No Hot Water

[picasso]

If I understand correctly the op has dropped the horizontal pipe runs down 100mm and then back up again so no chance that is going to circulate using thermosyphon.

 

[sajeel]

Tony have you gone quiet or did you choke on some gas

 

[Agile]

I was waiting for you to tell us why the OP put PTFE tape on the compressions nut threads.

 

[Agile]

If I understand correctly the op has dropped the horizontal pipe runs down 100mm and then back up again so no chance that is going to circulate using thermosyphon.

In spite of that I would have expected it to still work to some extent.

I still think is air in the long horizontal section.

OP, was there some slope in the pipes you replaced?

 

[Steelmasons]

100 mm will have only a very small effect on the gravity flow.

Utter nonsense..
Maybe you could educate us on the circulating pressure (mbar) per metre length of circuit height @ a flow temp of 80c and a return temp of 70c?
If the OP would like to post the length of pipework along with the gradients then maybe you could calculate the circulating pressures in order to determine whether or not circulation will take place.

 

[AGAS]

 

[GiveItAGoIain]

Yes, there was, but not a massive amount. Probably only 5cm over 2.8m.

Thanks for your help everyone... Time to go buy a bit more pipe, take out the kitchen units, cooker, fridge freezer... All for a separate shower.

Next time the wife asks for a new bathroom, I might just move house.

Iain

 

[Agile]

The 50 mm may not seem very much to you.

But it will ensure that air is naturally correctly vented.

Tony

 

[Dan Robinson]

I was waiting for you to tell us why the OP put PTFE tape on the compressions nut threads.

We're still waiting for you to explain how you. Got 10:1 on your Turbomax.

 

[Agile]

That needs me to take off case and measure burner pressure and do a gas rate!

They take time out from enjoying life which is my priority.

On this thread the small down will be balanced by its up although it will add an extra flow resistance.

 

[Dan Robinson]

Come on... You don't need to measure it. Just tell us how you did it

 

[picasso]

On this thread the small down will be balanced by its up although it will add an extra flow resistance.

And yet it does not work.

 

[Agile]

I just turned down the min gas setting.

This is because my lodger insists on running the heating with just the one 1200 W rad in his room turned on.

Of course with a fixed speed fan the excess air will be making it pretty inefficient. But the objective was to prevent cycling.

I tell him to leave bathroom rad on but he turns that off.

 

[ianmcd]

I just turned down the min gas setting.

This is because my lodger insists on running the heating with just the one 1200 W rad in his room turned on.

Of course with a fixed speed fan the excess air will be making it pretty inefficient. But the objective was to prevent cycling.

I tell him to leave bathroom rad on but he turns that off.

Absolute Tosh the boiler wouldnt light

 

[Steelmasons]

I just turned down the min gas setting.

Below 2mb??

Of course with a fixed speed fan the excess air will be making it pretty inefficient. But the objective was to prevent cycling.

Burner certainly won't cycle thats for sure...
In order to achieve the 10:1 turndown ratio that you were expecting I would imagine burner pressure setting for ignition rate to be around 0.1 mb???...could you confirm please?
Thanks in advance.