Soldato
Not necessarily. My house was built in the 1930s and is very energy efficient due to double glazing, cavity wall insulation and good loft insulation. My mate is currently renting a 5 year old house and it always feels cold in there.
Hot Water Tank + Boiler vs Combo ?
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Not necessarily. My house was built in the 1930s and is very energy efficient due to double glazing, cavity wall insulation and good loft insulation. My mate is currently renting a 5 year old house and it always feels cold in there.
Caporegime
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i don't see how that is possible. a 5 year old house will have more modern double glazing. better insulation too. the regulations change every so often to make homes more and more efficient. he must not turn his heating on at all or his thermostat is on too low.
you may come to a point in the future where all homes come with solar panels built in and they lose zero heat apart from when you open a window or door or through vents. a 5 year old home should take less energy and time to heat than a much older one (>40 years old) the fact yours was built in the 30's and is warmer means he must have his stat down at 17 degrees or lower.
Soldato
I don't get the hate for "old fashioned" systems personally.
I've lived in a fair few houses last 10 years across both hot water tank and combi, but luckily all of a similar age build, early 2000s
The total costs are misrepresented, people like to say I've saved a fortune by getting rid of my hot water tank. They are wrong, they have saved a fortune by going from a low efficiency boiler to a high efficiency one. Whether they are heating water for rads or water for showers its still cold water being made hot.
Add to that insulation, go back to a nice big fat copper tank full of lovely hot water with no insulation and combine that with a low efficiency boiler and you can see why it cost more to have a tank of hot water there. Now with efficient boilers and efficient storage tanks the cost of it sitting there is low.
We found out recently how good the insulation was, we had the boiler serviced and 3 days later we seemed to have lost hot water as the showers were not hot. Initially I was concerned that the guy who did the service had broken something, when I checked the timer he had turned the heating and hot water off after testing, I assume by mistake.
I've lived in a fair few houses last 10 years across both hot water tank and combi, but luckily all of a similar age build, early 2000s
The total costs are misrepresented, people like to say I've saved a fortune by getting rid of my hot water tank. They are wrong, they have saved a fortune by going from a low efficiency boiler to a high efficiency one. Whether they are heating water for rads or water for showers its still cold water being made hot.
Add to that insulation, go back to a nice big fat copper tank full of lovely hot water with no insulation and combine that with a low efficiency boiler and you can see why it cost more to have a tank of hot water there. Now with efficient boilers and efficient storage tanks the cost of it sitting there is low.
We found out recently how good the insulation was, we had the boiler serviced and 3 days later we seemed to have lost hot water as the showers were not hot. Initially I was concerned that the guy who did the service had broken something, when I checked the timer he had turned the heating and hot water off after testing, I assume by mistake.
Very mixed feelings coming through on here....
Must admit ive always had a combi at all my properties so not come across the old style setup. I have heard combi can be bad for pressures esp for showers and doing something else at the same time although i dont have any kids so cant comment.
Looks like there are props and cons to each system but overall its a draw....
Must admit ive always had a combi at all my properties so not come across the old style setup. I have heard combi can be bad for pressures esp for showers and doing something else at the same time although i dont have any kids so cant comment.
Looks like there are props and cons to each system but overall its a draw....
Are you really only using 4 gallons. Or are you using a lot more without realising it, but that stays in the pipes going cold. Just for you to run it off again when you want want hot water again.
We have 2 boilers (large house) and a 250l Cylinder and its cheaper to run than our old 3 bed semi with a combi.
I will add that we also have secondary HW circulation to we're only a a second or 2 away from hot water at any tap.
Soldato
On a combi it has a max flow rate, same as a tanked system. The flow rate is probably higher on the combi, the question is it enough to cope with your peak. If you could have 2 showers going at the same time you need more peak than if that can only be 1.
The tank has the advantage that you may have say 200 liters so you have a nice large buffer, but if you start using more than that in one go you will struggle.
Often they have a boost button so that it forces the boiler to focus on which ever one you have boosted (for times when you have maybe heating and a demand for more hot water)
I have never looked into load vs efficiency, I assume that like many things (eg PSU) that efficiency isn't a straight line and that high and low demand isn't as efficient as middle ground?
Soldato
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Some boilers pre-heat the water, it has a little tank inside so the water leaving the boiler is immedietly hot. Of course the pipework from the boiler to tap will be cold, but that is no different from pipe from hot water tank to tap has to be wasted too.
Like I said above we have a secondary HW Circulation so the hot water in our pipes never goes cold.. Well never apart from after midnight until about 7am when it all switched back on again.
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That's pretty much the ultimate set up you've got there, I'm jealous.
Caporegime
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also you can buy insulation for hot water tanks it's like £10 from homebase. stupid not to IMO. however any heat lost from the hot water isn't completely wasted. it will help heat your home.
the wife used to use the hot water tank cupboard to dry all our clothes it was boiling in there. having a well insulated door will help too. now that it's insulated it isn't as hot in there and water seems to stay hotter for a lot longer too.
Soldato
That's a valid point as well, although only relevant for say 6 months of the year, and if you have Ac then that has to work harder to cool the house down, not that most in the UK do of course, but in other countries or those lucky enough to have ac
A bit like old light bulbs, yes they used lots of energy but most was converted to heat, so they in effect helped heat the house for 6 months of the year
Caporegime
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That's a valid point as well, although only relevant for say 6 months of the year, and if you have Ac then that has to work harder to cool the house down, not that most in the UK do of course, but in other countries or those lucky enough to have ac
A bit like old light bulbs, yes they used lots of energy but most was converted to heat, so they in effect helped heat the house for 6 months of the year
i live in scotland. what is ac? also our houses require heating for like 10 months of the year
Soldato
Lol I thought the Scots were supposed to be tough, heating 10 months of the year!
Darn sarf however :
Winter (Dec-Feb), heating every day
Spring (Mar-May), probably 50/50, early weeks regularly, late weeks often not on
Summer (Jun-Aug), realistically never on, but always possible
Autumn (Sep-Nov), pretty much the opposite of spring. So far in Sept I think my heating has come on twice, although both times its cos the missue insists on leaving a big window open for the cat to come and go.
Net figure I would say is that approx 50% of the days in the UK (southern regions) no heating is required.
Soldato
Part of the equation is where the boiler is. If it's close to where you're likely to need water quickly (bathroom and kitchen) then losing a centrally located and well insulated HW tank won't be noticed. My mother went combi and had the tank in the airing cupboard removed, and now I've had to move in to look after her I curse that removal daily. Ok, it's nice to have a full pressure shower, but it eats gas to have it running for more than a short time, and it's no use me telling Mum not to turn on a tap in the kitchen while I'm in there because she'll forget as soon as I tell her. So showers can be a lottery. 
I also hate to think how much water we've wasted at the kitchen sink waiting for hot water to come through from the boiler in the garage, and if I had a quid for every time Mum's complained about there being no hot water in the bathroom I'd be able to afford to put her in a decent care home without worrying about the money running out. So, on balance... it depends! But I think overall I agree with those saying that with a good boiler and great lagging, running costs shouldn't be a factor. It's about what suits you and your building's layout.
I also hate to think how much water we've wasted at the kitchen sink waiting for hot water to come through from the boiler in the garage, and if I had a quid for every time Mum's complained about there being no hot water in the bathroom I'd be able to afford to put her in a decent care home without worrying about the money running out. So, on balance... it depends! But I think overall I agree with those saying that with a good boiler and great lagging, running costs shouldn't be a factor. It's about what suits you and your building's layout.
Caporegime
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Lol I thought the Scots were supposed to be tough, heating 10 months of the year!
lol i could live without the heating on all year round. it's the wife that needs it. i normally need to walk around the house naked to compensate