Low/ No Gas pressure...please help

[sara275]

hi


i hope someone can help here...


We have built a 2nd storey extension (like a large size loft conversion) and have installed a second boiler to supply about 7 radiators and hot water. We are at the stage where we have connected it all to the gas supply but unfortunately there is not enough/ almost zero pressure being delivered to he second floor and the boiler is simply not starting. The pressure falls all the way down to almost zero when the boiler tries to start. The current supply to which we are connecting is already supplying ground and first floor (about 10 radiators and hot water).


We are stuck and looking at options, do we/ can we:


1. tap into the gas source (before the meter) and (as has been recommended by a private contractor) "T Off" another supply pipe for the second floor? can we get into trouble doing it privately?


2. or do i need to get in ouch with the supplier to get it resolved..?


Would gratefully appreciate your help. i don't have too much faith in the boiler fitter so turning to experts here.


thanks so much


Aaliya

 

[Rickster123]

What size gas pipe work do you have running to the boiler and how far does it run?

 

[JAP&H]

Hi Aaliya

Don't work illegally or employ personnel who are willing to work illegally.

Contact your gas transporter for any work carried out 'up stream' of the meter.

 

[galaxy_plumbing]

do you wanna tap in before primary meter, is that what you mean?

 

[Resolute]

Sounds like you either need to upgrade the size of your pipework, get a bigger meter so it can pass more gas or have a new supply installed for the conversion so you have two meters.

For a larger meter you need to speak to your gas supplier and for a new supply you'll have to contact the gas distributor (if you don't know who it is then just call your supplier).

To t off the pipe before the meter is illegal!

 

[heliotrope]

:joker: This is a wind up isn't it?

 

[sara275]

thanks for the reply guys:

@applumbing - from what i know (approximately) its 28mm going from the meter going up about 4 meter and then across another about 5 meter. It then reduces to 22mm to enter the property to travel into the boiler about 4 meter away.

@galaxy_plumbing - a contractor who works for one of the gas companies (dunno which) has said that he can tap into source (before primary meter) and tee off to get more pressure but i suspect this is not 100% legit?

thanks again

 

[SimonG]

Who installed the boiler?, who installed the gas pipe to the new boiler?

From what you have said in your post it is somebody who shouldn't have.

 

[sara275]

Thanks so much for this reply, it sounds so logical. My only question is if i opt for a bigger meter, will there be any need to mess with pipework/ digging etc? i am dreading the thought of digging pipework to match new bigger meter. i am hoping this option is available without digging.

The other option of new pipes obviously means digging..

thanks

Sounds like you either need to upgrade the size of your pipework, get a bigger meter so it can pass more gas or have a new supply installed for the conversion so you have two meters.

For a larger meter you need to speak to your gas supplier and for a new supply you'll have to contact the gas distributor (if you don't know who it is then just call your supplier).

To t off the pipe before the meter is illegal!

 

[AWheating]

illegal gas/boiler installation???

contact a local Gas Safe registered engineer. We are professionals on this site and wont give you advise on ilegal gas work im afraid.

 

[mountainman]

Sounds like a rejected script from Faulty Towers to me.
Gotta be a wind up. I hope!!!

 

[jtsplumbing]

Did the person who fitted the boiler get it to work ? can-not see how with very little gas, how did they commision the boiler ? has it been registered with Gas Safe ? I think the answer to these questions is NO !!

 

[sara275]

FYI, its a qualified gas safe so called "professional" who has landed me in this mess in the first place!! I am now stumbling on forums for answers.

If you have nothing useful to add, please stay off the thread! That goes for any other frustrated, hater too! Jees!

illegal gas/boiler installation???

contact a local Gas Safe registered engineer. We are professionals on this site and wont give you advise on ilegal gas work im afraid.

 

[sara275]

Hi jtsplumbing

The work is not complete and hence no registration or anything. The boiler didn't work due to the pressure problem. When he tried to turn it on, the pressure dropped to almost zero.

Thanks again for your help, i appreciate it

 

[SimonG]

Did you check his credentials? I know horse and stable door etc. But hopefully you won't have paid him fully.

Can you get a recommendation from friend / neighbour / colleague for a good gsr engineer.

You really need somebody to have a look who knows what they are doing. Good luck

 

[Resolute]

Thanks so much for this reply, it sounds so logical. My only question is if i opt for a bigger meter, will there be any need to mess with pipework/ digging etc? i am dreading the thought of digging pipework to match new bigger meter. i am hoping this option is available without digging.

The other option of new pipes obviously means digging..

thanks

FYI, its a qualified gas safe so called "professional" who has landed me in this mess in the first place!! I am now stumbling on forums for answers.

If you have nothing useful to add, please stay off the thread! That goes for any other frustrated, hater too! Jees!

Firstly, the guys on here give good advice and tend to be very helpful so whilst I appreciate you might be frustrated but don't jump on them or you wont get it!

If you need a bigger meter then it shouldn't need digging providing that the meter can be placed where the current one is situated. Phone your supplier and they will come out and let you know. If the best bet is to install a second meter and T off before the existing meter then depending on where the existing pipework is run will depend on what needs digging up etc. Basically it's very difficult to say without seeing the installation. However if you let us know where you live someone on here might be local and be able to give you better advice/quote for any rectification work that needs doing.

It maybe the case that not only do you need a secondary meter installing but the pipe run to the new boiler might also need upgrading.

Sorry to be the barer of bad news but I hope this advice helps.

I would urge you to check the credentials of the installer though as if they are prepared to act illegally and t off the supply pipe then who knows what else they've done wrong and they may have left you with a potentially dangerous situation.

 

[tweakyboy]

Can you post a picture of the boiler along with the pipework going to it, so we can see what you have going on. When you say the pressure drops to zero what do you mean?

 

[sara275]

hi

and thanks so much again. Sorry to sound cheesed off but tbh the frustration stems from people making it sound as though it is my fault for choosing an idiot. I only went off the fact that he is gas safe. The reason why i am here is because i know there are great people here (the likes of yourself and others helping) and i honestly do appreciate the useful replies as it could potentially help resolve a problem that is proving to be a real pain.

I am located in manchester btw

thanks again

Firstly, the guys on here give good advice and tend to be very helpful so whilst I appreciate you might be frustrated but don't jump on them or you wont get it!

If you need a bigger meter then it shouldn't need digging providing that the meter can be placed where the current one is situated. Phone your supplier and they will come out and let you know. If the best bet is to install a second meter and T off before the existing meter then depending on where the existing pipework is run will depend on what needs digging up etc. Basically it's very difficult to say without seeing the installation. However if you let us know where you live someone on here might be local and be able to give you better advice/quote for any rectification work that needs doing.

It maybe the case that not only do you need a secondary meter installing but the pipe run to the new boiler might also need upgrading.

Sorry to be the barer of bad news but I hope this advice helps.

I would urge you to check the credentials of the installer though as if they are prepared to act illegally and t off the supply pipe then who knows what else they've done wrong and they may have left you with a potentially dangerous situation.

 

[M.Joshi]

As tweakyboy said, are you referring to the pressure gauge on the boiler? That is not related to the gas pressure.

 

[M.Joshi]

hi

and thanks so much again. Sorry to sound cheesed off but tbh the frustration stems from people making it sound as though it is my fault for choosing an idiot. I only went off the fact that he is gas safe. The reason why i am here is because i know there are great people here (the likes of yourself and others helping) and i honestly do appreciate the useful replies as it could potentially help resolve a problem that is proving to be a real pain.

I am located in manchester btw

thanks again

Hi Sara, don't worry i've had the same treatment on this forum after choosing a 'so called' Gas Safe Registered company to do work and things didn't go right. Stick around and you should eventually get some useful advice!

I agree that it can feel a bit intimidating and like a pack of lions ganging up on you when asking basic questions on here! I can (somewhat) understand the frustration from experienced GSR forum members when others carry out sub-standard work.

 

[jtsplumbing]

Hi Sara, sounds like you are splitting the house into 2 seperate flats ! so would be good idea to have own Meters, Did your fitter run a new gas pipe from the Meter ? or has he connected onto excisting pipes in the house ?? maybe he as not had a lot of experience, but please make sure he has is own gas safe number, if he is working for someone else he will not be coverd out side of work, Please be very careful you could invalidate your house insurance.

 

[sara275]

right, i've just had a chat with him and i have more info:

1. the pipe is connected from the meter and the total run to the boiler is about 15metres (5meter up, 5 meter across outside and 5 meter inside property to the boiler)

2. About 10 meters of pipe is 10 meters and then it reduces to 22mm for the last 5meteres to the boiler.

3. The pressure at the boiler is 21mb. The problem arises when the boiler is switched on. When it is on, the gas pressure drops very low.

Is the bigger meter size (i think you said U16) domestic or commercial?

thanks again

Sara

 

[tweakyboy]

So your standing pressure at the boiler is 21mb, what is the working pressure?

2. About 10 meters of pipe is 10 meters and then it reduces to 22mm for the last 5meteres to the boiler.

I hope that is a typo above and the fitter hasn't used 10mm!

Are you able to post a picture of the installation?

Is the bigger meter size (i think you said U16) domestic or commercial?

A U16 meter is a large domestic meter, but your gas supplier will work out what you need.

What gas appliances do you have installed and do you know the outputs of them?

 

[mountainman]

Rather than clutching at straws Sara, if as you say you had a GSR do the installation; why not get a Gas Safe inspector over to look at it and give you a definitive report.
If you didn't get a proper GSR then don't whinge if we think you might have been foolish and say so.

 

[sara275]

sorry, it was a typo

2. About 10 meters of pipe is 28mm and then it reduces to 22mm for the last 5meters to the boiler.

working pressure drops to zero when boiler is switched on. Before boiler switch on, the pressure is 21mb

thanks

So your standing pressure at the boiler is 21mb, what is the working pressure?



I hope that is a typo above and the fitter hasn't used 10mm!

Are you able to post a picture of the installation?

 

[Millsy 82]

What make and model are both boilers? Will it work if the other boiler is not running? I have worked in a block of 4 flats which runs off a domestic meter and has sub meters (additional for each flat) and the boilers would run when all were on so although you may need a bigger meter it probably wont stop it firing up unless other boiler is running.

To me it sounds like pipework is undersized/Blocked/squashed I have seen all 3 when working it only takes a careless plasterer to get a good lump of plaster in a pipe or somebody to drop something on a pipe to kink it stopping the gas from coming through. You might have an inexperianced gas man but it could be something else I would check them out just for peace of mind but if it is 1 of the last 2 it could happen to anybody. (I now always solder cap ends on to stop plasterers filling the pipes)

Do you know where they have taken the gas pipe from if it was me I would run a seperate feed from near the gas meter or put a good sized pipe from meter until they tee off.

 

[M.Joshi]

2. About 10 meters of pipe is 10 meters and then it reduces to 22mm for the last 5meteres to the boiler.

I believe she meant 28mm?

 

[AWheating]

FYI, its a qualified gas safe so called "professional" who has landed me in this mess in the first place!! I am now stumbling on forums for answers.

If you have nothing useful to add, please stay off the thread! That goes for any other frustrated, hater too! Jees!

dont get knarked about a sensible answer. If you re-read your original post you stated we this and we that, so it is easy to take that "we" as you and somebody else (following the common use of the word).

You did not mention that we ment your gas safe registered engineer and yourself. It sounds like the engineer you have is an idiot and does not know what he/she his doing so my original answer still stand in essence get another engineer to sort it out and dont pay the original engineer untill all is sorted out.

 

[AWheating]

btw it sounds like the problem is at the meter or the incomming main, easy to discover this if you are a competent engineer, which yours seem not to be.

 

[diamondgas]

Hi sara :welcome: to the forum

You're guy needs to check the working pressure at the meter with the boiler on! dropping to zero at the boiler I'd say he's got a blockage somewhere!! A U6 meter will supply about 64kW/hr ... Your guy if he's GSR will know all this. If he's running just the one boiler and the inlet is dropping to zero then he's got a restriction somewhere IMHO! Putting a bigger meter in wouldn't make a hapworth of difference if that's the case

 

[sara275]

Thanks Millsy. This could be a possibility as the pipes were exposed during plastering. So just for my reference, when we say blocked pipes, we mean pipes from the first fix?

thanks a bunch

What make and model are both boilers? Will it work if the other boiler is not running? I have worked in a block of 4 flats which runs off a domestic meter and has sub meters (additional for each flat) and the boilers would run when all were on so although you may need a bigger meter it probably wont stop it firing up unless other boiler is running.

To me it sounds like pipework is undersized/Blocked/squashed I have seen all 3 when working it only takes a careless plasterer to get a good lump of plaster in a pipe or somebody to drop something on a pipe to kink it stopping the gas from coming through. You might have an inexperianced gas man but it could be something else I would check them out just for peace of mind but if it is 1 of the last 2 it could happen to anybody. (I now always solder cap ends on to stop plasterers filling the pipes)

Do you know where they have taken the gas pipe from if it was me I would run a seperate feed from near the gas meter or put a good sized pipe from meter until they tee off.

 

[Millsy 82]

Yes it will be pipes put in on the first fix.

I have also put a 22 mm elbow in which had a 15mm cap end in but that blocked completely but would say first fix.

 

[sara275]

hiya

i would prefer a blockage then anything more "complicated". Just for clarification, there is already a boiler in he property. The problem boiler is the second one.

cheers

Hi sara :welcome: to the forum

You're guy needs to check the working pressure at the meter with the boiler on! dropping to zero at the boiler I'd say he's got a blockage somewhere!! A U6 meter will supply about 64kW/hr ... Your guy if he's GSR will know all this. If he's running just the one boiler and the inlet is dropping to zero then he's got a restriction somewhere IMHO! Putting a bigger meter in wouldn't make a hapworth of difference if that's the case IMHO

 

[AWheating]

Hi Sara, don't worry i've had the same treatment on this forum after choosing a 'so called' Gas Safe Registered company to do work and things didn't go right. Stick around and you should eventually get some useful advice!

I agree that it can feel a bit intimidating and like a pack of lions ganging up on you when asking basic questions on here! I can (somewhat) understand the frustration from experienced GSR forum members when others carry out sub-standard work.

the usefull advice is to get a competent engineer, too many so called plumbers give poorly judged answers to questions they dont seem to understand or comprehend the safety issues of. The only correct advise here is to get somebody competent to sort it out.

 

[diamondgas]

hiya

i would prefer a blockage then anything more "complicated". Just for clarification, there is already a boiler in he property. The problem boiler is the second one.

cheers

It maybe that you'll need a larger meter to accommodate the 2 boilers and any other additional appliances, cookers, fires you may have fitted Sara ... However even with them all on that would not account for zero at the boiler though, you'd expect some

Just realised I'm echoing your posts Millsy 82

 

[Resolute]

Having read the further info you've now posted I would suggest taking a working pressure on the original boiler, if this is fine then you can rule out anything wrong with the existing meter and regulator. Then turn off all appliances except the new boiler and see if it fires. If standing pressure is 21mb but drops to zero when it fires it would suggest to me that there is a blockage/restriction in the new pipe run.

 

[Bernie2]

It does seem a bit of an unusual problem. Basically you are looking at two problems I suppose, if you are getting 21mb at the boiler.
If for instance you had a very small pipe going to the boiler, you may still get 21mb, conversely if you had a large pipe you would still get 21mb. The difference being that the large pipe can deliver a lot more gas at 21mb than a small pipe can. So the size of pipe is important. And of course making sure there is nothing blocking the inside of the pipe. I am afraid it is all to common for the likes of plaster to fall down pipes when left open while other trades work in the areas surrounding them. Also solid joints are not uncommon if to much solder has been used.

The usual pressure is 20mb coming out the meter with a permissible 1 mb drop at the appliance. I can't comment on the pipe sizing without a lot more information but just supposing its okay, then why is the boiler not firing?

I assume any air has been released out the gas line? I would have a few bob for every time I had tried to start a boiler on a new install without checking that.

Then of course you have to have a meter that will deliver the required amount of gas for all the flats. The problem is you still need 20mb in the loft with all the other gas appliances turned on. If the pipe is to small or the meter too small you will struggle to get that probably. You can get bigger meters of course but you may come on a different gas price rate if the meter is required to be overly big. It also depends on a few other things as well such as incoming mains sizes and pressures. So its not easy to give you a proper answer. Incidentally I think the meter comes under customs and excise as well as the supplier. I can assure you you do not want customs and excise after you for connecting in the gas main before they have metered it for VAT on the gas.

Try turning all the other gas appliances off in all the flats and then try the boiler. That at least may tell you that the pipe run to the boiler may be okay. What you are actually doing of course is running one boiler off the meter and the meter should be able to cope with that. If the air has not been purged, you can do it yourself by continually firing the boiler until you get a light or if it has a manual gas valve holding the button in flicking the piezo until the pilot light lights. It may take sometime as well, I must admit though the installer should have already done all this for you. Anyway if I can help just post some more and I will try to be a bit more specific.

 

[Millsy 82]

It does seem a bit of an unusual problem. Basically you are looking at two problems I suppose, if you are getting 21mb at the boiler.
If for instance you had a very small pipe going to the boiler, you may still get 21mb, conversely if you had a large pipe you would still get 21mb. The difference being that the large pipe can deliver a lot more gas at 21mb than a small pipe can. So the size of pipe is important. And of course making sure there is nothing blocking the inside of the pipe. I am afraid it is all to common for the likes of plaster to fall down pipes when left open while other trades work in the areas surrounding them. Also solid joints are not uncommon if to much solder has been used.

The usual pressure is 20mb coming out the meter with a permissible 1 mb drop at the appliance. I can't comment on the pipe sizing without a lot more information but just supposing its okay, then why is the boiler not firing?

I assume any air has been released out the gas line? I would have a few bob for every time I had tried to start a boiler on a new install without checking that.

Then of course you have to have a meter that will deliver the required amount of gas for all the flats. The problem is you still need 20mb in the loft with all the other gas appliances turned on. If the pipe is to small or the meter too small you will struggle to get that probably. You can get bigger meters of course but you may come on a different gas price rate if the meter is required to be overly big. It also depends on a few other things as well such as incoming mains sizes and pressures. So its not easy to give you a proper answer. Incidentally I think the meter comes under customs and excise as well as the supplier. I can assure you you do not want customs and excise after you for connecting in the gas main before they have metered it for VAT on the gas.

Try turning all the other gas appliances off in all the flats and then try the boiler. That at least may tell you that the pipe run to the boiler may be okay. What you are actually doing of course is running one boiler off the meter and the meter should be able to cope with that. If the air has not been purged, you can do it yourself by continually firing the boiler until you get a light or if it has a manual gas valve holding the button in flicking the piezo until the pilot light lights. It may take sometime as well, I must admit though the installer should have already done all this for you. Anyway if I can help just post some more and I will try to be a bit more specific.

Or you could test working pressure at meter. If you have 21mbar at meter working and nothing at boiler it will not and can not be air in the pipe as the air will be replaced from gas coming through the meter at between 19-23mbar (21mbar+/- 2) if the other appliances are working it may be that they use alot less gas. An old vaillant vcw gb 242 eh runs at 6.0 mbar high flame so would cope with undersized pipes better than an ecotec plus 831, But if the pressure drops to zero and you have working pressure at meter it will be blocked.

Also if you try to purge a gas pipe through a pilot be prepared to wait a long time. ( there is a proper way to purge but I wont say it here)

 

[AWheating]

Having read the further info you've now posted I would suggest taking a working pressure on the original boiler, if this is fine then you can rule out anything wrong with the existing meter and regulator. Then turn off all appliances except the new boiler and see if it fires. If standing pressure is 21mb but drops to zero when it fires it would suggest to me that there is a blockage/restriction in the new pipe run.

this should be common sense to any gas engineer. This engineer is either an idiot or not a gas engineer??

 

[sara275]

hi all

i can't thank you all enough for the info you have provided so far. Its a lil late now so i cant contact him to get any more info but will hopefully get onto it tomorrow to have him answer/ consider the points mentioned.

i'll sleep a bit better tonight knowing i've had second opinion from some great guys!!!

thanks again

 

[diamondgas]

this should be common sense to any gas engineer. This engineer is either an idiot or not a gas engineer??

:iagree: first school basics you'd hope :iagree:

 

[Resolute]

Good luck and let us know how it goes.

 

[AWheating]

hi all

i can't thank you all enough for the info you have provided so far. Its a lil late now so i cant contact him to get any more info but will hopefully get onto it tomorrow to have him answer/ consider the points mentioned.

i'll sleep a bit better tonight knowing i've had second opinion from some great guys!!!

thanks again

we are here to help

honestly tho, if your engineer needs his customer to ask simple questions on the internet i would be worried about the work thats been done and everything aside consider a second engineer.

 

[diamondgas]

hi all

i can't thank you all enough for the info you have provided so far. Its a lil late now so i cant contact him to get any more info but will hopefully get onto it tomorrow to have him answer/ consider the points mentioned.

i'll sleep a bit better tonight knowing i've had second opinion from some great guys!!!

thanks again

It'd be nice to know the outcome of your issue Sara should you be willing to return to the lions den Were ***** cats really Good night :waving:

 

[stevetheplumber]

cant see why he is getting zero my first thought was he was using the wrong test point on a zero govenor but he wouldnt get 21mb standing on that

 

[Bernie2]

Yes it is a bit peculiar. I am not saying the problem is air although air will compress to give a pressure reading, but it will not ignite. Seemingly the pipe is connected close to the meter and runs directly to the boiler wihtout any branches off. I assume its at least 22mm without to many bends or restricitions so it should work. Unless of course its blocked. I find more information would be needed to give a closer guess. The idea of continually firing the boiler up is about all a none gas person can do without breaking the gas train to check air has been purged. It doesn't however explain why the pressure drops to zero, although a fast acting gas valve can do that. Its hard to find out there are so many ifs and buts.

 

[wheeto]

A U6 meter will supply about 64kW/hr ... Your guy if he's GSR will know all this.

64kW/hr? What sort of unit is that? Are you sure you're GSR?

 

[galaxy_plumbing]

Gas Meters - Information if any doubt Second row.

 

[northstar]

hi all

i can't thank you all enough for the info you have provided so far. Its a lil late now so i cant contact him to get any more info but will hopefully get onto it tomorrow to have him answer/ consider the points mentioned.

i'll sleep a bit better tonight knowing i've had second opinion from some great guys!!!

thanks again

Hi did you get the problem fixed ?

 

[diamondgas]

64kW/hr? What sort of unit is that? Are you sure you're GSR?

Yes is the short answer to your question but here's the long hand answer:

U6 meter - 6m[SUP]3[/SUP]/hr of gas

Here's the maths wheeto:

Heat input = (Gas Rate x Calorific Value of gas)/3.6

or

(6 x 38.6)/3.6 = 64.33 kW/hr

A U6/E6 meter will therefore supply appliances up to the value of 64kW max guaranteed! Any more than that required for the property and you'll require a larger gas meter!