Ball Park cost of Heating Installation?

[ericmark]

In caravans and boats you can have gas or oil fired heaters which can be cheaper to run, much depends on the quantity of oil or gas bought. The small dumpy cylinders of gas work out expensive, but the larger ones are harder to move around, I looked at the one on my sons boat, looked some thing like this and my thoughts were why don't we use them in houses, it is so compact, well it seems they are not efficient enough, building regulations say central heating boilers must be to a set efficiency, and these do not comply, so we jump to a massive unit like this so we are looking at a compromise size v efficiency and how to heat the home at a reasonable cost both installation cost and running cost, and in the main it depends on the size of room to be heated and the time it is heated for.

If the room is only the size of a caravan and your only wanting it heated for a few hours, then the cost of having a heat pump, or oil boilers is likely not cost effective.

The stand alone heater has a big problem, oil or gas are hydro-carbon fuels, and when they burn they make water, so as I found out living in a caravan a heater with no flue makes the caravan damp, and a heater which draws combustion air from inside the living quarters produces drafts. Including the old coal fire.

So the main thing is some where some how you need a flue, and better if a balanced flue, so what can be fitted depends on what can be routed outside.

I have lived where the standard AC looked like this they seemed to fit in a standard box which hung outside, and would both heat and cool, however be it my own or my neighbours, the AC cutting in and out was a noisy thing, and although I did get use to them, it would likely not be liked by your neighbours.

As with all refrigeration units, there are good and bad, and with inverter motors the noise can be reduced, and even the central heating boiler makes some noise, and it does depend where you live, at the side of a busy main road, the sound of a heat pump is nothing, but on a sleepy back water, the noise is a problem, I know those boat heaters made some noise and trying to sleep next to a boat in a marina with one of them running was not the best. looking at the advert nothing about DB or noise produced, mind you neither did the units designed for houses this brochure shows all sorts from oil to pellets to heat pumps, and non seem to say how much noise.

 

[muggles]

OK, thanks. Why would that work out so much cheaper than the current units?

Because direct electric heating uses 1kW of electric to generate 1kW of heat. Heating with air conditioning uses 1kW of electric to generate 3-4kW of heat.

 

[RonnyRaygun]

So is the external unit basically working in the same way as an ASHP?

How many internal units can be run off one external unit?

Just looked up online and one source reckons six times more efficient than standard electric heating. Makes me wonder why these aren’t used more often - at first look it seems like it must be more efficient than radiators run off gas or oil?

 

[flameport]

one source reckons six times more efficient than standard electric heating.

That is unlikely. 3x - 4x or so is more realistic.

why these aren’t used more often

Because most people are still convinced that burning gas or some other fuel is the only way to heat a building, and they either don't know or don't care about the alternatives.

it seems like it must be more efficient than radiators run off gas or oil?

They are and always have been.
However until recently gas has been exceptionally cheap and electricity wasn't, so people chose gas. Efficiency wasn't considered and neither was the source of the fuel.

 

[flameport]

So is the external unit basically working in the same way as an ASHP?

How many internal units can be run off one external unit?

Yes. The difference is that you don't have the air-water part, and no radiators / UFH, which makes air-air systems significantly cheaper and easier to install.
The minor disadvantage is that the internal units do make a tiny amount of noise as air passes through them.

One outdoor unit can supply multiple indoor ones, depends on the heat/cool capacity of each.

 

[RonnyRaygun]

So ball park cost of say, five internal and one external unit, assuming that would be practical?

The external unit would probably have to go on the patio to the rear as I think the land to the side belongs to the flat above. Then I guess a considerable amount of ducting would be required for the units furthest away from the external unit…

 

[flameport]

considerable amount of ducting

Two insulated refrigerant pipes and a cable to each indoor unit.

 

[ericmark]

Makes me wonder why these aren’t used more often - at first look it seems like it must be more efficient than radiators run off gas or oil?

Main reason is noise, but the other is having to renew all the radiators, with a natural air current radiator to cool it needs mounting high, and to heat needs mounting low, so to use a heat pump to heat and cool the house, and little point fitting one which only works in one direction, the radiators need to be fan assisted.

The coolant can be any liquid, but normally a water and anti-freeze mix, but also can be direct from the refrigerant, the problem with the refrigerant is the cost of the stuff, it is claimed to be super safe, but made from some very nasty chemicals, so the plants that make the stuff are expensive to maintain.

In the main down to house design, some where you need to get rid of the heat or gather the heat, so some part of the unit is normally outside, so down to logistics, also when cooling there will be some condensation, this needs dealing with, be it little pumps, or collecting and releasing in a lump so it does not freeze, it is far more complex to a simple central heating system.

The word engineer in the UK normally means some one with a degree, i.e. level 5 or above educated, below that we give tradesmen names like plumber (worker in lead) electrician, pipe fitter, mechanic, etc. We call the guys who design the air conditioning of the home heating and ventilation engineers, as the work of design is very skilled, even just heating if done without costing an arm and a leg takes skill, and I will admit I don't have the skill, and as a result have made errors.

The problem is electric is around 4 times the price of other fuels, so the heat pump at 4 times as efficient is only equal to the other fuels, and we have over the years tried to use other systems to use electric in a cheap way, the economy 7 tariff for example.

And it can work, my brother-in-laws last house had the multi-fuel system, the heart of the system was a pair of very large water tanks on a reinforced floor up stairs, want the tanks high so thermo syphon can be used, so the wood burner, LPG boiler, solar panels, and electric immersion heaters all heated the water in the tanks, which was then used to heat the house, and to be fair it worked very well, he would visit his children in Germany and the house would use no power when he was away, and sense when his phone was approaching the house and reheat his house ready for his return, all built into the house when it was built.

On moving he looked into using the same system on his new house, quoted around £25k, he is 70 like myself, so maximum pay back time 30 years, likely more like 20 before he is dead, and it is simply not worth spending that amount of money to control the home temperature.

Most heating and cooling systems are a compromise, with a standard water circulation central heating system using all Myson iVector fan assisted radiators I am sure one could set it up so each room only heated or cooled when required, using the twin matrix versions even heat one side of house while cooling the other side, but the cost means we don't, main problem is they need a flow at all times, and the gas boiler today does not work that way, but the point is one needs a balance between cost of installation and running cost.

It is the same for most things, no point in getting an electric car if you can't charge it due to design of home, and no point looking at heat pumps if they don't suit the design of the home or your life style.

My son and his wife and children are out all day, so only need to heat house in the evening, I am retired so either my wife or I am at home so needs the heat controlling 24/7. He lives in an open plan house so when heating is on it heats whole house, I have an old fashion house with internal doors, so I can heat room by room. So his heating needs a fast recovery time, a central heating boiler with in living room a standard radiator and a fan assisted radiator plus a gas fire means no need to have geofencing the house warms up that fast, I however have a house twice the size and a boiler half the size, so recovery is slow, I do need to switch on central heating before I return home.

My parents just put on extra coats while opening the doors to allow the cool air out, then lighting fires in the grates using newspaper the draw the fire, and to light the fire, I spent that much time rolling each page of the newspaper and tying a knot in it as a kid, and freezing in my bed room, I will not forget it.

In the Winter of discontent 1978 - 79 I was very cold, as the gas central heating needed electric to work, in the end we had a flueless gas fire fitted, but we said after that no way would we ever rely on electric for heating again, last house had flue brick and gas fire, this house has an open grate, never used, but there in case. If I didn't have a fire, then would be looking at some way to run the oil central heating if no electric, be it a battery powered inverter or a small generator.

After 1978 - 79 the idea of all electric heating I realised was flawed, never again.

 

[winston1]

Just looked up online and one source reckons six times more efficient than standard electric heating. Makes me wonder why these aren’t used more often - at first look it seems like it must be more efficient than radiators run off gas or oil?

They are lying. That is why they are not used more often.

 

[stem]

The biggest issue I see with it is the fact that at the moment the only source of heating is the wall mounted air-con style ones.

You need to define what you are referring to as "air-con style"

1. If it has air-con already then that is a 'heat pump' and will have better efficiency than 'standard' electric heating. [Older models less so than newer designs] Their biggest problems are where to mount the outside unit, noise, initial cost, and their efficiency drops off as the outside temperature falls.

2. Standard convector heaters, are the most expensive to run, but cost peanuts to buy.

3. They could be electric storage heaters. They cost less to run than convectors because they store up the heat when electricity is available at a cheaper rate.

As you have been viewing the flat do the 'particulars' not describe what the heating is?

 

[vulcancontinental]

Energy Cost Comparison - Nottingham Energy Partnership

Different energy sources are measured in different units: kWh, therms, BTU, cubic metres, litres and more. This makes it very difficult to compare the actual costs for powering a heating system between different energy sources. In order to make a fair comparison we need standardised units to...

nottenergy.com

This table is August 2022