A modern gas stove and an old installation with cast iron radiators.

as something above is my post about such an open circuit installation, currently 5 years without problems,
since the stove fired (junkers smart zsb22kW + tank, weather, controller), I do not smoke, only gas. I currently heat 160m2, the bill for January 2021 is PLN 500 (one of the highest in history, but January was quite cold), the temperature at home was around 22 on the ground floor, 20-20.5 in the bedrooms (too warm for me to sleep, but my wife ... ... you know). The heating is on practically all day from 6 to 23:30. The night setting is from what he remembers 19 degrees - if it fell, the stove will turn on but it does not happen, house in the 80s, terraced, insulated + windows 3 panes. The entire installation is old on cast iron. I do a stove inspection once a year. The stove is in the basement, the collecting vessel in the attic is about 10-11 m. My stove, complete with a chimney, controllers, sensors, tank + plumber, it was about 10,500. Now I can see that the stove itself with the tank can cost 9,000. I paid around 6000 for the stove / container / controls without a chimney and plumbing, so the prices went up sharply.

Thanks for the answers. What worries me the most is that, according to the law, I cannot put the boiler in the basement, because it is below ground level. Unless I don't know something.

jacek1296 wrote:

is below ground level.

Does natural gas also apply or only pb (LPG)?

The earthen does not stick to the cavities like propane - butane.

I do not know the natural gas, for me it is only propane-butane from the tank.

You obviously do not read with understanding. Insulate the pipes only where you do not want to heat. Each boiler with an of-on pressure sensor can be connected to an open system through an external pressure sensor. You are only a theorist, not a practitioner. You will never overheat the installation by installing a weather sensor.

I have no problems with condensing Chaffoteaux Inoa Green on an open 51-year-old installation for 3 years. Most of the cast iron only a few newer tin plates. In some places the pipes are more than 10cm in diameter. The water pressure is about 1 bar because the overflow vessel is about 11 meters above. Previously, it had worked for over 25 years on the old Gens. After the exchange, gas consumption decreased by approx. 50%. Last winter, this season was less than 3500. The house is about 350m. There will probably be more of these, because February was not so cold for a long time. In addition to the temperature sensor in the room, however, I added a timer which closes the contacts every 1.5 hours and turns on the boiler for about 25 minutes so that the radiators never cool down to a minimum. Unfortunately, it was getting unpleasantly cold next to the temperature sensor. Water temperature 52'C because with the higher pipe they knock unpleasantly. The temperature in the room ranges from 21 to 22'C.

You have 350 m2 of usable space and you pay PLN 3,500 for gas heating? This is an unbelievable result. This year I am replacing the old garbage with a Junkers Smart ceraput condensing boiler and the plumber wants to close the installations. The installation is old on cast iron and I have concerns if it will all work. The costs are high because I have to pull the gas home.

doxent wrote:

I have no problems with condensing Chaffoteaux Inoa Green on an open 51-year-old installation for 3 years. Most cast irons only have a few newer steel plates. In some places the pipes are more than 10cm in diameter. The water pressure is about 1 bar because the overflow vessel is about 11 meters above. Previously, it had worked for over 25 years on the old Gens. After the exchange, gas consumption decreased by approx. 50%.

Hello. A similar change awaits me with my grandparents, due to the rather poor appearance of the current AOGW-23.2-1-U Russian stove (39 years old, 21.5 ° C living room works well), corrosion of the exhaust outlet and difficult ignition). I am thinking of some budget / used condenser Vailant, which are quite a lot on the aftermarket, at a low price. The height of the overflow is similarly about 11m, pipes above the old 2 ", then 1.5". In front of (cast iron) radiators, 1 "pipes. I do not comment on these costs of 3500. I was surprised by the rigor of water pressure - do the Vaillants really fall off, or which would be recommended for such a treatment?

kolo9 wrote:

doxent wrote:

I have no problems with condensing Chaffoteaux Inoa Green on an open 51-year-old installation for 3 years. Most of the cast iron only a few newer tin plates. In some places the pipes are more than 10cm in diameter. The water pressure is about 1 bar because the overflow vessel is about 11 meters above. Previously, it had worked for over 25 years on the old Gens. After the exchange, gas consumption decreased by approx. 50%.

Hello. A similar change awaits me with my grandparents, due to the rather poor appearance of the current AOGW-23.2-1-U Russian stove (39 years old, 21.5 ° C living room works well), corrosion of the exhaust outlet and difficult ignition). I am thinking of some budget / used condenser Vailant, which are quite a lot on the aftermarket, at a low price. The height of the overflow is similarly about 11m, pipes above the old 2 ", then 1.5". In front of (cast iron) radiators, 1 "pipes. I do not comment on these costs of 3500. I was surprised by the rigor of water pressure - do the Vaillants really fall off, or which would be recommended for such a treatment?

. The description shows that the central heating installation is for gravity heating (the diameter of the twigs in front of the radiators is 1 ") - gravity requires large diameters. Of course, pump heating (with a circulation pump) will work.

So I have to understand that the pumps contained in condensing furnaces are enough? If so, which model is worth looking for (if only because of the reliability)

kolo9 wrote:

I am thinking of some budget / used condenser Vailant, which are quite a lot on the aftermarket, at a low price. The overflow height is similarly about 11m,

Buying used condensate is a financial suicide - of course that is my subjective opinion, if at all, as a spare parts resource.
The chimney will be important in your application, because the pressure of the water column (above 0.8 Bar) is enough to ignore the sensor. But the most important thing will be the quality of the boiler water, which you will not be able to provide without the exchanger.

zlotaronczka wrote:

Buying used condensate is a financial suicide - of course that is my subjective opinion, if at all, as a spare parts resource.
The chimney will be important in your application, because the pressure of the water column (above 0.8 Bar) is enough to ignore the sensor. But the most important thing will be the quality of the boiler water, which you will not be able to provide without the exchanger.

Very valuable comments - thanks. I thought that a nicely maintained 8-year-old Vailland would be able to work for many years (like this Russian). I watched photos of interiors of several models together with my grandfather and they made us very optimistic. What makes "suicide"? What is critical in them? Perhaps if instructed, I will be able to judge it. I am simply motivated by the safety of my grandparents and the current state of affairs, unfortunately taking into account a small amount of money. That is why every professional note is a treasure. Water - do you think about purity?
On the other hand, the chimney is now almost 12 meters with a pipe made of acid iron. The current capacity is about 150-190l (according to my grandparents' testimony). Next to the gas boiler there is a reserve coal (cut off with 2 "valves)

kolo9 wrote:

I thought that a nicely maintained 8-year-old Vailland would be able to work for many years (like this Russian).

I have a bad feeling about this. Someone will install or yourself with the help of Google?
A small cash is what amount?
A chimney of this length may be a problem, with older models, with three knees - it will be a problem.
A chimney of this length will condense all the fumes - if it is the one on which the coal was buried - after the first season it will be a problem.
How to evaluate?
What is this model - two or three letters followed by three numbers and letters, for example VUW246
First of all: negotiate some kind of guarantee that the boiler will start at least 24 hours a day. Without it, you can buy scrap at PLN 1.20 per kg.
Secondly, if it is actually condensate, you would have to disassemble the burner to check if the flue gas / water exchanger is overheated - purple color on the lamellas (this is the most common cause of boiler death)
If you have no experience, such a purchase will be a Russian roulette with a loaded shotgun.

Thanks, the performers are me and my grandfather. If not this summer, then the next. We saw stoves from OLX in our area. We did not buy one because there were ugly interference or sloppy wear visible. But new ones appear all the time, so he goes to buy knowing "what to look for". Grandfather assembled the entire current installation, which has been operating with a Russian stove for 40 years. He knows gas, but he doesn't know new stoves. He repairs all household appliances in the family, he was a mechanic, he turned, milled, welded. He assembled the first furnace in this installation by himself, based on the PG6 furnace design. Beautiful work, with all security features, fine turned threads. Lots of brass. Later, he set up this Russian with worse efficiency, but with a certificate, because there were inspections. The controller bought the old structure for a plot of land. Grandfather - retired for several years, due to leg contusion.
However, he wants to Vaillant because "there are a lot of them, so I guess there are parts". He is in no rush, because so far the Ruthenian is working. It is important that you direct us to the model that is worth looking for . Condensate is not an obligation, I will accept any rational advice.

kolo9 wrote:

he feels like "there are a lot of them, so I guess there are parts". He is in no rush, because so far the Ruthenian is working.

This changes things - start collecting funds. You'll get something by summer. If your grandfather is such a handyman, he probably has a lot of "advances" in the purchase of non-ferrous metals that will also contribute to the fund.

But seriously - I will ask again: what amount ??

Without a budget, nothing can be done here.
The cost of the chimney will be higher than the boiler used. Check the possibility of exhaust gas ejection through the wall.

There is a half-basement of the "adjoining" facilities, but there is a lot of pressure on my part for something typical, safe. I don't know what you advise. In casual talks, the amount was about 5,000. Demonstration stoves on the forums a lot, from 100-500. The old installation did not have DHW because the central heating riser is far from the bathroom and the same from the kitchen. Flow heaters are installed there. The coal flue gas stack next to it is closed / ventilation.

Andrzej - the chimney, as I wrote, IS, brick, with an inserted acid tube, about 12.5 m, to the present Russian stove. The exhaust gases from Russia are also effectively released today. If sometimes there is condensation and single drops run off - this is the drain to the suspended container. Personally, I have never noticed it, except for some dried-up marks on the bottom of the container. Do you suggest this ejection through the wall for the purpose of better operation of the condensate? If so, it can give up this version in favor of an older or "different" version? Sorry for lamerism, but this is not my industry. In fact, heating the chimney wall in the center of the building is also my warmth.

kolo9 wrote:

There is a half-basement of the "adjoining" facilities, but there is a lot of pressure on my part for something typical, safe. I don't know what you advise. There was an amount of around 5,000 in casual conversations.

If you have not mistaken the number of zeros in the above amount - new boiler.
Convince your grandfather and other decision-makers that makeshift purchases are total stupidity!

kolo9 wrote:

Andrzej - the chimney, as I wrote, IS, brick, with an inserted acid tube, about 12.5 m, to the present Russian stove. The exhaust gases from Russia are also effectively released today. If sometimes there is condensation and single drops run off - this is the drain to the suspended container. Personally, I have never noticed it, except for some dried-up marks on the bottom of the container. Do you suggest this ejection through the wall for the purpose of better operation of the condensate? If so, it can give up this version in favor of an older or "different" version? Sorry for lamerism, but this is not my industry. In fact, heating the chimney wall in the center of the building is also my warmth.

Therefore, it is enough to buy an internal flue gas duct ? 60 or 80, a chimney cap, and try to reduce the external air intake duct.

zlotaronczka wrote:

- new boiler.

which? - write openly which would make sense under these conditions Grandpa I know that he will just repair the old one and leave it, but I want changes.

kolo9 wrote:

zlotaronczka wrote:

- new boiler.

which? - write openly which would make sense under these conditions Grandpa I know that he will just repair the old one and leave it, but I want changes.

Termet Silver is the reasonably priced, manufactured in-house heat exchanger coiled from one tube, easy access to consumables and spare parts. The single-function boiler is produced in the powers of 20, 25, 35 kW.
How much usable space do you heat?

I do not want to repeat myself once again what has already been written by wise people, so for starters:
https://www.elektroda.pl/rtvforum/topic3508453.html
If you have some oil in your head, you can look for it, read it and draw conclusions yourself.
If you need to specify something - write.
However, if you want a beautiful cauldron with a beautiful display and other goodies, buy these inventions.
ACV Kompakt or Thermagen are old, proven and solid constructions.
Of course, they are not "trendy" (recently one of the users was "outraged" that the link to the topic I gave is 4 years old) because they do not have a beautiful display and other wonders but the question is what do you expect.

zlotaronczka wrote:

How much usable space do you heat?

about 120m2. Thanks for the many specific comments and suggestions, that's what I need. Termets are undoubtedly interesting and I look in their direction once again, so far the price has been a bit scared off.

Prof. SpecMiernik wrote:

However, if you want a beautiful cauldron with a beautiful display and other goodies, buy these inventions.

-this I avoid, I am interested in the ease of adaptation to my conditions, ease of use, price and longevity. It is designed to be hassle-free for grandparents.

kolo9 wrote:

Termets are undoubtedly interesting and I look in their direction once again, so far the price has been a bit scared off.

3.5 thousand for a new condensing boiler ????

kolo9 wrote:

Termets are undoubtedly interesting and I look in their direction once again, so far the price has been a bit scared off

Oh well. It is true that compared to scrap bucks, it's a lot of money, even the Himalayas.
And that's not the end of expenses. Good news: you should stay in the 5000 PLN.

The approach of grandparents (especially of a practical grandmother) is very "specific". She has long stated that when grandfather dies, she has to stay with a simple, effective and safe structure. No frills, because they will scare her when in 3 months she forgets what they were used for in the previous season. The third time I read the link of the Meter, so as not to miss any arguments. The work is still far away, but I am absorbing your suggestions and thank you for them. Grandma even started asking about the ground heat pump (cooperating with the modernized boiler room, "because my cousin in Kutno wants to do it" ) I suspect they don't want to talk to me about the budget, but I liked my grandmother's sentence "instead of your monument, I prefer a decent installation of yours, quoted by your grandfather - thank you for Valentine's Day". I will gladly be "physical" and collect your prompts. Okay, enough sweetening. What to do with this chimney, what should it look like using what is?

kolo9 wrote:

The third time I read the link of the Meter, so as not to miss any arguments.

I don't know what "not to miss any arguments" means, but read on:
https://www.elektroda.pl/rtvforum/topic3310324.html
ACV Kompakt / Thermagen boilers may not have great marketing and advertising, but it is a proven design from the 70s / 80s (if I remember correctly )

kolo9 wrote:

o to do with this chimney, what should it look like using what is?

First, decide if you want to buy a new boiler or scrap.
You have given a fairly large height of the chimney - it is at the limit of its efficiency. Exact value is needed - to decide how to bite the problem.
When deciding which company the boiler should be, take into account the availability of the service - it is best to contact us before the final purchase, ask for a visit in order to avoid problems with obtaining the approval needed for the warranty.