Low gas pressure

[wattsie1987]

Where are you testing the pressure at the boiler? If the gas valve Vaillant say upto 3.5 mb can be lost from boiler iso to gas valve test point. I alway fit one right under boiler so I know exactly what my pipe is loosing.

 

[jaydebruyne]

Where are you testing the pressure at the boiler? If the gas valve Vaillant say upto 3.5 mb can be lost from boiler iso to gas valve test point. I alway fit one right under boiler so I know exactly what my pipe is loosing.

Still doesn't account for 1mb drop.. 5.5mbar it dropped in total.. so 1 from meter to boiler, 3.5 from ISO at boiler to inlet on gas valve leaves another 1mbar unaccounted for

 

[Leo21]

Still doesn't account for 1mb drop.. 5.5mbar it dropped in total.. so 1 from meter to boiler, 3.5 from ISO at boiler to inlet on gas valve leaves another 1mbar unaccounted for

Have you checked your pockets?

 

[Leo21]

Still doesn't account for 1mb drop.. 5.5mbar it dropped in total.. so 1 from meter to boiler, 3.5 from ISO at boiler to inlet on gas valve leaves another 1mbar unaccounted for

Have you checked your pockets?

 

[jaydebruyne]

Have you checked your pockets?

Damnit, it's in there too! Lol

 

[wattsie1987]

Still doesn't account for 1mb drop.. 5.5mbar it dropped in total.. so 1 from meter to boiler, 3.5 from ISO at boiler to inlet on gas valve leaves another 1mbar unaccounted for

No but your pipework may not be loosing as much as you initially thought.

 

[wattsie1987]

Still doesn't account for 1mb drop.. 5.5mbar it dropped in total.. so 1 from meter to boiler, 3.5 from ISO at boiler to inlet on gas valve leaves another 1mbar unaccounted for

No but your pipework may not be loosing as much as you initially thought.

 

[jaydebruyne]

No but your pipework may not be loosing as much as you initially thought.

Very true. Dunno wether to blast pipework with a compressor to try clear any blockages or just do a new run. Going round tomorrow to check the gas valve and ISO valve. Will see what they say.

 

[ShaunCorbs]

Where are you testing the pressure at the boiler? If the gas valve Vaillant say upto 3.5 mb can be lost from boiler iso to gas valve test point. I alway fit one right under boiler so I know exactly what my pipe is loosing.

sorry but i disagree the hob wouldnt be going out due to 1 mbar, also ive never found anything near what mis say for gas valve restriction normally around 0.5-1 mbar

 

[Scott_D]

Slow reacting regulator when the boiler fires up?

 

[jaydebruyne]

Slow reacting regulator when the boiler fires up?

Still getting same pressure loss after 10 mins on max rate

 

[jaydebruyne]

sorry but i disagree the hob wouldnt be going out due to 1 mbar, also ive never found anything near what mis say for gas valve restriction normally around 0.5-1 mbar

Worcesters are pretty spot on at 1.5 loss from ISO to valve, plus the 1 from meter to boiler..

 

[wattsie1987]

sorry but i disagree the hob wouldnt be going out due to 1 mbar, also ive never found anything near what mis say for gas valve restriction normally around 0.5-1 mbar

To be honest I've never had 3.5 but have had 2 or so. Your right about cooker too I've had cookers lower than 15 not go out. Sounds like blockage to me and possibly more than 1.

 

[jaydebruyne]

sorry but i disagree the hob wouldnt be going out due to 1 mbar, also ive never found anything near what mis say for gas valve restriction normally around 0.5-1 mbar

Shaun would you reckon blasting it with a compressor is worth doing? I think the guy doesn't want pipework going around his house

 

[Scott_D]

Still getting same pressure loss after 10 mins on max rate

But if it's slow to react, when the boiler fires up the WP at the meter drops for a second and the Hob goes out

 

[ShaunCorbs]

Shaun would you reckon blasting it with a compressor is worth doing? I think the guy doesn't want pipework going around his house

I would install a test nipple below boiler least you know then if it's the boiler or Pipework

 

[ShaunCorbs]

But if it's slow to react, when the boiler fires up the WP at the meter drops for a second and the Hob goes out

Think it's steady and not just on start up

 

[jaydebruyne]

But if it's slow to react, when the boiler fires up the WP at the meter drops for a second and the Hob goes out

The hob only goes out on simmer.

 

[jaydebruyne]

But if it's slow to react, when the boiler fires up the WP at the meter drops for a second and the Hob goes out

The hob only goes out on simmer.

 

[Leo21]

The hob only goes out on simmer.

That special soumds like a dicky hob. Cut a test nipple just underneath the ISO and re test.

 

[Leo21]

The hob only goes out on simmer.

That special soumds like a dicky hob. Cut a test nipple just underneath the ISO and re test.

 

[jaydebruyne]

That special soumds like a dicky hob. Cut a test nipple just underneath the ISO and re test.

I've ID'd the hob. But still getting 5.5mb drop from meter to boiler inlet after disconnecting the hob from the supply. To be honest I'm not really worried about the hob, they can just buy a new one. But I need to sort the pressure issue.

So it's either try and clear the blockage, if there is one, or do a complete new run.

Just toying wether to get a compressor to blow out any blockages :/

 

[jaydebruyne]

Vaillant reckons the boiler needs 28mm from the meter... gonna calculate it properly when I get home as forgotten how to do it :/

 

[ShaunCorbs]

Vaillant reckons the boiler needs 28mm from the meter... gonna calculate it properly when I get home as forgotten how to do it :/

What's your total length and how many elbows ?

 

[jaydebruyne]

Let's say 6m, accessible elbows = 10