[Solved] Heating with electricity, electrode boiler 15 kW galan & # 8211; opinion and

Hi

About half a year ago I was looking for information on electric heating and I was interested in the topic of electrode boilers, but I had a big problem with finding information on this subject - I have learned a lot since then, and now I would like to share my knowledge with you.

First, something about me.
A wooden log house, 11 years old and so far I have been heating with a gas stove + fireplace with a water exchanger installed at the outlet of the fireplace (it is something like a fireplace with a water jacket, but much less powerful). At the bottom, a floor covering at the top of the radiators.
I calculated myself using 2 methods that my heat demand is about 50 kWh / m2. One method is calculators from the Internet (I don't remember pages), and the other method is the average consumption of gas and wood, and calculation based on calorific value and consumption. The results were similar - about 50 kWh / m2. So on average.

At the beginning of this year, I set up a 6.6kW photovoltaic installation and decided to switch from gas to electric heating. I considered several options: a heat pump, an electric furnace, air conditioners, and as a result decided on a galan electrode boiler.

Installation costs. I have added an electrode boiler to the current system, which works in a separate system with an exchanger and heats only and only heating. , It combines the cost with the 3-phase installation, it amounted to almost PLN 3800 (own labor):
A boiler with a company controller from a galan with an ammeter - PLN 2153
Hydraulic items, fittings, etc. - PLN 800
Exchanger - 300 l
Cable, conduit, etc. - 210 liters
WiFi room controller - 217 PLN
Sub-count - ? 50
Pump controller - PLN 48
Distilled water - PLN 14

Electrode boiler. The most important information about this boiler is that the water in the system in which it works must be appropriate. That is, it must have appropriate conductivity (electrical conductivity) and the boiler power depends on it. And the second piece of information is that the power depends on the temperature of the medium. I was recommended to install this boiler in a separate system and I think it is a good idea.
The water I used was distilled water with the addition of baking soda - about 2g per 100l of water. For me, the water in the system is about 3 liters, so the amount of soda was minimal.
I set the mixture using an ammeter to reach the power of 15 kW. I've played it 3 times in total with varying degrees of success, and I have these observations:
At the beginning, I tried to set it to work with a power of 15kW. But I noticed that as the temperature rises, the power increases significantly. When I was doing a test of work without a pump, I started working with a power of almost 30 kW. It scared me a bit, so I finally set it to a much lower power.
Currently, at a temperature of about 20-22 degrees, it works with a power of 5kW. At a temperature of about 35-40 degrees 7-8 kW. And at a temperature of 70 degrees, the power is 12-13 kW. I did not check, but I suspect that for 80 degrees I will reach the nominal 15 kW.

Somewhere on the Internet I found negative descriptions for this boiler, that it is difficult to warm up the installation when it is cooled down. I confirm. If this stove is to be installed, for example, in a summer house, or in a room where the temperature will drop significantly, I advise against it. In my case, when I cooled the house to 18 degrees Celsius, I also had a problem with heating the installation - it kept the temperature up for a long time and finally I warmed up the installation with a gas stove, and then the electrode calmly continued ). How is it going nowI have a room thermostat, I don't cool the house anymore, the problem is no longer there ))

Boiler control. It works on an on and off basis. There is no power modulation. The power depends only on the quality of the heating medium (water). Theoretically, you can still think about switching off the phases - in my case, all 3 phases are going at once. I have no idea if it would be possible to somehow limit the power fed to the electrodes, probably yes, but I don't know anything about it.
The controller that is sold in the boiler works very well. The temperature and hysteresis are set there and the stove turns on and off very nicely, depending on the temperature in the system, but: the thermostat is very loud, it is not a soft pop, but a crack like a light hammer blow. Despite the fact that the stove is behind the door, you can hear these crackling noises. This is, in my opinion, the biggest drawback of this driver.
The second drawback is that the temperature is set manually. The controller changing the operating temperature cannot be connected, e.g. based on an external sensor.
Another thing I didn't like was the pump running non-stop. The controller does not turn it off when the temperature drops or when the stove is not working. I dealt with it in such a way that instead of the pump, I connected the controller to the pump, which turns it off when the temperature in the system drops below 30 degrees. And it works perfectly. But it's not a perfect solution - I'd prefer one integrated driver.
I connected a room controller with WiFi to the stove and it turns the stove on and off when needed and I can control it remotely - cost PLN 217 ))

Power consumption. My experience is short, less than 2 months and the temperature outside was not lower than around zero. I heat in such a way that the floor is not cold and the radiators are slightly warm. That's enough for now. In addition, I light the fireplace in the evenings and I have an average of 20kWh per day. Once, at the outside temperature of about 0, I left the stove on for 11h and when I came after work, it was 23 degrees and it was too warm. Then I used 70 kWh. I estimate that with such a temperature and no fireplace heating, I should use about 45-50 kWh per day. The consumption is about 2kW per hour and the water goes to the installation about 32 degrees. And that's enough for me.
When the outside temperature drops, it will surely use more electricity.

Ultimately, I planned to connect DHW heating in a 300l tank (this is a solar tank), but I could not find a controller that would set me a different temperature for heating the central heating and a different one for hot water. Currently, I can only manually set it, and because I have added an additional bypass behind the exchanger for the solar tank to the coil, I can manually heat up the DHW as an emergency option, if the gas stove fails. I even did a test, with 12 kW of power, the system worked at a temperature of 70 degrees from the furnace, and it did not even work non-stop, it reached the temperature and turned off. So the power of this boiler is enough to quickly heat up the domestic hot water in the tank )))

Why an electrode boiler and not a heat pump. As I wrote earlier, I set up a photovoltaic installation. If I kept the electricity consumption in winter for 6 months, for heating alone at about 20kWh per day, I would have heating for free ))... But I don't think it's possible. If I had a heat pump, it would definitely be enough. I counted that it would be cheaper to expand a photovoltaic installation than to install a pump. The end result will be the same - heating and electricity for free all year round ))

Finally, I will give the website https://ogoszeniaprademzadarmo.mojabudowa.pl/
I learned a lot on this website and forum. I recommend - a very nice and helpful guest )))

If anyone has any questions, I am here to help. I will add more information here over time.

Lodek wrote:

but I could not find a driver that would set a different temperature for me as central heating heating and a different temperature for hot water.

And mechanical mixing valves wouldn't solve the problem?

The second issue is whether the use of a tank with heaters would not be better than an electrode boiler?

There are Polish Kospel electric stoves that are great in operation and I know because I have one installed.
Why mix with heat pumps or such strange stoves?
You would buy an electric stove, e.g. 12kW, which adjusts the power itself depending on the temperature of the heating water, without complications, it is quiet because the heaters are heated by transistors.
My stove is already 14 years old, I bought it used and it is failure-free and most importantly it has security and a lot of it.
As for me, playing with such inventions as GALAN is just a waste of time and money and your post clearly shows what we are thanking for

A mechanical mixing valve would probably do the trick. But I don't like the idea of heating the water to high temperature just to be mixed right away.
I wanted to avoid heaters. Apparently, the electrode furnace is more efficient. But it is difficult to verify this information. Could use a comparative test. But I haven't found any

I was wondering about the Kospel stove, perhaps it would be a better option. Can you write something about electricity consumption? I am curious to compare

That season, while heating with heaters using a buffer, I used 7500kWh of heating + DHW.
Time from mid-October to the end of April on days where the outside temperature was> = 0C. Most of the time, that is. Heated area about 120m ^ 2. The internal temperature is 21C.

Added after 2 [minutes]:

Lodek wrote:

Somewhere on the Internet I found negative descriptions for this boiler, that it is difficult to heat up the installation when it is cooled down. I confirm. If this stove is to be installed, for example, in a summer house, or in a room where the temperature will drop significantly, I advise against it. For me, when I cooled down the house to a temperature of 18 degrees Celsius, I also had a problem with heating the installation - it took a long time to finish the temperature

So it cannot be used for G12 tariffs, so it disqualifies him.

House 130m2 Kospel 6kW stove - max consumption of the whole house in winter 75kWh in severe frosts.
Now I have a consumption of 50kWh.
Temperature at home 22.4stC during the day 22.2stC at night.

Lodek wrote:

I calculated myself using 2 methods that my heat demand is about 50 kWh / m2. One method is calculators from the Internet (I don't remember pages), and the other method is the average consumption of gas and wood, and calculation based on calorific value and consumption. The results were similar - about 50 kWh / m2. So on average.

What area of the house and what temperature inside did you count for?
What is your log diameter? What kind of insulation for the foundation and roof?

I heat 140m2 for PLN 12-15 / day. PPC.

kosmos99 wrote:

That season, while heating with heaters using a buffer, I used 7500kWh of heating + DHW.
Time from mid-October to the end of April on days where the outside temperature was> = 0C. Most of the time, that is. Heated area about 120m ^ 2. The internal temperature is 21C.

Mother, I would need to increase the power of the PV installation from the current 10kW to a minimum of 18 - 20kW to bring the heating and household electricity to zero. I was thinking about it, but first of all, I have a maximum of 15kW on the plot and the roof, so I hit PPC. For the next 10kW PV I would have to pay PLN 40k and for this amount I have a decent PPC for R32 and there is still money in my pocket and with electricity consumption I am about 20% above my current 10kW on the roof.

BikeBarian wrote:

For the next 10kW PV I would have to pay PLN 40k and for this amount I have a decent PPC

Only the PPC requires servicing, and the compressor will not last 25 years. So you have to take into account the costs that will be there later. And the panels, if mounted, 10kW for 25kPLN can be done.
Of course, if there is no place, it will not jump over it, but the installation does not have to cover 100%, the rest can be purchased in the night tariff.

And stop what servicing? Every 3 years, taking the lid off and seeing if the mice have eaten something, blow out the evaporator? 7kW pump with installation 23. Now, in 15 years, a hat of pears like a dryer. How 10 years ago I bought plasma for 3000, today I knock on my forehead

8KW Daikin Altherma 3 Hydrosplit on R32 for 23k with assembly. In addition, a surcharge from the commune 4k plus a thermo-modernization allowance and leaves 15K for everything (I do not have any allowances or subsidies for the upgrade of the PV installation). Nevertheless, I lean towards PPC.

andrzej20001 wrote:

stop what servicing? Every 3 years, taking the lid off and seeing if the mice have eaten something, blow out the evaporator?

Ooh, a refrigeration specialist has found. You probably haven't seen the JZ exchanger after the spring dusting of the plants. Not to climb about the dustiness of the air in cities and their surroundings.
Anyway, you need to do a lot of control activities to catch any faults on time and so that the device works with the design COP.
In addition, a device with a power above about 7kW and the R410a factor contains it so much that, in accordance with the current law, it should be reported to the CRO and be inspected at least once a year by authorized people.

There is no more than 7. The climate hangs for 10 years and it works and I did not go to the roof to see it. 3?

andrzej20001 wrote:

The air-conditioning hangs for 10 years and it works, and I did not go to the roof to see it.

Nothing to brag about ....
Unless you are lucky and the system is tight, or you have not noticed a drop in performance.
Wash the exchanger, you will see the color of the water flowing from it.

Brunoxp wrote:

Lodek wrote:

I calculated myself using 2 methods that my heat demand is about 50 kWh / m2. One method is calculators from the Internet (I don't remember pages), and the other method is the average consumption of gas and wood, and calculation based on calorific value and consumption. The results were similar - about 50 kWh / m2. So on average.

What area of the house and what temperature inside did you count for?
What is your log diameter? What kind of insulation for the foundation and roof?

One method of counting is counting the consumption of wood for the fireplace and the amount of gas burned. And 2 are online calculators for 21st
Bal 7 cm and 15 wool. Warming the foundation ttlko 5 cm - and it is not enough

Hello. I will join the discussion because I also have an electrode boiler. My situation is as follows ... a 9 kW boiler works with a heat buffer of 1000 l and heats it only in the 2nd tariff, an open system is connected with radiators and a floor. Everything works fine except for one incident ... I have to clean the electrodes every few days because they "grow" with something that is in the water throughout the entire system and therefore the boiler power drops. The system was flooded with hard water from the well because that's what I have. I thought this water was the cause of this problem so I set up a water treatment plant just to soften it. I changed all the water from the system to descaled and then another problem appeared ... namely the C20 circuit breaker started to throw out. As it turned out, the water has too high conductivity and the boiler consumes too much electricity. So I flooded the system with hard water from the well. He no longer throws away the overcurrent switch, but the first problem with the electrodes getting dirty remains. Anyone can advise something on how to solve this problem?

Hello
In my opinion, the water in which the stove works should be changed. Distilled water and baking soda would be perfect. Alternatively, you can use rainwater.
The galana manufacturer recommended rainwater.

Or to remake the installation and add an exchanger. It works for me. In the system with the stove, I have only 3l of water, so I used distilled water. I work 3 months without cleaning and treatment and I hope that I will pass the whole season and in the summer I will start the stove and see if it needs cleaning

I have coils in the buffer to connect an additional heat source, so probably a good solution will be to connect the furnace to it in a closed system and "select" water. Do I think right?

Exactly

Hello all.
Ladek tell me what exchanger do you have?
What size and power. For PLN 300, it's probably a small one

40 plate 35 kw 3/4 inch dn20

Hello
What is your pre-meter protection for a 15kw electrode furnace?
greetings

Minimum 25A

Hello
Lodek I read with curiosity about your activities in the matter of the electrode furnace, because a few days back I installed one in my boiler room. A 15 kW boiler connected to the 600 l accumulation tank coil, the system capacity is about 12 l, at a temperature of 65 degrees Celsius. C pulls about 13kW. Please write with what frequency your pump turns on and off, at what gear the circulation pump, what hysteresis. For me, for now, the phase of tests and combinations of settings, so this information would help me. I know for sure that my tap water is not suitable for flooding the system. After 20 hours of operation, it clogged the pump filter with red silt, the pump stopped "pushing", the temperature at the furnace outlet increased rapidly, so the power consumption was the same and the main protection (C25) was snapped and wiped clean. My power consumption has nothing to do with yours, but we'll see what happens when I load the entire buffer to 80st. C and even though I have a 10kWp photovoltaic installation, I can't see it well. In a few days I will finish the tests and modernization of the boiler room, I will be happy to share my observations and add some photos.
greetings

szpilazzio wrote:

even though I have a 10kWp photovoltaic installation, I can't see it well.

unfortunately, heating with COP = 1 with a PV installation misses the point ... unless your household electricity consumption for purposes other than heating is relatively small and the house is properly insulated.

BikeBarian wrote:

unfortunately, heating with COP = 1 with a PV installation misses the point

If there is room for the right number of panels and you do not mind the number of them, then the price will be better than the PC.

kosmos99 wrote:

BikeBarian wrote:

unfortunately, heating with COP = 1 with a PV installation is a bit pointless

If there is room for the right number of panels and you do not mind the number of them, then the price will be better than the PC.

Well, but only in well-insulated houses where the energy demand is low and it can be fully covered with PV. Then the simplicity of such a system is undoubtedly its big advantage.

Lodek thanks for the info.
Tell me how your heating turned out for last season.
You can take some photos with everything connected.
How the exchanger works for you. I was wondering about the heat buffer from 1000l. But if the exchanger is made, it probably makes no sense to buy such a large one.
I have a house of about 200 sq m. So a little bigger. But we'll see how it all works out.
So far, I am at the stage of ordering the furnace.

Hello. I have a 9kw galana for 3 seasons. So far without the buffer, but this year I added a 300l buffer with a coil for central heating, at the same time disconnecting the hot water. Frame house 110m?. Insulated with pressed wool 25 cm and 15 cm in the wall, 3-pane windows. So .. I turned on the buffer and hoped to go down to about 20-25kwh per day and at this time the use is 45-55kwh.
I have a tech-1cwu attached to the standard driver. There are 2 pumps - from the furnace to the buffer and then three-way and the pump to the floor heating. I have to sort things out that with drivers or someone will help, because since December 16 I have been sitting in the boiler room And my wife thinks that I have an affair ?
Lodek wrote that his g15kw uses less current at lower buffer temperatures. I have 6o?C, can it actually go down to 40-45?