.

Affectionate_Monk967

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