Gas pressure problems, use of MDPE pipe outside?

[Halesowen1]

What I meant was fitters dont get away with it on any contracts I am on, we have every job inspected by our own company and then by the initial company themselves.
But the difference is our work is surveyed properly in the first place, if you know what problems wil arise then you can rectify before it does, hence 28mm pipe on most of our jobs.
Its that initial survey that counts a lot I reckon, if you have the parts there and the knowledge that your work is gonna be checked twice, then believe me you do a good job and make sure its to ALL reg's.
I used to subby to a company doing all there surveys and inspections, I saw at least a dozen teams sacked in 12 months, I would put down x amount of 28mm gas due to boiler, pipe run and other appliances. Only to find that on the inspection after the work had been completed there was a 3mb drop on working pressure and no 28mm fitted, it had all been scrapped. Fitters reckoned it didnt need it when I asked so they were made to go back buy the 28mm themselves, fit it in there own time and when it was done, sack them. Poor workmanship is only going to lead to loosing contracts.

 

[AWheating]

You wont get away with it at any of my local councils nor on Warmfront scheme, if its got more than 1mb drop then you upgrade the gas.

If you had seen the warmfront install at my mothers house then more than a 1mb drop would be the least of my concerns. The fact i had to repipe 75% of the heating system, the condense, blow off, re make 50% of the rad tails with enough ptfe, alter flue gradient......... infact it would be easier to list the things that was done correctly..... cant think of any thing! LOL

 

[< 0.004 = :-)]

What I meant was fitters dont get away with it on any contracts I am on, we have every job inspected by our own company and then by the initial company themselves.
But the difference is our work is surveyed properly in the first place, if you know what problems wil arise then you can rectify before it does, hence 28mm pipe on most of our jobs.
Its that initial survey that counts a lot I reckon, if you have the parts there and the knowledge that your work is gonna be checked twice, then believe me you do a good job and make sure its to ALL reg's.
I used to subby to a company doing all there surveys and inspections, I saw at least a dozen teams sacked in 12 months, I would put down x amount of 28mm gas due to boiler, pipe run and other appliances. Only to find that on the inspection after the work had been completed there was a 3mb drop on working pressure and no 28mm fitted, it had all been scrapped. Fitters reckoned it didnt need it when I asked so they were made to go back buy the 28mm themselves, fit it in there own time and when it was done, sack them. Poor workmanship is only going to lead to loosing contracts.

done much installing yourself? your talking about sacking decent men here, who ve went back to put things right and then you sacked them? you could end up with a sore face treating men like that. you would if you tried that up here anyway.
Any idea how much the fitters are getting per system ?
just had an agency send me the prices they re offering for contract work with a national utility co. (not BG)
additional pipe - £7/3m copper LOL , thats alright if you ve got miles of straight runs , but when your working in occupied houses, moving furniture,lifting carpets, floorboards, checking joists, forming crossovers cutting in tees, tieing in existing branches, you can see where i m going here, £7 a length is taking the hit or a miss
pay fitters decent money, instead of peanuts, and the quality of the work will rise.

there s 4 man squads doing full systems in a day up here,up to 10 rads all copper, 15mm to rads, combi, gas upgrade. 2 fitters , a joiner , and a labourer . they re getting £450 a system , £150 ea fitter, £100 joiner and £50 labourer . sounds allright but its head down , backside up from 7.30 in morn till 7,8 or 9 at night, with up to an hour and half travelling each way. fitters are knocking their pans in for a £10 an hour , can see whythe gas upgrade gets swerved and the buckshee copper yadded , the squads don t get the scrap cylinders , fat cats even want that now.

 

[fuzzy]

im waiting to hear from the op

 

[Chris H]

It would appear you are suggesting I shouldn't have had a 37kW boiler fitted? The gas pressure problem was always a possibility and now its here a solution is sought. I am not Gas Safe Registered and do not intend to touch or alter any gas connections and will employ a gas safe registered person to do this (preferably the plumber who installed the boiler). However, I would like to explore the options with open minded experts before committing to one solution or another and discuss the relative technical constraints. I thought that was the purpose of forums such as this?

By the way, how many copper pipes have you left exposed outside that are connected to internal house bonding on a PME service? I don't want you to worry about it and I'm quite happy to share my concerns without fear of prosecution.

Couldn't agree with you more Brian99, this is a forum and raising questions are what they are all about (to me atleast.) Sadly there are alot of sad insecure people on this forum who wish to instantly jump down your throat.
However I would be concerned by who installed your boiler, If upsizing to a 37kw boiler. As a GSR installer the first thought you would have is pipe sizing! Although PE pipe-work is possible, would it not be easier/quicker to re-route internally and up-size. Any good GSR fitter/installer could do some calcs based on distance, fittings and output. Factory sheathed copper pipe is permitted buried in soil as is steel pipe, PE pipe and trac pipe providing they are buried atleast 375mm deep. Whatever happens there will be disruption.
Good Luck.

 

[< 0.004 = :-)]

talking to a worcester engineer a while back, they re happy with min 14.5 WP on a Greenstar CDi (gas valve test point) as long as GR is within tolerances, any lower and they ll shut if off. something about the effect off the fan pulling the gas through. WP aint as important as a conventional boiler that need positive pressure to push the gas through.

worked on council sites where they ve pulled up fitters for flue terminals that are 295 from an opening, made firms take out 3/4" tracpipe and replace with 1" even though there was only 2-2.5 drop and GR was spot on. no other gas appliances in the properties. school boy errors by the fitter but a bit over the top imo even for new builds.

refurbs and grant aided jobs in occupied house are a bit different. knowing the theory and having a gas safe card and clipboard is cool but you can t buy practical experience.

 

[Halesowen1]

done much installing yourself? your talking about sacking decent men here, who ve went back to put things right and then you sacked them? you could end up with a sore face treating men like that. you would if you tried that up here anyway.
Any idea how much the fitters are getting per system ?
just had an agency send me the prices they re offering for contract work with a national utility co. (not BG)
additional pipe - £7/3m copper LOL , thats alright if you ve got miles of straight runs , but when your working in occupied houses, moving furniture,lifting carpets, floorboards, checking joists, forming crossovers cutting in tees, tieing in existing branches, you can see where i m going here, £7 a length is taking the hit or a miss
pay fitters decent money, instead of peanuts, and the quality of the work will rise.

there s 4 man squads doing full systems in a day up here,up to 10 rads all copper, 15mm to rads, combi, gas upgrade. 2 fitters , a joiner , and a labourer . they re getting £450 a system , £150 ea fitter, £100 joiner and £50 labourer . sounds allright but its head down , backside up from 7.30 in morn till 7,8 or 9 at night, with up to an hour and half travelling each way. fitters are knocking their pans in for a £10 an hour , can see whythe gas upgrade gets swerved and the buckshee copper yadded , the squads don t get the scrap cylinders , fat cats even want that now.

I dont sack them, I was only inspecting there work. But the problem is, if they are leaving these problems and blatantly taking the mickey out of the company by tatting the copper in they have been given to upgrade the gas. I dont think the company are doing any wrong, and they aint good fitters if they are not doing there jobs right are they??
Not working to Gas Regs etc, this means companies lose contarcts, multi million contracts for some too.
If it takes 4 men do a 10 rad system in a day then no wonder they are struggling to make it pay. Most on our contarct are 2 men teams and all do 4 installs a week at least.
But not being nasty here, if a company knows they have good fitters then they pay a bit more, anybody can pay peanuts and get monkeys working for them can't they??
Oh and to answer your first question, I have over 15 years Gas exp mainly Heating installs and 20 years plumbing exp. I have done inspecting and surveying jobs in between and bits of auditing too.

 

[Halesowen1]

talking to a worcester engineer a while back, they re happy with min 14.5 WP on a Greenstar CDi (gas valve test point) as long as GR is within tolerances, any lower and they ll shut if off. something about the effect off the fan pulling the gas through. WP aint as important as a conventional boiler that need positive pressure to push the gas through.

worked on council sites where they ve pulled up fitters for flue terminals that are 295 from an opening, made firms take out 3/4" tracpipe and replace with 1" even though there was only 2-2.5 drop and GR was spot on. no other gas appliances in the properties. school boy errors by the fitter but a bit over the top imo even for new builds.

refurbs and grant aided jobs in occupied house are a bit different. knowing the theory and having a gas safe card and clipboard is cool but you can t buy practical experience.

But why do a job thats not to reg's?
295mm is not to reg's and yes its only 5mm but its not right.
2.5mb drop is not allowed, it says 1mb for a reason and Worcester and other companies are handing out leaflets to companies about working pressure drops, they are allowing a bit more now due to gas valves. Think Worcester allow 1mb extra so you are allowed 2mb on them.
But you try telling that to an inspector who only knows the 1mb drop rule.
If you are gonna bend the rules a bit, do it where it aint gonna matter or be seen. Cause the first thing you check is the flue.

 

[< 0.004 = :-)]

not sure 5mm is going to make a difference wether pocs from a fan flue enter a building or not, obviously the further away the better. if they re going to enter at 295mm, why wont they enter at 300mm or 305mm. i thought gas regs were there for safety and guidance for engineers, not to give mini hitler jobsworth inspectors a cushy job and power trip.
i know and work to the regs . 2.5mb drop is allowed, and classed as ncs if not affecting safe operation of an appliance.
you must be installing a lot of 35mm copper if your sizing correctly to houses with multi gas appliances and high output combis then.
i explain this to customers who dont want their expensive flooring ripped up to upgrade a gas supply when the new boiler will operate perfectly well and safely with correct GR , on the existing 22mm supply.

 

[< 0.004 = :-)]

few weeks since last fitted 1 but sure worcester CDi combi MIs state a WP of 16.5 is ok allowing for drop accross the gas valve, their engineers were informed anything less than 14.5 they have to ar.
BG 330 MIs state 15 minimum , if i mind right. i go with MIs .

 

[tamz]

B
But you try telling that to an inspector who only knows the 1mb drop rule.

That rule will change in the not too distant future :wink:

 

[AWheating]

few weeks since last fitted 1 but sure worcester CDi combi MIs state a WP of 16.5 is ok allowing for drop accross the gas valve, their engineers were informed anything less than 14.5 they have to ar.
BG 330 MIs state 15 minimum , if i mind right. i go with MIs .

WB cdi min 18mb in instructions which includes any drop across the gas valve. any install that has more than a 1mb drop is incorrect as per gas regulations, it dont matter what the min value the boiler needs to run correctly. If you have more than a 1mb drop then its wrong, simple.

MI state the min requirements of the applaince, this does not alter the need to correctly size the gas pipework to avoid a drop of more than 1mb.

 

[AWheating]

not sure 5mm is going to make a difference wether pocs from a fan flue enter a building or not, obviously the further away the better. if they re going to enter at 295mm, why wont they enter at 300mm or 305mm. i thought gas regs were there for safety and guidance for engineers, not to give mini hitler jobsworth inspectors a cushy job and power trip.
i know and work to the regs . 2.5mb drop is allowed, and classed as ncs if not affecting safe operation of an appliance.
you must be installing a lot of 35mm copper if your sizing correctly to houses with multi gas appliances and high output combis then.
i explain this to customers who dont want their expensive flooring ripped up to upgrade a gas supply when the new boiler will operate perfectly well and safely with correct GR , on the existing 22mm supply.

2.5mb drop on a new install is not NCS.

cost of materials or flooring is not a vaild excuse to break the regs.

 

[AWheating]

As for 1 day installs, i have yet to see one installed correctly and to the book. if you consider you need atleast 4 hours to commission correctly (cold flush, hot flush after min 2hours, balance etc...) thats why so many engineers have loads of bottles of cleaner on the back of the van. lol

 

[< 0.004 = :-)]

we all know the regs state 1mbar drop between meter and appliance. it's outdated though.
if i can prove a premix burner is working to full performance with correct GR/HI , temp rise on DHW, CA values, no affect on safety of any other appliances, as a gas engineer i m happy as larry. if it s not performing to full performance and is undergassed , then it gets upgraded . thats engineering judgement , and no reg is going to tell me a boiler operating perfectly on a 22mm supply is going to work better on a 28mm

suppose yous all always calculate the IV of the pipework for purging as well lol

tamz knows the script , watch out for a TB on coming soon

 

[AWheating]

incorrect sized pipework on a new install spells cowboy plain and simple, if that how you work then giddy up!

 

[Halesowen1]

we all know the regs state 1mbar drop between meter and appliance. it's outdated though.
if i can prove a premix burner is working to full performance with correct GR/HI , temp rise on DHW, CA values, no affect on safety of any other appliances, as a gas engineer i m happy as larry. if it s not performing to full performance and is undergassed , then it gets upgraded . thats engineering judgement , and no reg is going to tell me a boiler operating perfectly on a 22mm supply is going to work better on a 28mm

suppose yous all always calculate the IV of the pipework for purging as well lol

tamz knows the script , watch out for a TB on coming soon

When the reg is outdated I am sure it will be changed, untill then its best to stick to them. Do you note on your gas cert for the boiler that the Brand New Boiler you have just fitted for the customer is Not to Current Standards?? (You cannot fit a new appliance not to current standrads, that rule is for existing)
No you dont.............. So then you are getting deeper in it.

 

[< 0.004 = :-)]

last cdi i fitted was a 37cdi badged as a BG537i , it has a bit in MIs about the pressure drop through the gas valve =1.5 , so 18 - 1.5 = 16.5 is acceptable. they haven t updated the MI that you download from their site yet

Worcester TB 40 and gsr TB 129 , think i v got the installer mag with the article TB 40 refers too, corgi still send it out for free to ex members. if i can dig it out i ll scan it and post it.

 

[< 0.004 = :-)]

incorrect sized pipework on a new install spells cowboy plain and simple, if that how you work then giddy up!

lol , yeeeeehaaaaa
cowboy s needlessly cost the customer money because they have no clue about gas engineering , and simply follow what the book tells them rather than apply basic engineering.

 

[Halesowen1]

last cdi i fitted was a 37cdi badged as a BG537i , it has a bit in MIs about the pressure drop through the gas valve =1.5 , so 18 - 1.5 = 16.5 is acceptable. they haven t updated the MI that you download from their site yet

Worcester TB 40 and gsr TB 129 , think i v got the installer mag with the article TB 40 refers too, corgi still send it out for free to ex members. if i can dig it out i ll scan it and post it.

I dont get what you are trying to say here, that 16.5MB is OK?? Not if its 22MB at meter mate, then you would be getting 5.5MB drop when you are allowed 1mb plus what Worcester allow now for valve. But max up to 2.5mb deffo not 5.5mb

 

[Halesowen1]

What you are quoting is minimum working pressure, and yes we know that. We are talking about pressure drop from meter to boiler, 1mb max allowed. So yes your boiler can be Ok working at 16.5mb plus the 2,5mb allowed for drop and valve, but then the meter must be only giving 19mb. But what if its 20,21,22,23mb??

 

[AWheating]

not that it matters as whatever the MI say more than 1mb drop in wrong but the WB manual states 18mb (fitted a 30cdi last weekend) at the test point on the gas valve. If you allow 1.5mb drop from appliance gas iso cock to this point then the min required pressure is 19.5mb on entry into the gas iso valve at the bottom of the boiler. with 1mb drop across pipework and you need 20.5mb working pressure at the meter.

as for the worcester tb40 if i remember it discusses issues with high peak times and operation of its boilers within these low pressure periods.

no need to post me anything, i get the corgi mag, the gas safe mag, the worcester mag.... as you are a cowboy you can send me a copy of horse and hound lol.

 

[tamz]

TB40
http://www.worcester-bosch.co.uk/cache/file/20/minimum-gas-operating-pressure.pdf

The boiler manu's know fine well what their boilers will work on. The 1.5mb permissible drop through the boiler is a bit of a smokescreen imo.
I've fitted many where the difference between the wp at the meter and at the test point on the gas valve is less than 1mb. If it can get through some with very little drop then why not others?
The only way to confirm the drop on the pipework is to cut a test point in as it connects to the boiler. Very few do that, for obvious reasons.

 

[AWheating]

lol , yeeeeehaaaaa
cowboy s needlessly cost the customer money because they have no clue about gas engineering , and simply follow what the book tells them rather than apply basic engineering.

please explain these things to you Gas Safe inspector and maybe he will redraft the regs to suit your needs.

 

[AWheating]

TB40
http://www.worcester-bosch.co.uk/cache/file/20/minimum-gas-operating-pressure.pdf

The boiler manu's know fine well what their boilers will work on. The 1.5mb permissible drop through the boiler is a bit of a smokescreen imo.
I've fitted many where the difference between the wp at the meter and at the test point on the gas valve is less than 1mb. If it can get through some with very little drop then why not others?
The only way to confirm the drop on the pipework is to cut a test point in as it connects to the boiler. Very few do that, for obvious reasons.

i agree def smokescreen and anybody relying on the 1.5mb get out of jail free card to cover there undersized pipe needs to rethink what they are doing.
Tested a 30si friday and i got 20.2 at the boiler and 21 at the meter, no 1.5mb drop in sight.

 

[Halesowen1]

Worcester boilers are probably the best for this, you dont get many Worcester boilers with more than 1mb drop anyway. Ideal are horrendous, I fitted one of these within 2m off meter, 22mm x2m and it dropped 2mb. Rang Ideal and they told about new allowed drops through valve.

 

[Halesowen1]

I dont think it is a smokescreen, some boilers like Worcester dont lose any through the valve, but others do and lose 2mb.

 

[AWheating]

well its a smokescreen because some engineers use the figure to justify poor work and having 16.5mb WP. If i was a customer who's 1 year old boiler had a NCS/warning notice on its anual service i would not be to impressed.

 

[< 0.004 = :-)]

When the reg is outdated I am sure it will be changed, untill then its best to stick to them. Do you note on your gas cert for the boiler that the Brand New Boiler you have just fitted for the customer is Not to Current Standards?? (You cannot fit a new appliance not to current standrads, that rule is for existing)
No you dont.............. So then you are getting deeper in it.

you can install a new appliance ID, never mind ncs if you don t know what your doing. had an LLSC y-day on a property with a new boiler fitted in june. 2mbar drop on an e6. asked tenant if any whiffs of gas, yeh sometimes in the kitchen where new boiler fitted. traced it to leak at the isovalve,. olive squashed into fitting. repaired it and completed the cp12. riddoring aint for me though, leave that to the gas polis.

gas cert for the boiler ? we don t need to notify in Scotland.
fill out the commisioning sheet , with GR/HI, IP/WP and CA results blah blah .
not a chance WB,BG,Vaillant or any large co., who can afford to employ expensive lawyers would leave theirselves exposed by not condemning appliances operating perfectly with lower than stated WP. if there was the slightest safety issue , they be AR-ed to CTA.

do you think gsr are going to come after you if you can prove a boiler is operating safely and to full performance , with more than a 1mbar drop ? they would laughed out of any court.

 

[< 0.004 = :-)]

say this one more time , but i doubt the penny is going to drop here .
the 1mbar drop is an outdated reg , from the days of se pre aerated burners.

i m mainly talking about replacing existing se combis with condensers. when going by the book , the gas should be at least kicked off in 28mm. houses that have finished hardwood floors throughout. a total nightmare to upgrade to acheive max 1 drop. and with 4 appliances , meaning a 20m run from meter now becomes an 80m for your calcs to acheive max 1 accross whole installation with everything running at max if we re doing it right (that bit confuses a lot of fitters) and not being cowboys remember, the costs become frightening.

if a boiler with a pre-mix burner works to Manufacturers spec ie , Gas Rate is Spot on , CO2/Co ratio, DHW temp rise etc on an existing supply (swapping standard for condenser, combi-combi) why would you insist on upgrading the gas first ?
would you not say to customer , going by the calculations , i may have to upgrade the gas to acheive a 1mbar max drop to fully comply with current regs blah blah, but this will involve upheaval and expense. the alternative is to install the boiler first , carry out checks, if not acheiving full permormance and it s undergassed i will need to upgrade it. if however it does not require upgraded to achieve full performance, even though your calculations tell you different , then obviously the calculations are costing your customers money they do not need to spend and you are the cowboy Matt Albright is more likely to take an interest in , than the sensible engineers taking he logical approach.

 

[< 0.004 = :-)]

Worcester boilers are probably the best for this, you dont get many Worcester boilers with more than 1mb drop anyway. Ideal are horrendous, I fitted one of these within 2m off meter, 22mm x2m and it dropped 2mb. Rang Ideal and they told about new allowed drops through valve.

new ideals and glow worms have a test nipple on the isovalve , takes away any doubt. bit nippy if boilers been boxed in underneath though, joiners , aaarrrrgggg lol

 

[Halesowen1]

So basically you are saying that you are not going to abide to Gas Reg's??
Well you go ahead.
P.S Looks like your horse needs some water...................

 

[Halesowen1]

If its an outdated regulation I am sure it would have been amended or removed. As all us fitters know the reg's can change from day to day.
But again i will say it, if you want to carry on breaking reg's then do so.

 

[fuzzy]

op says we cannot run bonded pipe outside, so its all academic.........mmmmmmmmmmm

 

[mikimac]

op says we cannot run bonded pipe outside, so its all academic.........mmmmmmmmmmm

If that's the case we should all be rushed off our feet 'cos there's plenty of it around...prepare for a payday guys n gals :rolleyes4: