Hi to all,

My orligno 40kw log boiler has the above mentioned function and i don't know what it's for. Nor does the manual explain.
I am not sure if it's related but when i want to stop the boiler (rather than let it force-burn the last few lumps of charcoal for no good reason that i can think of), i am unable to. If i stop it by pressing the off button it soon takes it upon itself to restart. Only the main switch can stop it but this also stops the laddomat pump which means the boiler doesn't transfer the last of the heat to the store.

maybe this is blow-through, i m not sure. Either way, what is the purpose of this?

Thanks,

john.

Thanks Triassic but I must admit, i still don't get it or understand the reason for it.

I think we have the answer in the following video published by Angus https://www.youtube.com/watch?v=6R01ShNNDAs

I have experienced the 'woompf' one or twice when opening the door. This has happened whilst still getting up to initial heat, before i've started the fan but i understand the reason for blow through now.

What i don't yet understand is why the fan insists on burning up the last of the embers (this is not what blow through is about, i assume). I mean why not leave what's left once the pump is stopped for good and the temp is still falling.

Posted By: johnnyhWhat i don't yet understand is why the fan insists on burning up the last of the embers

From what I've read, its to stop the latent heat over heating the boiler section and warping the steel plates of the boiler.

As Owlman says, the blow through is part of the design, optimise the function by all means, but don't do away with it, until you are sure you understand the potential consequences.

Posted By: johnnyhit's the pointless burning of the last fuel when the boiler can no longer reach a temp that will be passed to the store.

No doubt every gasification WB is different but for me this is not pointless.

Less ash and debris means lees frequent ash box emptying and easier emptying.

'Slumbering' burning is a terrible thing for my WB - I can get some nasty (and dangerous) clogging up with foam-like carbon deposits and of course for sure the flue will become dirtier quicker.

My WB is inside my house and hence the heat is not lost.

My WB has a lot of DIY insulation and, so, is generally 40-45 deg when I begin my burn the following day - this means a super, super fast time up to the gasification mode, and then to 65 deg (when it starts to heat the TS). It also reduces to zero the 'didn't get hot so fire must be out so turn off' I have (set to 45 mins); this setting (ie how long the WB fan is on without having activated the pump to heat the TS) is user definable.

There could be excess heat in the firebox but this could only be reduced by pumping but not by fanning.
I think it is important that wood is not force burned for nothing. so when the 'pump on' setting is 75 then at 74 the fan should stop or at least after 15 minutes at 74 the fan stops. That would leave a few charred remains in the box for tomorrow. Otherwise i'm heating only the flue for the last hour. It's amazing how long it can continue blowing after the pump has stopped. I suppose a well insulated boiler with no heat being removed i.e. pump off, can continue to hold it's temperature and therefore keep on blowing for a long time.

To clarify my problem: my boiler is outside the envelope of the house so all heat generated but not transfered is wasted.

Will do.

Yes the boiler and TS are pretty close and pipework is slightly sloping to encourage thermosyphon so i should be ok in the event of a power cut whilst the boiler is very hot.
Come to think of it though, at the lower end of the temp scale, when we've nearly run out of fuel, even with pump running, once the laddo cartridge is closed then we're pumping and blowing for nothing as no more energy could get to the store anyway.

By the way at this time of year with it now being colder I slumber burn or as Eco Angus call it burn continuous 24/7. This was the advice from Eco Angus themselves. This makes living with Orligno a bit easier so I do not need to worry about those last few embers or the store depleting nor do any of the faffing about with the PO setting. Though I'm about all day to top it up three of for times a day.

The explanation that blow through is to avoid the build up of gasses makes sense to me and whilst in continous/slumber mode i can see the need so as to avoid a 'whoompf' episode when opening the door but when batch burning it shouldn't be necessary as the fan is always on anyway.
My, albeit limited to two months, experience is that once the temp has stopped cycling up and down in between pump on/pump off cylces, then the temp continues to drop till eventually it hits 67 degrees and the boiler turns off. The only thing is that once the boiler has dropped to 71 and the laddo is closed it cannot transfer heat to the store so the fan might as well stop. If the embers did manage to reheat the boiler to a high temp without the fan then the pump would switch on and the laddo would open up again i suppose.

Peter_in_Hungary
It is my understanding that the Laddomat pump should run from start to finish and not cycle on and off. So you light the boiler and the pump and fan run.

Mine too Peter, my Acaso loading valve does.

The laddomat is supposed to keep the minimum temp. of the boiler without external controls switching off the pump. (As I said with the pump off gravity circulation can take place and this is uncontrolled with no mixing of the flow and return to maintain the temp). If the Laddomat is setting the return temp. too low then the solution is not to switch off the pump but to change the thermostat cartridge within the Laddomat for one with a higher temp. setting. (up to 83deg is available)

Turning the pump off could be very counter productive as, if for instance, the bottom of your TS was 40deg. then with the pump off this water temp. would go straight into your boiler under gravity circulation which would significantly cool the boiler. With the pump running if the boiler temp. was low then no circulation to the TS would take place and the Laddomat will provide a closed loop until the boiler temp is up.
With the pump running the return is kept at what ever the cartridge temp. value is, that is the flow mixed with the return to maintain boiler temp.

Why do you think a return temp. of 70 -75 deg will stop gasification. What is the return temp. recommended by the boiler manufacturers?

Posted By: johnnyhI am sure you are right about the problem of water that is too cold entering the boiler but in my manual, for the orligno 200, in one section it says that "optimum boiler's temperature is 85- 90 degrees" and in a separate section of the manual: "proper wood gasification process is assured when boiler's temperature is at least 85 degrees. From what i can gather, most people only see 85 degrees on their boiler at the end of several hours burningall gone.

Maybe something got lost in translation, but I can't see the direct relationship between boiler temperature and the gasification process as the manual is suggesting.
The boiler temp is governed by the loading valve and the gasification process often 1000+ C is governed largely by the fans and their corresponding dampers, which drive the forced air process.
In my boiler the flue temp gauge and the lambda sensor directly controls the latter and both temps ( flue gas and boiler temp are displayed ).
My boiler temp mainly stays within the 70-75 C range when fully firing, as governed by the loading valve. When the accumulator is fully loaded, top to bottom, and the boiler inlet water, via the loading valve, exceeds that range; then and only then, does the boiler temp go up.

Johhnyh, I think you're getting confused as to how the Orligno works generally with the pump, fan and various settings on the Ekoster control panel, unless you have a technical problem somewhere in your installation.

I've been running an identical boiler for over a year now and am still getting to grips with how it all works. If I can PM you my number feel free to arrange a call to me. But in the meantime here's what happens with a batch burn on my setup ...

During a batch burn with the target set at 92c my Orligno 200 will stay in the high 70's for two to three hours. This corresponds to the cool flow (40-50c) from the bottom of the store.

As the hot water slowly descends down the store the return will get warmer. From this point the attained temperature of the boiler will start rising and eventually settle at the target temperature set on the digital control unit (in my case 92c). At this stage the store will, or nearly, be fully charged (depending upon how depleted it was at firing). From now on the fan will stop and the pump continues.

This process takes about 4 to 6 hours depending upon how much the store was depleted at start; how much fuel you load; quality of fuel; and whether the boiler heat exchanger tubes are being kept clean.

The fan will not come back on again until either the Blow Through ocassionally cuts in for 20 secs severy 5 minutes or the boiler temperature drops by a certain amount. In my case when the boiler drops to below 92c-5c (the 5c is the DT setting), i.e. at 86c, the fan will come back on constantly in order to get the boiler back up to target temperature of 92c. If there is enough fuel then it will get to 92c and the process starts over again, otherwise the fan will run continuously until there is no fuel.

During this whole period the pump will keep running continuously until it drops below a certain temperature ... PO - DT (e.g. 65c - 5c = 60c). Unless you change the PO setting near this time you will get heat being transferred from the store back to the boiler as the boiler is cooling to below the temperature in the store.

Eventually when the boiler has dropped by a larger certain amount for a sustained time the boiler will come to the conclusion that there is no fuel left and everything will stop.

Whenever the fan is on and there is fuel sitting on a good ember layer it WILL be gasifying. Open the combustion chamber and see if there is a wacking great big scary flame. If there is no flame when the fan is on with fuel then there is a problem as I had when the heat exchanger tubes clogged up.

Just to confuse things, my store never reaches the temperature set on the boiler despite plenty of fuel. It will rarely get above 86c despite the boiler target being 92c+. The store and Laddomat will show 86c but the boiler will be sitting at 92c. Why ... I have no idea!

Again, I'm happy to chat about the Orligno and its operation.