gas boiler rustic setting dedeleco

[manet42]

I have never had to "sleep" with my De Dion-Bouton boiler, its thermostat regulates everything without touching it for 10 years !!

I would like to learn how his "rustic gas" works.
Indeed, I monitor 3 gas boilers:
A Budérus (at my mother-in-law's).
A Saunier Duval (at my daughter's).
From afar, a Chafautaux and Maury with ECS at my son's house.
They are all adjusted with a room thermostat (sensitive to 0,5 °) and a valve on the heating body to modify the T ° of the radiators.
If one does not want a succession of hot-cold in the houses, between cold period (-10 °) and mild (5/10 °), the valve must be modified.
With the Budérus and cast iron radiators, it is less sensitive.
On the other hand, the production of domestic hot water in my son is irregular because it is subject to debit.
So here too, it is not ideal, even if it is simple.

JC

[dedeleco]

I do not understand the question, because never a single fluctuation of T in me more than the hysteresis of the thermostat !!!!

Give the diagram of your gas boiler to find out and explain where the problem comes from.

but everything is in the basic thermal regulation links, which I gave you, if I want I regulate a house to you better than the tenth of a degree, as for a high precision oven, with basic PID; but all or nothing simple works to the nearest degree !!
Valve (at my house a thermostat) is used to adjust the T of the radiators and therefore the efficiency but does not change the T of the house, except when you reach the maximum power of the boiler in very cold weather where increasing the T increases the power and keeps the T!
But in mild weather, with maximum power, my T remains constant (if you have approximately balanced your radiators) without problem, and in houses over 30 years old with large losses, it is advantageous to heat shortly at high power, with very long downtime, boiler and pipes very cold !!

Before, 34 years ago, during, 10 years, I had a real Chafautaux and Maury gas factory, complicated to pleasure, which I sent to walk before it broke down, nevertheless I regulated the T as well with !!

[Alain G]

Ho the Dede!


Don't push it too much!


It is impossible to adjust the T to 1/10 of a degree without having a Thermostat in each room and especially with a hot water boiler!
It is possible with a hot air furnace by circulating a lot of air but not with a boiler!



Unless you correct the valves based on the outside cold, or you live in a place not too cold or you are better insulated than our residences in Quebec but I doubt it!

[dedeleco]

I did not write T uniform throughout the house, impossible without standardization of T by a very large furnace fan to Alain G.
Anyway the walls and windows are always a little colder.

I was talking about T next to the thermostat.

[Alain G]

OK, I take your word for it!

Excuse me, I misunderstood!

With hot air furnace and central thermostat I easily reach half a degree in all the rooms of the house and this can go to 1 degree by an outside temperature below -30C, the fan with squirrel cage (cylindrical turbine of 35cmx35cm) is huge as well as the distribution pipes.

[manet42]

My question was simple:
How to ensure that the radiators are not too hot in mild weather and not too cold in very harsh winter.
In order to avoid very hot radiators, it is 20 ° C, cut-out, inertia it is 20,5 ° C, the atmosphere drops to 19,5 ° C, inertia 19 ° C (feeling cold) etc. Even worse if P.max and long downtimes .....
In full frost, difficulties reaching 19,5 ° if not P max.
Must act on this valve!
The boilers are simple: a valve to adjust the flow temperature, a room thermostat. They are not gas factories.

[dedeleco]

amusing:

The boilers are simple: a valve to adjust the flow temperature, a room thermostat. They are not gas factories.

well if these are often gas factories, with the adage, why make it complicated instead of simple !!
Put the detailed plans so that I look at the level of complexity !!
A simple boiler (even gas) is a rare gem that is difficult to find, because when you buy it, you never show what's inside !!
My old Chaffotaux put in the trash before his death, preventively, had amazed me by its complexity of membranes and other things !!
They are sometimes very studied machines for a maximum of repairs and maintenance !!!
Opinion based on emergency calls on forums !!
The expansion tanks in hot boilers are designed to give work to repairs.
In my case I solved the problem by putting it elsewhere !!
Finished, it has become punctured !!

This is why I look at Okofen to find out !!!!

Me, there is no valve !! who does what useful ???

There is a simple thermostat which fixes the T max of water in the boiler which then stops, which I can leave on T max, even in mild weather !!
I do not need to mount this T of water in the boiler and the radiators at 80 ° C in cold weather, 50 ° C at 60 ° C is enough, if your radiators are not undersized.

And still I know much more recent gas boilers where there is not this adjustment of T of the water leaving the boiler !!
As for my mother-in-law who burns her fingers on the radiators !!
I even added a second thermostat set at 80 ° C never reached to double the security in case of overheating, which in my opinion is too often unverifiable !!
I don't like unverifiable stuff, so double security !!

Finally, what is important is the size of the radiators, the thermal constants of the different parts, house (often complex with several thermal masses coupled with different time constants and at different T's often overlooked!), Radiators, boiler , pipes, drafts, thermostat position, (avoid being too close to a radiator or in front of an air leak from window or door!), etc.
But if your thermostat samples the typical T of your house heated by its radiators with the corresponding time constant, it works !!
The hysteresis of this thermostat must be adjustable (rare, even if electronic) for a valid operating rate.

[manet42]

A simple boiler (even gas) is a rare pearl hard to find,

Finally, I will continue to modify the T ° of the radiators according to the T ° ext from time to time ..... Change 3 boilers! ...

Like what, gases, granules, each has advantages and disadvantages.

Congratulations on having found a rare pearl, which seems to me as you point out, exceptional.

JC

[dedeleco]

Put the detailed plans so that I look at the level of complexity !!

because sometimes almost nothing improves the functioning.

So show the plans and details to know my reactions !!
The 3-way valve seems useless to me !!

In your place I would not have these problems with your boilers.
but you have to see the details.

The rare pearl is above all to avoid the boilers studied to have repeated breakdowns, for installers who would be unemployed if everyone was like me !!

[Alain G]

Hi manet!


From what I see your problem could be corrected by starting the pump at the same time as the burner starts and giving it a delay of 1 to 5 minutes after stopping the burner to avoid overheating of the body, so it doesn’t there is no unnecessary overheating of the water.

I recommend a Honeywell adaptive thermostat that regulates hysteresis by itself according to what it takes as fluctuation.

I use this kind of thermostat and it works wonderfully well!