Blocked heat exchanger - remove boiler to clean?

[mogget]

I do wonder whether the (presumably) cement joints in my clay drains are rotting away with the condensate needed to get that extra 10% efficiency

Unfortunately the ground is clay too so no chance of a soakaway.

 

[Razor900]

If only there was a boiler with a single pipe heat exchanger on the heating side that was 20mm or so in diameter

Oh wait there is

 

[Agile]

You must mean the Intergas!

With fewer moving parts!

And a three year warranty! ( As long as you remember to register it within 30 days )

 

[Bunnyman]

Viessman

 

[Dean744PiN5]

its beyond my comprehension why any boiler manufacturer would produce a heat exchanger that not only blocks relatively easily if the boiler goes onto an existing system but that it cant be flushed out easily either ie separate loops......

edit to say, I presume its because the manufacturers are ever striving to produce the ultimate efficient boiler whereas in reality the average customer would happily pay slightly extra running costs per year to have something more forgiving

It's because in the home land of this boiler, heating systems are treated with the respect they deserve, Including the treatment of the system water, hence sludge is rarely an issue. But over here in blighty heating systems and boilers are generally worked to the bone with little to no thought of any ongoing maintenance or water treatment until it is too late and the system is gunked up.

People only have themselves to blame IMO.

 

[dilalio]

Boiler manufacturers would probably say that if people paid as much attention to the contents of their heating circuit as they did their Mochaccinos then they'd never have any problems with it

Meanwhile... back in the real world

 

[Dean744PiN5]

over in Germany, home owners all over the land are waking up to toasty warm houses......

meanwhile.....in old blighty, everyone is waking up to a noisy boiler and cold house, because they spent all their money on mochaccinos

 

[bernardgreen]

So what about Jerry built houses.........

Not true as "jerry" has nothing to do with the Germans

- The cheap, flimsy constructs of Jerry Brothers - a Liverpool building firm. (Note: I've not been able to confirm the existence of this company).

- The walls of Jericho which, as everyone knows 'came tumbling down'.

- The Romany word for excrement - 'gerry'.

 

[dilalio]

meanwhile.....in old blighty, everyone is waking up to a noisy boiler and cold house, because they spent all their money on mochaccinos

Then they think they'll just call out an engineer who'll fix it with a Phillips in 5 mins for £10

 

[C.J]

You can run it round backwards COLD, but don't let any gas into the boiler.

If it was banging really badly before, the oval tubes of the heat exchanger may be distorted which could lead to ongoing hot spots even if perfectly clean.

Which is louder now, the kettling or the fan/flame? My ultracom 15hxi has 'sung' slightly even at new on a spotlessly clean system, when running at a high flow temperature. (for other forum members, yes the pump is sufficient, dT 17deg)

If you don't need the full 15kw you could turn the max output down to say 12kw.

Might be worth another lot of x800, but I will reiterate that I am not an rgi, just a diyer who owns the cut down glow worm version of your boiler.

The noise is now a fairly quiet thrumming vibrating type sound with just a little ticking in the pipework, I know I could jerry rig some power to the pump but is there a way of just switching the pump on at the boiler without having the boiler heating as well?

 

[mogget]

Thrumming doesn't sound to me like a blocked heat exchanger, you will get some noise from the fan, and quite often a little ticking from the pipes in normal operation. It's hard to quantify without hearing it though.

Is there any way you could post a video of the boiler going through its start up sequence and running?

 

[C.J]

I've heard the fan and it's not that, there is also a little (tiny really) steam train type noise when the flow temp is nearing the 70c I have set it at, when fired from cold it's very quiet, noise only happens at higher temperatures, it was worse when set to 75c.
Before treating and flushing with clean water there was very loud banging in the pipework and the boiler sounded like it was a steam train, the noise now is similar only about 80% quieter.
So is there a easy way to run the pump without heat as I think that is going to be my next move, if it makes no difference I won't worry too much as it's nearly fixed and really I'm just trying to do as complete a cleaning job as I can without calling in "the experts" it works fine really and if previously it was only as noisy as it is now I wouldn't even have thought of touching it

 

[mogget]

I don't think you can turn the pump on continuously on a 415 in the software, but I'm a little hazy on that. Your manual should tell you. Otherwise you could wire the pump to a plug.

As Tony and I said earlier though, you'd be lucky to get absolutely all the muck out.

My personal feeling though is that a forward flush with boiler set to minimum output would be more effective than a reverse flush cold.

 

[C.J]

So if a cold flush is no good why can't I run the heat with the flow in reverse, surely as water is pumped through the heat exchanger it won't matter in which direction it flows

 

[mogget]

It will condense on the wrong part of the heat exchanger, and the boiler software will see the wrong inputs from the thermistors.