Perhaps you should invest in a printer for your computer IMM. They are surprisingly cheap these days. That way you will be able to file away copies of Andy's most informative posts much more quickly, and it will save you all that scribbling with the crayon....
Out of interest, why the crayon? Do they not allow you sharp objects?
Yup, that's what I concluded after spending a lot of time trying to eliminate the short cycling. Put in the heatbank and presto, problem solved.
I do like the other advantages too. When the CH comes on, it takes no time at all for the rads to heat up. Also we now have 'mains' pressure HW to all the taps + showers, which means quicker bath fillups.
Ensure you get the right model. Most Greenstars require a sealed pressurised circuit. I believe that the Greenstar HE29 "Conventional" is the model you need.
Sounds like you want to configure as S-Plan Plus. When designing the layout, for maximum future versatility, run an unzoned "main" round the house and put the zone valves where the actual zone circuit starts. This way you can add new zones easily, rather than having to route a pipe all the way to the boiler.
Christian.
It is called a "heating" boiler.
Sounds like he should no such thing. He needs an "integrated" heat bank and run the rads off the heat bank. Boiler cycling is eliminated. Run the heat bank between 72 - 75C and set a primary blending valve to 54C.
You can (and should) zone the radiator circuits even when they're run off the heatbank, you know!
Christian.
You don't know much about this sort of thing.
You don't know much about this sort of thing.
You don't know much about this sort of thing.
Yes. Or one flow and split just before the heat bank, or one flow and a
3-way diverter valve.
It wouldn't. Any so-called complexity is offset by greater efficiency.
The doesn't need to know the rad temps.
And far better giving greater efficiency and comfort conditions.
Explain you warped thoughts? Well er don't bother.
The compensator has a temp prob on the heat bank sylinder, raising the lowering the cylidmer temp to exactly is required reducing inefficient boiler cycling. This means a cheaper and simpler boiler can be bought.
Many condensing boilers, mainly the open vented heating type will maintain a set temperature.
You don't know much about this sort of thing.
You don't know much about this sort of thing.
This is exactly the kind of well reasoned, cohesive argument which has gained you a reputation for being a leading expert on the subject of domestic plumbing, and a superb communicator.
I know and they should, be run off the heat bank, directly if possible, as the heat bank is a neutral point, "not" off the boiler. All should be off the heat bank, with the boiler only heating the heat bank.
Exactly!! I tolerate know-it-all fools. When I write about heating and water systems take note, lots of note, you will benefit.
Whoops. Did I say boiler? I was thinking off the heatbank. In any case, having a multiple subzoned system off the boiler is easier implemented with zone valves in an S-Plan-Plus configuration (swapping the boiler for the heat bank as the heat source) than having, say, six takeoffs (each with pump) from the heat bank to supply each zone.
Christian.
P.S. It also requires less pipework in most cases, as a large bore unzoned main can snake around the house and the zoned takeoffs taken where convenient. Having the zoning done centrally can result in excessive pipework requirements, although it would allow microbore for those who prefer it.
Christian.
Of what?
The boiler will operate at its most efficient for heating purposes if it is directly connected to the heat emitters without the damping factor of a heatbank in the way.
The boiler?
It does if its best efficiency for heating is to be achieved.
Yes we know that.
There's no warp as far as I am concerned.
Do you know anything about control systems?
Here we go full circle.
Yes we know that boiler cycling is inefficient and to be avoided.
It is precisely what will happen if you connect a condensing boiler to a heatbank and then use the latter to supply the radiators. The temperature probe on the cylinder will provide information about the temperature of the cylinder. There is no way for it to know whether the heat use is for the DHW or for the radiators.
If you have the selection for DHW and CH before the heatbank such that either the radiators or the heatbank are connected, in the case of the radiators the boiler can modulate down based on the load and return temperature from them. It will tend to drop down to match the load and run at minimum temperature if possible - little or no cycling. When there is a demand for hot water, the heatbank will require a lot of heat, and for this the boiler can run at full blast, again without cycling.
What's the point? We know that they run more efficently at lower temperatures.
The characteristics of a heating circuit are markedly different to those for bulk energy storage at high temperatures.
Sigh.... .andy
To email, substitute .nospam with .gl
Only if a conventional boiler or other heating sources are used, not a modulating condensing boiler.
.andy
To email, substitute .nospam with .gl
I'd want to see further testing evidence for this, either way. I'm not convinced which is more efficient.
Basically, does the higher temperature burn required to reheat the heat bank outweigh the fact that the boiler gets to do occassional full power burns, rather than cycling, or modulating low.
Remember, that the heat bank might still be providing a reasonably low return temperature with a very high flow/return differential, which should offset some of the problems with regard to condensing.
Christian.
Pumps are simple, cheap and reliable. Even a DIYer can change one. Keep it simpe.
As far as you are concerned. Professionals would assess otherwise.
You are thick. I said you install a simple boiler and allow the controls to get the best out of the it.
The compensator lowers the return temperature. and you don't have an expensive complex boiler.
You don't know much about this sort of thing. A little knowledge is dangerous.
You don't know much about this sort of stuff.
You will not see any.
I have never come accross any.
They probaly do not allow Andy sharp objects.
The cycling was mainly on the eating and DHW if not a quick recovery coil.
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