How to heat a home with an open fireplace: Adding a cupper coil, by Rafa

Fireplace coil made of copper by Rafael, with added doors

The people are so rigged. Rafa, a Seville plumber of 52 years, residing in Gerona has been kind enough to share with us their system , very similar to mine , which  for heating radiators leverages the built-in fireplace (yes, those that turn you on ahead and I grow cold by behind), achieving a more than worthy result to save wood and heat the house. 
He was not aware of these pots (used in villages of the Basque Country for decades), and their parents save money and gave googled my page, went looking for and found Lacunza, in whose  assembly schemes relied for connecting pumps, thermostats , etc., which sells kits pumps and thermostats ready for its chimneys, and the coil was based on the they have for sale Fireplaces Sierra , but made ​​with 15 mts. welded copper tin / silver . Detail thermometer, thermostat at 45 ° C to activate pumps and sensor of the safety valve 90 (not visible in the picture, touching the tube) which triggers a valve that ejects the last water this temperature outside and in turn enter cold water from a faucet automatic filling (in another photo) set to 1.5 bar:

Detail shot regulating door, right thermostat, thermometer and safety valve sensor

It is an old poorly insulated house , place insulation is complicated because you can just put insulation (expanded polystyrene) in the attic; the walls are exterior with large windows overlooking the side adjoining houses, which has many losses; spends up to 4 tons of wood every 2 months.

With the installation has managed to save at least € 150 every two months in wood, plus better heat the house, now pays € 400 every two months, before coming to pay 600 € monthly gas. Installation details

Rafa gets, depending on the amount of wood (logical) which will rise to 70 ° Ctemperature radiators when maximum performance is fire.

It has interspersed installation with existing gas boiler, can operate both at once, but when you turn the fireplace, avoid connecting the boiler (that activate guess with a thermostat in the living room).

Expansion tank 12 liter safety valve that opens at 3 bar + (connected to drain) and automatic air vent

Details of all the outdoor installation:

Connections of the entire system

Top left is the safety valve 90 , through which the hot water goes down the drain in case of overheating (over 90), which is mandatory in all closed heating system that depends on the proper functioning of an electric pump to be safe.

By having the sensor in the pan, this system prevents you from having to install a UPS to keep it running in case the power goes out, but security has installed one connected to a car battery 12V 100Ah and since copper It is very fragile , and it is possible that temperature and pressure can break before the safety valve is activated. To the right of all looks, with its black top round, and manometer, automatic key that keeps the circuit the set pressure (which works by the tension of a spring), opening the water inlet if lower, which is set to 1.5 bar, which would be that would put fresh water in case of failing light and activated safety valve.

Below the two circulation pumps one for upstairs and one downstairs of the house, right pump is electronic and has an automatic purge to remove air circuit; this redundancy gives greater security in the event of a pump failure. To the right of the pumps there are two anti-condensation mechanical valves , its function is that no water too cold circuit of the chimney, preventing water from accumulating (and thus smoke and soot) on the coil, reducing maintenance for this reason coil (recirculates the water to the coil until it reaches the setpoint temperature of 55 ° C, which is when they start to divert water to the radiators, and 65 completely open Step radiators. If you can appreciate a lilac keys are your check time not to influence with each other, and that water does not go into the boiler.

The two red keys on the right in the photo above are the drain in an emergency.

In total radiators has 140 members spread over 5 radiators down and 7 above. 

Circuits with different temperature

Rafa told me that the only problem he has now is that, despite having divided each plant in a separate circuit, each with its own pump, do not get enough temperature radiators down , as if the above "stolen" almost all the heat, and until they are hot, do not begin warming the below. I believe that the most likely cause is the different flow of both facilities , the pumps are not exactly the same, and although they are configured to the same RPM, anything that changes a turbine to each other, the more efficient the leading percentage of water and heat. The only thing I can think of to fix it is to put some system to match the flow between the two circuits , because although pumps were equal, each circuit has its various power demands for the same flow rate, matching lead both floors flows the same amount of heat, so that with a single circulation pump might suffice for both floors (provided it does not exceed its capacity ). If any kind reader knows some kind of valve or system easily solve it, please comment, I'm sure Rafa will be happy to hear from you. Thanks Rafa per share, has been a pleasure would contact me, we learned a lot with your installation!

DISCLAIMER

I share this instructions "as is", with the sole intention of sharing the results of my experiments and others to not make the same mistakes; please refrain from implementing them if you do not have adequate means and knowledge, I will not be responsible for any consequence or damage arising. "Science, if not open, is not science."