Replacement of fine coal furnace with eco-pea coal furnace - extension of the in

Hello.
I am asking fellow installers for professional advice.
On the "drawing" below I have posted the current existing heating installation in the apartment.
The furnace that was used is a butterbur furnace.
Currently, an eco-pea coal furnace with a screw feeder is ordered.
Namely, I am talking about the modification of this installation to mount a mixing valve so that the water in the furnace at the return temperature is higher.
1. Where should the mixing valve be installed (definitely before the pump)?
2. Use a 3-, 4-way valve?
3. Where is the best place to install safety valves (currently one on the supply, the other on the return directly at the entrance to the furnace)?
4. I understand that the 4-way valve gives us the ability to control the radiator temperature and raise the temperature at the return of the furnace (whether I'm wrong
I mention that the installation is "closed" has a diaphragm tank.
I am asking for professional advice not to make an assembly error

Not enough data.
Describe exactly how the installation is made?
How thick are the pipes and from what material?
Does the installation have the ability to work in gravity (without the operation of the CH pump)?
Was the installation up to now of the open or closed type with an expansion vessel? The fine coal boiler in a closed system is mindless playing with life.
Do you have underfloor heating or radiators?
Do you already have a boiler selected, if so which one with which controller?
Is it possible for the boiler to have separate outputs for connecting the hot utility water tank (boiler)?
Does the boiler have an additional emergency grate and the possibility of burning wood or coal on the grate?
Are there thermostatic valves on the radiators?
Do you want to control the mixing valve by means of an actuator and a weather control?
Do you want to control the boiler operation using the room controller?

Do you have gas or the ability to connect it?
I am asking because now gas heating is comparable to eco-pea coal. I even get a little cheaper gas heating than eco-pea coal.

Unfortunately, many pseudohydraulics mindlessly connect 3D or 4D valves, spoiling the installation. Without answering the above questions, you can make many mistakes.

toshibanana wrote:

so as not to make a mounting mistake

The basic mistake is that the installation is closed. This must be an open installation and start from there.

First of all, thank you for your willingness to help.
Installation made in the 90's from copper.
28 kiln comes out of the stove, 28 'return (at the basement level)
power supply spreads at '22 and '18' and with 16 'radiators only


Does the installation have the ability to work in gravity (without the operation of the CH pump)?
- she always worked with the pump and controller but when there was no power at the bottom of the building the radiators were warm.

Was the installation up to now of the open or closed type with an expansion vessel?
- from the beginning it was a closed system

Do you have underfloor heating or radiators?
- heaters only

Do you already have a boiler selected, if so which one with which controller
25KW boiler Inter Electronics controller as in the picture

Is it possible for the boiler to have separate outputs for connecting the hot utility water tank (boiler)?
-The boiler has two supplies and two returns (as in the pictures)

Does the boiler have an additional emergency grate and the possibility of burning wood or coal on the grate?
- yes, it has an additional emergency grate

Are there thermostatic valves on the radiators?
- yes, there are heads

Do you want to control the mixing valve by means of an actuator and a weather control?
- I think it's enough manual

Do you want to control the boiler operation using the room controller?
-no

Do you have gas or the ability to connect it?
- if I had a "gas thread" I would certainly consider it, unfortunately I do not have it

The current installation consists of a pump on the supply, safety valves on the return and supply, a 2 coil boiler (one central, the other furnace with a horseshoe and a diaphragm tank).
The photo with the expansion tank is the current installation.
As for buddy jas67 then maybe I would have done the installation with the expansion tank but I have no way how to place it. The attic is usable and not too high (slants)



l

power connection 2 pieces

Return connection 2 pipes







I still have a question about connecting the boiler, namely leave this connection as it is now and plug one I / O or connect it to these additional connectors. I must admit that it seems to me that fewer adjustments would be made by blinding one of the crow's.
And is a gravity valve necessary?

Please assess this planned installation and any suggestions.



Thanks again for your help. Regards



Thanks again for your help. Regards

Let's start with the installation. Closed or open?
From a legal and common sense perspective, coal boilers can now be connected to closed installations if two conditions are met:
1. The boiler has the manufacturer's approval for operation in closed installations.
2. The installation will be equipped with a safety valve
3. The boiler will be equipped with a direct action cooler (operation without electricity) or a buffer, which is able to absorb energy from the entire charge of the boiler.

So as you can see the boiler must have 2 different protections and it is not about using two safety valves, only a safety valve + a second protection. The second protection is the easiest way to use a cooler.

When it comes to connecting the hot utility water tank it is best to connect it to the second set of connections (supply and return), thanks to which the system will be simplified and you will avoid certain problems. If the hot utility water tank is mounted above the boiler level, it doesn't even need a pump. It can work by gravity. This has its advantages and disadvantages. The advantages are a simple and cheaper connection, you can heat up hot water by burning on the grate in the absence of electricity. Disadvantages are that it will heat up a little more slowly and the temperature of the water in the tank will be the same as in the boiler.
But this temperature can be limited by installing a special thermostatic valve with a capillary that will limit the maximum DHW temperature. Too hot water in the tank causes faster wear of the tank, scaling. In return, you can be sure that there will be no legionella bacteria in the tray.

You ask about the gravity valve. You probably mean a differential valve?
Installation of such a valve makes sense only in systems that do not have mixing valves. The point is that the mixing valve deprives the installation of the ability to work more fully in gravity. In the case of a 3D valve, you can connect a differential valve so that in the event of a power outage or a failure of the CH pump, it will allow for gravitational work. But the disadvantage of 3D valves is that it can work in one of 2 configurations:
1. Lowering the water temperature in radiators, but then it does not fully protect the return temperature in the boiler.
2. Securing the water return temperature to the boiler, but then it does not lower the temperature in the radiator circuit, but only reduces and increases the circulation.

The 4D valve, on the other hand, lowers the temperature in the radiator circuit and increases the return temperature in the boiler, but such a valve prevents the installation of a differential valve, i.e. creating a gravity bypass. In one extreme position, the 4D valve cuts off the boiler from the radiator system, and in the other extreme position ensures operation as if there was no mixing valve and the whole can work in full gravity.

The selection, as you can see, is red:
3D valve - the option of installing a differential valve and gravitational operation after stopping the CH pump, working in one of the configurations (lowering the water temperature in the radiators or raising the boiler return temperature)
4D valve - it is not possible to mount a differential valve, but it is also possible to operate the system in full gravity after manually moving the 4D valve to one specific extreme position.

In the case of a boiler with a feeder, there are no problems with stopping the CH pump or power outage, because the boiler will simply stop heating. The problem is smoking on the grill. The person who operates such a boiler must remember that having a 4D valve must manually move it.
Becauseif the people who operate the boiler will be smart, install a 4D valve, but if it is a person who is scared of all technical matters, install a 3D valve + differential valve.

It is a pity that you already have this boiler and controller, because currently on the market there are much better boiler controllers that also control mixing valves and have built-in weather regulators. Such a weather regulator offers many benefits. First of all, it gives savings, and secondly it provides a more stable temperature at home and improves thermal comfort.
However, you can always add an additional weather control and actuator on the mixing valve.

There are also other solutions:
1. You can install a 3D valve in the configuration of reducing the temperature in radiators + differential valve, and raising the return temperature can be done with an additional mixing pump, which can also be used to charge the HUW tank.

2. Use a low loss header.

In both cases, 2 pumps will be needed.

Great respect buddy for comprehensive information!

Due to the fact that I am not always at home and people operating the stove during my absence are "older dates" the choice fell on a 3-way valve.

I found the option of pulling the thread into the expansion valve, and therefore I have a few questions.
Can you pull it "horizontally" around the basement by leveling about 3 meters and only vertically above the height of the last radiator?
This is the only way that I can convert into open circulation.

And what thickness would the pipes for this expansion tank have to have?

Is the sketch for this installation correct?


After reflection, it seems to me that a good solution for this reservoir would be to use the second of the exits ...

The drawing has several errors. Both technical errors and non-compliance with applicable law.
The riser pipe (the one that the expansion vessel is connected to) must not have a single valve in its path. The minimum diameter of this pipe in accordance with applicable law is a minimum of 25mm. So a 1 inch steel pipe or a 28mm copper pipe.
Installing a differential valve after the mixer is pointless.
This valve is intended to bypass both the pump and the 3D valve when the pump stops pumping.

I drew a revised installation sketch for my friend "Toshibanana". I ask more experienced people to check. In your drawing, the three-way valve is wrong because it will not protect the boiler return against too low temperature and you wrote that this is what you want to achieve, i.e. the pump must be before the three-way valve (the pump must pump some hot water to the return pipe). The differential valve and expansion vessel are bad. I would also improve the way pipes are laid next to the boiler. If I see correctly in the photo, the pipe on the boiler supply was partially air-sealed (the pipe has a slight slope in the wrong direction) and because of that the boiler could not heat 100%. Besides, I don't see the vent on this pipe. Enter the exact model of the boiler because it is not known if you need to connect the boiler to these additional outputs from the boiler.

Thank you for your response.
The furnace is such a "local product" with a capacity of 25KW. The manufacturer has two outputs to adapt the furnace assembly to the individual needs of the user (as the manufacturer said, you can also connect the boiler to it.
So I understand that just like a colleague kolys drew a pump in front of a 3-valve and a differential valve connected in parallel?
If possible, I would like to give up the pump I do not know if I will succeed and as a colleague wrote this boiler power supply I would like to pull in a straight line.
As for these vertical valves, they were installed by "specialists" so that you can heat the water in the boiler in the summer
Should the differential valve be larger than the pipe leaving the furnace reduced with muffs?
Regards

I suggest one of these two solutions:

Kocioł węg...chemat.jpg Download (179.73 kB)


or


Kocioł węg...emat 2.jpg Download (163.2 kB)

In my diagrams, the location directions (vertical, horizontal) of individual elements are very important.
I don't think I have to explain why and how?
If there are any doubts, I am waiting for the questions.

It should only be remembered that the diameter of the riser pipe (from the boiler to the expansion vessel) is a minimum of 25mm.

PS
By adding a second pump set in parallel to the differential valve at the HUW tank, this pump not only improves the loading of this tank, it also ensures mixing of water in the boiler, thanks to which the return temperature will be increased.
Of course, you can connect the radiator circuit and the DHW tank for a common return, and even use a shared power supply.
It would look like this:
Kocioł węg...emat 3.jpg Download (167.33 kB)

Is it so hard to insert a picture correctly?

What's the problem with the pictures?
You click on the image (thumbnail) and the enlargement will show up to full size.

Thank you for your help. The case has been resolved