Rayburn stove

[Roxie]

Here's one for the thinking Forum watchers.

I have recently installed a Rayburn LPG stove with heating, hot water and cooking facilities. I have separate programable controls for the heating and hot water system and my question concerns the most efficient way to control the hot water. Should I leave the boiler on continuous and rely on the thermostat and the insulation around the tank to regulate the the times the boiler fires up or program the boiler to come on and off at set times to top up the hot water? There are only two of us in house, no kids at home, and hot water demand is quite low.

Any thoughts would be most welcome.

John

 

[cambournepete]

I think this question is applicable whatever your means of heating hot water.
My personal preference is to heat it for an hour or maybe two morning and evening and rely on it staying hot enough at other times. It seems to work for us (2 adults and a child). I don't know whether it's cheaper than leaving the system on all the time, but I feel it must be as the boiler can only operate for a few hours each day.

 

[Steve Maskery]

It's an interesting problem, isn't it?
I would say that it rather depends on when you use the hot water. If you have a bath every morning, then you need hot water then. If you finish a work shift at 2pm, that's when you need the hot water, so there is no point in heating it up for the morning and relying on it staying hot until then. As a general rule, the higher the temperature difference between the water and the ambient surrounding (or is that tortology?), the greater the heat loss. So if you are storing tepid water it's not so inefficient.
Of course, the most efficient is to heat it just as you want it, in a combi, which is no help to you whatsoever, is it?
S

 

[Blister]

I never have my hot water on

I have a electric shower
A dish washer
Washing machine

And if I need to do a small amount of washing up , I boil the kettle

I have the heating set to be controlled by the thermostat ( Heating on continuous on the programmer )
turn the stat up to activate the heating and fully down to switch it off

Works for me :wink:

 

[theartfulbodger]

As a general rule, the higher the temperature difference between the water and the ambient surrounding (or is that tortology?)

It's a rule

The rate of heat transfer is proportional to the temperature gradient.

So it's generally better to heat the water tank up twice a day rather than keep it heated up all day if you need hot water twice a day #-o

Unless you have a combi boiler :lol:

 

[sparkymarky]

i get asked the hot water question alot, so in the summer last year when i don`t use the heating i fitted a hours run meter to the burner on my oil boiler.

i ran the hot water for 1 hour x2 a day for a week then for 7 hours continuous a day for a week then 24 hours a day for a week taking note of the hours run on the burner.

i found that the 1 hour option had the least run time and the 24 hour had the most as was over double the 1 hour times.

however this is just on my system, i have a 12 year old oil boiler fitted to a unvented cylinder in the loft. we have relatively low hot water usage as its just me and the fiancee, a house of five with higher usage may return a different result so i`m afraid the answer is what works best for you, with the rayburn it will take quite a while to heat up from cold so may use a bit of gas before it actually transfers any heat into the water.

are you on a bulk tank or bottles is there any way you can monitor the gas usage i.e. do you have a meter fitted, and do similar tests, in the summer.

sorry to ramble, i hope this makes sense and helps some what. cheers, mark.

 

[Jacob]

Surprised to hear that people are still using them. They (and AGAs etc) are the most impractical and expensive cookers/heaters ever invented.
The first thing you will need is a "normal" cooker. All Rayburn/Aga owners have them eventually, at which point the Rayburn/Aga itself becomes redundant, or a very extravagant form of heating.

 

[sparkymarky]

"normal" cooker. All Rayburn/Aga owners have them eventually

you tell some of my customers that :lol: :lol: they would shoot you then let the spaniels eat you (they would if i said that to them)

but seriously in devon / cornwall many large country houses only have a aga or rayburn burning away on low for 24 hours a day with no other form of central heating, they provide a constant air change within the property keeping the fabric of the house warm and dry stopping damp they the dry clothes at night, provide hot water and boil the kettle / pots and pans and cook tea in the ovens, if used like this then the energy consumed isn`t far out from using night storage heaters, kettles, tumble dryers, extractor fans in the kitchen, immersion heaters / electric showers and electric ovens.

a aga on low uses 2200 liters of oil a year at 60p/liter equals to £1320 which works out at roughly at 15000 kwh at 14p a unit.

it does depend on how you use an aga or rayburn and where such an appliance is fitted if in a modern three bed bungalow then i would quite agree with you jacob, but like so many things individual circumstances does depend on the output energy savings.

 

[PMK54]

IMHO if you don't use a large amount of hot water during the day then keep the boiler off. If your boiler fires up to top up the hot water tank every time, for example you rinse your hands, then for (say) 5-litres of hot water out of the tap your boiler heats not only the replacement water but also the water in its heat exchanger, plus the system pipes and all the surroundings too. If you need large quantities of hot water during the day then manually override the timer.

As for the Cornwall scenario though, the boiler's air flow might give other advantages which you should consider.

Again, IMHO hot water tanks don't have thermostats that are smart enough.

Regarding Combi boilers, they are very efficient but in our area we seem to lose the mains supply about once a year (even though we're in a city not a rural setting) and in such circumstances if we had a combi we would have no hot water. I stand to be corrected on that one if newer combi boilers and their systems have a battery backup as standard (I know you can retro-fit an inverter but that's more stuff to go wrong).

 

[Jacob]

There may well be odd circumstances where heating a half ton lump of iron in one room is a good idea but I can't think of one myself. Just leaving an electric heater on would have the same effect at a fraction of the cost. Or the oven of an ordinary cooker. You can fry an egg at anytime you like on a cooker - often not too easy with a Rayburn!
There's nothing in the posts above which can't be done more cheaply and more usefully by other appliances.
NB 14p a kw is pricy - most of us pay a lot less. My electricity is 12p I think.

 

[Doug B]

The crux of the OP for me was the LPG bit, I`d forget heating hot water with it, other than a bit of back up as it`s got to be one of the most expensive ways. Get economy 7 & an immersion heater.

By the way, what is the heat output from a Rayburn these days, they used to be fairly low, enough for water & a couple of rads if memory serves.

 

[Jacob]

Sorry OP if we have depressed you!
Rayburns are nice though, if you can turn a blind eye to the cost and the impracticality. A bit like having a steam traction engine in the kitchen.

 

[RogerP]

Years ago we lived in a cottage in the Cotswolds and had a "proper" Rayburn, a woodburner, and as wood was free for the collecting in those far off days heating/hot water was essentially free! Happy days

 

[Roxie]

Thanks for all your input it has been interesting to read the various comments.

Doug B. The Rayburn model I have has an output of 60 - 80000 Btu/hr or 17 -23 kW, this will support 16 radiators. I use LPG because we do not have natural gas in the village.

I am leaning towards leave it off until required and let the dishwasher and washing machine heat their own water (they are both on a timer set for overnight on Ecom 7) and override when required.

Thanks for all your comments any more will be read.

John

 

[gus3049]

Sorry OP if we have depressed you!
Rayburns are nice though, if you can turn a blind eye to the cost and the impracticality. A bit like having a steam traction engine in the kitchen.

You don't appear to have used one yourself - correct me if I'm wrong. My wife and I have every intention of getting a wood fired Raeburn as soon as we can afford it. Yes we will have a cheap electric oven and a good 5 burner Neff hob for the summer but.... the main point of an Aga or Raeburn is the way they cook. The water and heating is a side effect.

I used to have an Aga (those were the days) and still miss the way the food was cooked. Our existing ancient DeDetrich wood burning oven is great but not as good as the real thing. Whoever claims that modern electric or gas ovens do as good a job has not experienced the difference. Even toast done on the hotplates is a totally different proposition to a good toaster - we have a Dualit and it just isn't the same.

Although most of us have to be guided by price to a degree, there is such a thing as quality. As with all things in this life, it costs to have the best.

I don't understand how they are impractical or is it just that its always the easiest solution that you think is the best? Sometimes its necessary to work a bit harder for the best results.

 

[Jacob]

Sorry OP if we have depressed you!
Rayburns are nice though, if you can turn a blind eye to the cost and the impracticality. A bit like having a steam traction engine in the kitchen.

You don't appear to have used one yourself - correct me if I'm wrong. My wife and I have every intention of getting a wood fired Raeburn as soon as we can afford it. Yes we will have a cheap electric oven and a good 5 burner Neff hob for the summer but.... the main point of an Aga or Raeburn is the way they cook. The water and heating is a side effect.

I used to have an Aga (those were the days) and still miss the way the food was cooked. Our existing ancient DeDetrich wood burning oven is great but not as good as the real thing. Whoever claims that modern electric or gas ovens do as good a job has not experienced the difference. Even toast done on the hotplates is a totally different proposition to a good toaster - we have a Dualit and it just isn't the same.

Although most of us have to be guided by price to a degree, there is such a thing as quality. As with all things in this life, it costs to have the best.

I don't understand how they are impractical or is it just that its always the easiest solution that you think is the best? Sometimes its necessary to work a bit harder for the best results.

Had one for five years. It was space heater first, water heater second (side tank with lid and tap which you filled with a bucket) and cooker last. Most cooking done on lpg gas cooker.

Yes we will have a cheap electric oven and a good 5 burner Neff hob for the summer

and the winter too - mark my words!

but.... the main point of an Aga or Raeburn is the way they cook.

Nothing which can't be emulated on most ordinary appliances and usually done a lot better. Even the famous overnight porrage is possible on most stoves, but why anybody would bother is another question!

As with all things in this life, it costs to have the best.

Not true and anyway the Rayburn isn't the best - it's just the most expensive! Most cookers you can get for nothing on freecycle will cook better than a Rayburn.

 

[gus3049]

Sorry OP if we have depressed you!
Rayburns are nice though, if you can turn a blind eye to the cost and the impracticality. A bit like having a steam traction engine in the kitchen.

You don't appear to have used one yourself - correct me if I'm wrong. My wife and I have every intention of getting a wood fired Raeburn as soon as we can afford it. Yes we will have a cheap electric oven and a good 5 burner Neff hob for the summer but.... the main point of an Aga or Raeburn is the way they cook. The water and heating is a side effect.

I used to have an Aga (those were the days) and still miss the way the food was cooked. Our existing ancient DeDetrich wood burning oven is great but not as good as the real thing. Whoever claims that modern electric or gas ovens do as good a job has not experienced the difference. Even toast done on the hotplates is a totally different proposition to a good toaster - we have a Dualit and it just isn't the same.

Although most of us have to be guided by price to a degree, there is such a thing as quality. As with all things in this life, it costs to have the best.

I don't understand how they are impractical or is it just that its always the easiest solution that you think is the best? Sometimes its necessary to work a bit harder for the best results.

Had one for five years. It was space heater first, water heater second (side tank with lid and tap which you filled with a bucket) and cooker last. Most cooking done on lpg gas cooker.

Yes we will have a cheap electric oven and a good 5 burner Neff hob for the summer

and the winter too - mark my words!

but.... the main point of an Aga or Raeburn is the way they cook.

Nothing which can't be emulated on most ordinary appliances and usually done a lot better. Even the famous overnight porrage is possible on most stoves, but why anybody would bother is another question!

As with all things in this life, it costs to have the best.

Not true and anyway the Rayburn isn't the best - it's just the most expensive! Most cookers you can get for nothing on freecycle will cook better than a Rayburn.

We disagree on everything - no change there then

My usual comment would have been to suggest you are talking bolloc.s but I'm in a good mood this evening.

 

[Jacob]

Had another one for about 7 years. More modern, plumbed in to heat the water and the living kitchen. That was OK except that running it according to water demand meant that it's cooking capabilities were variable. Rarely hot enough to seriously fry anything on the hot plates, or boil a kettle even, unless the covers had been left shut for a long time.
They were in their heyday up to the 50s perhaps, when they were a good replacement for the open range cookers which were still common even then.
The basic problem is glaringly obvious - the very intermittent high temps required for cooking are so different from the steady relatively low temp required for hot water or space heating.
Hence the Rayburn/Aga style of cookery - anything which requires a long steady cook such as pot roasts etc.
Then it takes an age to bring them up to heat if they have been unlit at all but the craziest thing is that to cook you have to have them on 24 hours a day!!! Some toaster!
If you separate these relatively incompatible functions then things work a lot better.
Slow cooking pot roasts etc are really good in cast iron Le Creuset type pots, on a low light on the gas. Same result, more control, fraction of the price to buy and to run.

PS they have big hotplates and ovens, but if that's what you really want then you can either buy a much cheaper range cooker, or just line up two ordinary ones. We got a Canon Cambridge on freecycle; best cooker we ever had, cost absolutely nothing.

 

[gus3049]

Had another one for about 7 years. More modern, plumbed in to heat the water and the living kitchen. That was OK except that running it according to water demand meant that it's cooking capabilities were variable. Rarely hot enough to seriously fry anything on the hot plates, or boil a kettle even, unless the covers had been left shut for a long time.
They were in their heyday up to the 50s perhaps, when they were a good replacement for the open range cookers which were still common even then.
The basic problem is glaringly obvious - the very intermittent high temps required for cooking are so different from the steady relatively low temp required for hot water or space heating.
Hence the Rayburn/Aga style of cookery - anything which requires a long steady cook such as pot roasts etc.
Then it takes an age to bring them up to heat if they have been unlit at all but the craziest thing is that to cook you have to have them on 24 hours a day!!! Some toaster!
If you separate these relatively incompatible functions then things work a lot better.
Slow cooking pot roasts etc are really good in cast iron Le Creuset type pots, on a low light on the gas. Same result, more control, fraction of the price to buy and to run.

PS they have big hotplates and ovens, but if that's what you really want then you can either buy a much cheaper range cooker, or just line up two ordinary ones. We got a Canon Cambridge on freecycle; best cooker we ever had, cost absolutely nothing.

You were doing something wrong :?

 

[gus3049]

Had another one for about 7 years. More modern, plumbed in to heat the water and the living kitchen. That was OK except that running it according to water demand meant that it's cooking capabilities were variable. Rarely hot enough to seriously fry anything on the hot plates, or boil a kettle even, unless the covers had been left shut for a long time.
They were in their heyday up to the 50s perhaps, when they were a good replacement for the open range cookers which were still common even then.
The basic problem is glaringly obvious - the very intermittent high temps required for cooking are so different from the steady relatively low temp required for hot water or space heating.
Hence the Rayburn/Aga style of cookery - anything which requires a long steady cook such as pot roasts etc.
Then it takes an age to bring them up to heat if they have been unlit at all but the craziest thing is that to cook you have to have them on 24 hours a day!!! Some toaster!
If you separate these relatively incompatible functions then things work a lot better.
Slow cooking pot roasts etc are really good in cast iron Le Creuset type pots, on a low light on the gas. Same result, more control, fraction of the price to buy and to run.

PS they have big hotplates and ovens, but if that's what you really want then you can either buy a much cheaper range cooker, or just line up two ordinary ones. We got a Canon Cambridge on freecycle; best cooker we ever had, cost absolutely nothing.

You also forgot to mention one important thing. The expression "in my opinion" or "in my experience" are perhaps not in your lexicon. Your descriptions of 'problems' ring no bells with me and "in my experience" the way the ovens work is irrelevant. Only the results matter and I always found cast iron to be better than anything else. I have used just about every sort of oven on the market. As an ex kitchen designer / installer, I have had access to most. Oh and we do use Le Crueset and thats the way WE like to cook and it it still better on the Aga - in my opinion.

Have a nice day.