ᐅ New gas heating system with natural gas connection directly to the house, gas boiler
Created on: 9 Sep 2013 18:26
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daniel-frieseD
daniel-friese9 Sep 2013 18:26Hello,
First of all, a big compliment for this forum, it’s really great.
Now to my concern:
My partner and I have recently purchased a house that we can start renovating next week. The house was built in 1959 and has a natural gas connection directly to the building. Currently, there is a gas boiler from the 1970s installed, which I want to replace with a gas combination boiler. This means installing radiators in every room and, of course, providing hot water through the boiler as well. I have already received a quote from a company that would sell and install the boiler for 3000 euros. So far, no problem. However, our budget is limited, so I might do a lot of the work myself. I don’t know what type of gas pipes I should use. How deep do I need to chase the channels in the walls? What else should I be aware of? I plan to meet with a professional next week to discuss how they envisage the installation. Unfortunately, I’m not experienced in this field and would like to learn more beforehand so I can familiarize myself with the whole process.
I would be very grateful for any advice.
Best regards,
Daniel
First of all, a big compliment for this forum, it’s really great.
Now to my concern:
My partner and I have recently purchased a house that we can start renovating next week. The house was built in 1959 and has a natural gas connection directly to the building. Currently, there is a gas boiler from the 1970s installed, which I want to replace with a gas combination boiler. This means installing radiators in every room and, of course, providing hot water through the boiler as well. I have already received a quote from a company that would sell and install the boiler for 3000 euros. So far, no problem. However, our budget is limited, so I might do a lot of the work myself. I don’t know what type of gas pipes I should use. How deep do I need to chase the channels in the walls? What else should I be aware of? I plan to meet with a professional next week to discuss how they envisage the installation. Unfortunately, I’m not experienced in this field and would like to learn more beforehand so I can familiarize myself with the whole process.
I would be very grateful for any advice.
Best regards,
Daniel
A
AallRounder10 Sep 2013 08:57Hello Daniel,
Basically, it is possible for a layperson to install a heating system. I have now installed two complete gas heating systems including the boiler, and one system with just the heating circuits, all as DIY projects. The only absolute no-go is the gas line—no layperson should attempt that.
In my opinion, you need a certain basic knowledge, which can be acquired through years of dedicated learning from books, specialist forums and articles online, and countless conversations with heating and plumbing professionals. You should be confident in soft soldering and flaring techniques and have plenty of patience and perseverance. I have been a DIY builder for almost 20 years now, including heating and plumbing work. My systems are still running smoothly without problems. You save a lot of money but must invest a lot of time, effort, interest, and initiative. Heating engineering is, like any other skilled trade, a recognized vocational profession. As a layperson, you will always just scratch the surface and gain basic knowledge—you will never become a true heating engineer.
For my self-built heating systems, I have taken the following routes:
1. Building with a "kit" and a "self-build company”
Ultimately, this option is just an overpriced material sale. These companies promise you plenty of support and claim that you can relax in the summer. Once the materials have been delivered to your site in one shipment and your hard-earned money has been paid, contact with the company effectively ends. You receive a stick-figure drawing for the piping, which a five-year-old could have drawn better, and you only hear from your clever "energy consultant" again if you threaten legal action or similar. But that doesn't help either since the "energy consultant" usually only knows how to spell "energy" and has no real knowledge of heating systems. Eventually, you get the generous offer that a contractor—who happens to work with the self-build company—will complete soldering your mess, naturally at a completely inflated price. They know that no outsider would want to take it on, and thus have a monopoly on pricing.
This is the point where you decide whether you push through or whether your self-built heating system ends up costing more than a system installed by a professional from the start. I decided to push through and essentially learned a life lesson. I will never forget that steep learning curve. After six months of working on the heating system in every free moment, the small system was operational. The inspector from the company said it was the first self-build heating system he had approved that was genuinely self-built. The others were typically installed either by the buyers’ own professional tradespeople or by the self-build company’s contractors—that’s how the industry works.
2. Building with a patient master craftsman who doesn’t get upset if someone else is a dilettante in his field
I was lucky enough to meet such a person. We spent entire evenings talking about heating systems. It was an exciting time. The man wanted to pass the company on to his son, who wasn’t interested. Then I came along as a young person and got his lessons, which I eagerly absorbed. My DIY experience was a small foundation to build on. I could already flare and soft solder up to 28mm (1 inch) copper pipes neatly. I installed this system entirely by myself as well. I just had all materials delivered at wholesale prices, borrowed a pressing tool because I really wanted to try it out, and got started. The boiler was a simple model with a wall template and a well-documented connection diagram, so it was straightforward. I built a domestic hot water circuit with a separate electric instantaneous water heater because electricity was still affordable then. My house was too small for a storage tank.
Whenever I had questions, I could call the master craftsman, and he helped immediately. If parts were missing, he arranged them for me through wholesale channels. I saw him again only once on site for the gas connection and commissioning.
3. Self-building the heating circuits with boiler and storage tank connection done by a company
I took this approach for my third system. It took me a year to find a company that understood they wouldn’t be liable if something went wrong with my heating circuits. Of course, other issues come into play: the company doesn’t earn much from such a job and fears disputes if problems occur ("if it doesn’t get warm") about the cause (boiler or heating circuit). Ultimately, I still don’t understand the hesitation toward this option because companies also carry out boiler replacements, connecting new central units to existing circuits. Maybe you’ll find a company more quickly for such a project.
Since I had over 600 meters (1,970 feet) of pipe to install and 20 cast iron radiators to refurbish and hang, I spent about three quarters of a year just on the heating circuit. The contractor who installed the gas line, boiler, and storage tank carefully checked my piping and slowly commissioned the relatively large system. He was appalled by the radiators and said he never wanted to do that again. He was from the old school and knew the effort involved. The advantage here is that you can buy all the materials from (reputable) online suppliers and have them delivered free at prices no local wholesaler could match if they hope to make a living.
So, now you know three options and can choose one! What they all have in common is that they require a lot of work and time, and you may have to accept setbacks. Theory is also necessary; otherwise, you risk building in mistakes that are hard to fix. You must be able to understand and question the statements and proposals of professional companies. Is that worth €3,000 to you?
To conclude, a brief and specific answer to your questions:
Pure underfloor heating doesn’t seem to be an option for you, so I’ll focus only on radiators:
Piping
You must not install gas pipes yourself, as mentioned above. I assume you mean heating pipes. Modern systems always have two: the supply line (usually marked red) and the return line (marked blue)—one pipe carries hot water away from the heat source, and one returns cooler water. The heat generator includes a circulation pump that keeps the system running. Hydraulics alone no longer provide circulation these days. Those were the old gravity heating systems with huge pipe diameters. No one installs those anymore, and as far as I know, there are no heat generators for such systems. The downside is that you cannot heat during a power outage.
In new buildings or renovations where the floors are replaced, heating pipes are often embedded in the floor. This is the easiest method labor-wise. For this, you need panel radiators with so-called valve blocks or foot valves, allowing the supply and return to connect at the bottom because both pipes come out of the floor. However, the classic installation is surface-mounted, meaning the pipes run visibly along the skirting boards and as risers in room corners. There are also systems where pipes disappear behind the skirting boards. It’s a matter of personal preference. But always keep in mind that the pipes inside the rooms also emit heat. If you fix, hide, or obstruct them, you get heat buildup in useless places instead of radiating warmth into the space. Pipes are generally not embedded in walls because that would cause a lot of heat there, potentially damaging plaster and wallpaper. Usually, only risers and manifolds are hidden in proper installation shafts where the pipes can also be sufficiently insulated to avoid heating up the shaft.
Regarding your question about materials, I see only two viable answers: either classic copper or modern plastic pipes—specifically high-quality, almost oxygen-tight multilayer composite pipes. The latter is the most common solution for underfloor heating and screed installations. Some craftsmen, however, still use copper-flex pipes with sleeves in floors, arguing that plastic pipes must be replaced after about 20 years anyway. But this is by far the most expensive solution nowadays.
Pipe layout should always support natural hydraulics. This becomes more important the more floors you need to supply, the greater the height differences, and the volume of water involved. That determines the number of risers, branch lines, and the corresponding pipe diameters. If designed incorrectly or undersized, even a powerful heat generator won’t deliver adequate heat. My system holds nearly 1,000 liters (265 gallons) of water, has three floors and 20 cast iron radiators—each radiator is connected to a 28mm (1 inch) riser. I reduce that to 22mm (7/8 inch) and use short branches. Despite the often-criticized inertia of this old technology, it heats up quickly this way. The radiators are hot and radiate a lot within 20 minutes—even at minus 20°C (−4°F). If you install only standard panel radiators of average hardware store quality, which typically rust through after a few years, you can use smaller diameters and fewer risers. But I would question a pure "horizontal heating" system, where supply and return pipes run only once across all floors. In my opinion, that is acceptable only if the upper floors have just a few square meters to heat.
Radiators
Besides the mass-market panel radiators, you can still buy cast iron radiators new, but they are usually very expensive. Alternatively, you can get them secondhand quite easily since they are often discarded during renovations. Cast iron radiators are considered to provide more comfortable warmth because they emit much more radiant heat than panel radiators, which rely more on air convection—cold air falls into the gaps between the panels, warms up, and then rises. Underfloor heating is even more extreme in this regard, continuously circulating and stirring up dust from the entire floor—an allergy nightmare. The advantage of panel radiators is fast warm-up because they contain little water. They also cool down quickly. This contradicts the condensing technology principle of continuous modulation: the burner operates steadily but adjusts its power according to heat demand. Turning radiators off completely and then back on costs more energy than running at a low constant level. Cast iron radiators handle this better because they contain more water and store heat due to the iron mass. Panel radiators are mostly made of cheap sheet metal. You might get recommended higher quality options.
Alternatively, there are also wall or baseboard heating systems, but those are probably not economically interesting for you.
Heat generator / Domestic hot water
Nowadays, condensing technology is mostly installed. Its main advantage, in my opinion, is modulation (as mentioned above). But incorrectly installed or sized systems tend to "short cycle," meaning instead of modulating, the burner frequently switches on and off, which wears it out quickly and increases gas consumption. Short cycling is a complex topic that could fill books.
The distinction between boiler and water heater is usually based on water content and material: a boiler holds a lot of water and is made of cast iron; water heaters contain little water and are made of sheet metal. There are high-quality water heaters from reputable manufacturers that are on par in performance and reliability with boilers. So-called combination boilers also handle domestic hot water: through a priority principle, the unit runs at full power when hot water is demanded and heats a small volume of water in a flow-through process. During that time, no space heating occurs. If mis-sized, you may need two hours to fill a bathtub or end up with a trickling shower that only delivers lukewarm water to your disappointed face. This is, from my experience, a very sensitive issue. The highest comfort is achieved with a separate storage tank. The downside is that hot water is produced in advance and must be kept warm continuously if not fully used. There are no loss-free tanks, but you can limit losses through sensible tank sizing (not too small, not too large) and various settings. Usually, you need a separate pump for the hot water circuit, though there are also single-pump systems. You can also consider a circulation system so that hot water reaches the tap immediately when turned on (in simple terms).
Those were some thoughts to get you started.
Best regards,
AallRounder
Basically, it is possible for a layperson to install a heating system. I have now installed two complete gas heating systems including the boiler, and one system with just the heating circuits, all as DIY projects. The only absolute no-go is the gas line—no layperson should attempt that.
In my opinion, you need a certain basic knowledge, which can be acquired through years of dedicated learning from books, specialist forums and articles online, and countless conversations with heating and plumbing professionals. You should be confident in soft soldering and flaring techniques and have plenty of patience and perseverance. I have been a DIY builder for almost 20 years now, including heating and plumbing work. My systems are still running smoothly without problems. You save a lot of money but must invest a lot of time, effort, interest, and initiative. Heating engineering is, like any other skilled trade, a recognized vocational profession. As a layperson, you will always just scratch the surface and gain basic knowledge—you will never become a true heating engineer.
For my self-built heating systems, I have taken the following routes:
1. Building with a "kit" and a "self-build company”
Ultimately, this option is just an overpriced material sale. These companies promise you plenty of support and claim that you can relax in the summer. Once the materials have been delivered to your site in one shipment and your hard-earned money has been paid, contact with the company effectively ends. You receive a stick-figure drawing for the piping, which a five-year-old could have drawn better, and you only hear from your clever "energy consultant" again if you threaten legal action or similar. But that doesn't help either since the "energy consultant" usually only knows how to spell "energy" and has no real knowledge of heating systems. Eventually, you get the generous offer that a contractor—who happens to work with the self-build company—will complete soldering your mess, naturally at a completely inflated price. They know that no outsider would want to take it on, and thus have a monopoly on pricing.
This is the point where you decide whether you push through or whether your self-built heating system ends up costing more than a system installed by a professional from the start. I decided to push through and essentially learned a life lesson. I will never forget that steep learning curve. After six months of working on the heating system in every free moment, the small system was operational. The inspector from the company said it was the first self-build heating system he had approved that was genuinely self-built. The others were typically installed either by the buyers’ own professional tradespeople or by the self-build company’s contractors—that’s how the industry works.
2. Building with a patient master craftsman who doesn’t get upset if someone else is a dilettante in his field
I was lucky enough to meet such a person. We spent entire evenings talking about heating systems. It was an exciting time. The man wanted to pass the company on to his son, who wasn’t interested. Then I came along as a young person and got his lessons, which I eagerly absorbed. My DIY experience was a small foundation to build on. I could already flare and soft solder up to 28mm (1 inch) copper pipes neatly. I installed this system entirely by myself as well. I just had all materials delivered at wholesale prices, borrowed a pressing tool because I really wanted to try it out, and got started. The boiler was a simple model with a wall template and a well-documented connection diagram, so it was straightforward. I built a domestic hot water circuit with a separate electric instantaneous water heater because electricity was still affordable then. My house was too small for a storage tank.
Whenever I had questions, I could call the master craftsman, and he helped immediately. If parts were missing, he arranged them for me through wholesale channels. I saw him again only once on site for the gas connection and commissioning.
3. Self-building the heating circuits with boiler and storage tank connection done by a company
I took this approach for my third system. It took me a year to find a company that understood they wouldn’t be liable if something went wrong with my heating circuits. Of course, other issues come into play: the company doesn’t earn much from such a job and fears disputes if problems occur ("if it doesn’t get warm") about the cause (boiler or heating circuit). Ultimately, I still don’t understand the hesitation toward this option because companies also carry out boiler replacements, connecting new central units to existing circuits. Maybe you’ll find a company more quickly for such a project.
Since I had over 600 meters (1,970 feet) of pipe to install and 20 cast iron radiators to refurbish and hang, I spent about three quarters of a year just on the heating circuit. The contractor who installed the gas line, boiler, and storage tank carefully checked my piping and slowly commissioned the relatively large system. He was appalled by the radiators and said he never wanted to do that again. He was from the old school and knew the effort involved. The advantage here is that you can buy all the materials from (reputable) online suppliers and have them delivered free at prices no local wholesaler could match if they hope to make a living.
So, now you know three options and can choose one! What they all have in common is that they require a lot of work and time, and you may have to accept setbacks. Theory is also necessary; otherwise, you risk building in mistakes that are hard to fix. You must be able to understand and question the statements and proposals of professional companies. Is that worth €3,000 to you?
To conclude, a brief and specific answer to your questions:
Pure underfloor heating doesn’t seem to be an option for you, so I’ll focus only on radiators:
Piping
You must not install gas pipes yourself, as mentioned above. I assume you mean heating pipes. Modern systems always have two: the supply line (usually marked red) and the return line (marked blue)—one pipe carries hot water away from the heat source, and one returns cooler water. The heat generator includes a circulation pump that keeps the system running. Hydraulics alone no longer provide circulation these days. Those were the old gravity heating systems with huge pipe diameters. No one installs those anymore, and as far as I know, there are no heat generators for such systems. The downside is that you cannot heat during a power outage.
In new buildings or renovations where the floors are replaced, heating pipes are often embedded in the floor. This is the easiest method labor-wise. For this, you need panel radiators with so-called valve blocks or foot valves, allowing the supply and return to connect at the bottom because both pipes come out of the floor. However, the classic installation is surface-mounted, meaning the pipes run visibly along the skirting boards and as risers in room corners. There are also systems where pipes disappear behind the skirting boards. It’s a matter of personal preference. But always keep in mind that the pipes inside the rooms also emit heat. If you fix, hide, or obstruct them, you get heat buildup in useless places instead of radiating warmth into the space. Pipes are generally not embedded in walls because that would cause a lot of heat there, potentially damaging plaster and wallpaper. Usually, only risers and manifolds are hidden in proper installation shafts where the pipes can also be sufficiently insulated to avoid heating up the shaft.
Regarding your question about materials, I see only two viable answers: either classic copper or modern plastic pipes—specifically high-quality, almost oxygen-tight multilayer composite pipes. The latter is the most common solution for underfloor heating and screed installations. Some craftsmen, however, still use copper-flex pipes with sleeves in floors, arguing that plastic pipes must be replaced after about 20 years anyway. But this is by far the most expensive solution nowadays.
Pipe layout should always support natural hydraulics. This becomes more important the more floors you need to supply, the greater the height differences, and the volume of water involved. That determines the number of risers, branch lines, and the corresponding pipe diameters. If designed incorrectly or undersized, even a powerful heat generator won’t deliver adequate heat. My system holds nearly 1,000 liters (265 gallons) of water, has three floors and 20 cast iron radiators—each radiator is connected to a 28mm (1 inch) riser. I reduce that to 22mm (7/8 inch) and use short branches. Despite the often-criticized inertia of this old technology, it heats up quickly this way. The radiators are hot and radiate a lot within 20 minutes—even at minus 20°C (−4°F). If you install only standard panel radiators of average hardware store quality, which typically rust through after a few years, you can use smaller diameters and fewer risers. But I would question a pure "horizontal heating" system, where supply and return pipes run only once across all floors. In my opinion, that is acceptable only if the upper floors have just a few square meters to heat.
Radiators
Besides the mass-market panel radiators, you can still buy cast iron radiators new, but they are usually very expensive. Alternatively, you can get them secondhand quite easily since they are often discarded during renovations. Cast iron radiators are considered to provide more comfortable warmth because they emit much more radiant heat than panel radiators, which rely more on air convection—cold air falls into the gaps between the panels, warms up, and then rises. Underfloor heating is even more extreme in this regard, continuously circulating and stirring up dust from the entire floor—an allergy nightmare. The advantage of panel radiators is fast warm-up because they contain little water. They also cool down quickly. This contradicts the condensing technology principle of continuous modulation: the burner operates steadily but adjusts its power according to heat demand. Turning radiators off completely and then back on costs more energy than running at a low constant level. Cast iron radiators handle this better because they contain more water and store heat due to the iron mass. Panel radiators are mostly made of cheap sheet metal. You might get recommended higher quality options.
Alternatively, there are also wall or baseboard heating systems, but those are probably not economically interesting for you.
Heat generator / Domestic hot water
Nowadays, condensing technology is mostly installed. Its main advantage, in my opinion, is modulation (as mentioned above). But incorrectly installed or sized systems tend to "short cycle," meaning instead of modulating, the burner frequently switches on and off, which wears it out quickly and increases gas consumption. Short cycling is a complex topic that could fill books.
The distinction between boiler and water heater is usually based on water content and material: a boiler holds a lot of water and is made of cast iron; water heaters contain little water and are made of sheet metal. There are high-quality water heaters from reputable manufacturers that are on par in performance and reliability with boilers. So-called combination boilers also handle domestic hot water: through a priority principle, the unit runs at full power when hot water is demanded and heats a small volume of water in a flow-through process. During that time, no space heating occurs. If mis-sized, you may need two hours to fill a bathtub or end up with a trickling shower that only delivers lukewarm water to your disappointed face. This is, from my experience, a very sensitive issue. The highest comfort is achieved with a separate storage tank. The downside is that hot water is produced in advance and must be kept warm continuously if not fully used. There are no loss-free tanks, but you can limit losses through sensible tank sizing (not too small, not too large) and various settings. Usually, you need a separate pump for the hot water circuit, though there are also single-pump systems. You can also consider a circulation system so that hot water reaches the tap immediately when turned on (in simple terms).
Those were some thoughts to get you started.
Best regards,
AallRounder
As a non-professional laying a gas line... you have to give yourself credit for courage. But as already mentioned, you are not allowed to do that.
We have a gas cooktop that the kitchen installer was not allowed to connect. I wouldn’t have been allowed to either. I had to call a professional who connected the hose at the bottom using a quick-connect fitting and tightened a nut on top. It took about 10 minutes, but he also checked for leaks. And he takes responsibility if anything happens.
We have a gas cooktop that the kitchen installer was not allowed to connect. I wouldn’t have been allowed to either. I had to call a professional who connected the hose at the bottom using a quick-connect fitting and tightened a nut on top. It took about 10 minutes, but he also checked for leaks. And he takes responsibility if anything happens.
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