Overflow pipe for condensate drain.

Merch

I am looking for advice on the above.

I am not currently fitting a condensing boiler yet, but I am putting some new kitchen units in, I plan to build up two walls with some insulation backed plasterboard, partly to improve the insulation , but mostly to build up the walls to suit the measurements of the kitchen unit sizes (so Im not left with spaces that are fitted with trim to finish off, may as well have them insulated).

What I want to do is, fit a pipe that is suitable for a condensing boiler condensate drain, do this now, so that at a later date when I upgrade the boiler, the kitchen units don't have to be disturbed or make things difficult to fit a condensate drain.

I've checked to see if qual-pex was suitable due to the pH of the condensate and it isn't.

So, is overflow pipe like Marley drain pipe? ie the type that uses bonded joints? I've read that 22mm is required and I'd plan to wrap it in an armaflex type pipe insulation and have it buried in the wall, then blanked off until its required at a later date.
Is this the correct pipe?

I'd prefer to minimise any joints, so if it can be gotten in a flexible type pipe, that could be run in one length without bonded joints etc. If this is available, what is it called and can it be gotten cut from a roll or in short lengths?
I plan to leave space to connect it (below/behind the sink) to a sink/dishwasher drain. Can the drain be connected into a fitting that contains a nuetralising agent such as calcium carbonate or is this something that comes in modern condensing boilers?

JohnnieK

I dont think you can get overflow pipe as flexible pipe, but it is the right pipe to get. If there are units at ground level you could run it at low level behind the units. Either way there will be joints but they are only glued joints.

Merch

I want to run it down the wall (behind the insulation backed plasterboard) but dont want to run it too low, when it is in use I want to make sure any condensate flows away positively, had hoped there was something I could do it without joints.

JohnnieK

Surly you will have a joint somewhere. Where is it going to connect into the existing waste? There is a flexible waste you can get but the smallest is 32mm.

Merch

I want to minimise the number of joints, ie one at the boiler end and one at the connection to the drain, I'd prefer no other joints in between either fully or partially behind plaster board.

JohnnieK

As I said the smallest is 32mm. A corrugated flexible waste and you buy the fittings for the ends. Never seen anything smaller. I have looked on-line and cant see anything. Depending on the distance you need Excel Industries do an adjustable appliance hose the stretches to 2.5m. www.excel-industries.com

Merch

Is that the same flexible piping that is used to drain washing machines?

JohnnieK

Yes but it will only stretch to 2.5m and you will need a jubily clip either end.

sullzz

Why can't you run it outside , what are you going to with the safety valve pipe

anthonyos

i love diy plumbers they nearly always get it wrong takes them 4 times as long and by the time they realize they messed it up they are paying a professional to rectify their tempt god loves a trier

Merch

sullzz wrote: »

Why can't you run it outside , what are you going to with the safety valve pipe

Why cant i run the condensate drain outside? well to where? I would then have to connect it to a drain somewhere which is going to look a bit crap, most of the information I have found suggests connecting it to an existing drain and this is the tidiest looking. If you want extra sockets in, do you want someone to tack it over the wall/skirting boards or will you prefer they chased it in the wall, beside you must be aware the condensate is corrosive, even if only slightly, so at the least it will stain the patio.
as for a safety valve pipe, what of it? I dont know why you are referring to something else, I'm just looking to put a condensate drain in while I'm doing other work, if you are suggesting I connect into that?? or are you saying its draining outside?? yes, its a stub of pipe sticking out of the wall, buts likely its pH doesnt make it corrosive, i.e. greater or lower than 7.

[QUOTE=anthonyos;78040139]i love diy plumbers they nearly always get it wrong takes them 4 times as long and by the time they realize they messed it up they are paying a professional to rectify their tempt god loves a trier [/QUOTE]

I'm looking for some advice, I dont really appreciate the smart reply, if you read my post, Im doing other work where I want to put a drain in at the same time, do you suggest I get a plumber in to put in one drain pipe?? what, thats about 2 metres long?
If you aren't willing to contribute constructive advice, why bother??

As its the law, when I am getting a new boiler I will require an RGI, but that will be after the fact/my kitchen units are in, so what then, do you suggest I do? get a plumber in specifically to rip it all out when this could be a year down the road??

DIY plumbers ok can you give me a rough estimate on how much it would cost to replace, 4 wash hand basin taps, and a set of bath taps?

Thanks to those that provided constructive advice, much appreciated.

anthonyos

im sorry i didn't mean to upset you ...if you can afford the space run it in 1 1/4 waste pipe use plenty of glue.were are you planning your final connection ie outside drain or under sink

Merch

No worries, I did my trade as an aircraft mech, I feel that I am reasonably qualified (competent) to do a bit of plumbing connections like taps and other minor repairs, I dont have the specific experience all the time, thats why I ask for specific advice, but i have a lot of time under my belt doing up connections and the like.
I accept that RGI's are required by law and that I wont have their experience to assess and fit the correct size boiler,but I did enough hydraulic connections to feel competent of doing a few taps and stick in a bit of piping anyway, i need to save whatever I can at the moment.
I planned to connect under the sink, however I want to instal the pipe and blank both ends until I am changing the boiler, plus from what I have read, the height I (get RGI to connect)connect and whether I get the drain connected upstream or downstream, basically depends on the boiler requirements as far as I can see, but that wont be my concern, that'll be the RGI's.

Merch

Brazil is on Film 4 now, I often think of central services when I open a thread

Joey the lips

I would keep this inside if i could. No worries about frost then. Also marley is used because of the acidic nature of the water. Copper is not used because of this.

sullzz

Merch wrote: »

Why cant i run the condensate drain outside? well to where? I would then have to connect it to a drain somewhere which is going to look a bit crap, most of the information I have found suggests connecting it to an existing drain and this is the tidiest looking. If you want extra sockets in, do you want someone to tack it over the wall/skirting boards or will you prefer they chased it in the wall, beside you must be aware the condensate is corrosive, even if only slightly, so at the least it will stain the patio.
as for a safety valve pipe, what of it? I dont know why you are referring to something else, I'm just looking to put a condensate drain in while I'm doing other work, if you are suggesting I connect into that?? or are you saying its draining outside?? yes, its a stub of pipe sticking out of the wall, buts likely its pH doesnt make it corrosive, i.e. greater or lower than 7.



I'm looking for some advice, I dont really appreciate the smart reply, if you read my post, Im doing other work where I want to put a drain in at the same time, do you suggest I get a plumber in to put in one drain pipe?? what, thats about 2 metres long?
If you aren't willing to contribute constructive advice, why bother??

As its the law, when I am getting a new boiler I will require an RGI, but that will be after the fact/my kitchen units are in, so what then, do you suggest I do? get a plumber in specifically to rip it all out when this could be a year down the road??

DIY plumbers ok can you give me a rough estimate on how much it would cost to replace, 4 wash hand basin taps, and a set of bath taps?

Thanks to those that provided constructive advice, much appreciated.

You say you dont like smart replies , well im not a fan of them either , i only asked a question to offer some help , no need to get all defensive , the safety valve pipe will not be just a stub of copper it would terminate just above ground level , no more advice will be offered from me with an attitude like that .also if your not confident enough to glue a fitting or fit a joint you shouldn't do the job at all , perhaps get someone who knows how to do it and is willing to use the appropriate fitting instead of looking for a flexible pipe to use as a shortcut .i wouldnt want to fit a boiler after the homeowner fitted a pipe hidden within the wall , as you said yourself the condense is acidic.

heinbloed

The flexible pipes Merch is looking for are called " flexible condensate (drain) pipes "

They are connected straight to the condensate trap and fed into a junction wherever it suits.
The connection between flex-pipe and fixed sewer pipe can be a flexible plug, similar to that from the washing machine or dish washer.

All these devices are ready available from the plumbing shop, the 25/20mm flex pipe (used for example for Vokera boilers) costs around €1.-/m, the plug to join the fixed pipe (without glue as well) costs around € 1.- as well.

The flex pipe can be glued spot-wise to the wall using the same mineralic glue as for the wall boards.

Mind that a lack of thermal insulation (the condensate pipe installed within the wall insulation) might cause a cold spot, consequently condensation might appear.

If the boiler is purchased by mail-order most dealers can supply the flex-pipe and plug as well, check their catalogs.





You meet some installers in this forum you wouldn't like to hire....


First links via google:

http://www.mcalpineplumbing.com/traps/condensate-fittings/190-flexible-to-rigid-overflow-pipe-straight-connector.html

http://www.reece.com.au/hvacr/products/9502294

There is a lot more out there.

sullzz

heinbloed wrote: »

You meet some installers in this forum you wouldn't like to hire.....

Yeah very true you should hire a " heating engineer"

heinbloed

A heating engineer would certainly not use clips to fix heating pipes or flexible non-pressurised condensate pipes.
He or she would propably sign an expertise to bring such installers to court when asked for.

Responsible engineers in this country and half of the plumbing industry would meet in the workhouse.

PS

Whilest heating engineers have no problem finding a job abroad on the continent (the midle European countries are looking eagerly for heating engineers due to the boom in the building/heating/water/gas/energy industry) the Irish plumber/installer seems to be stucked with the Anglican countries as a choice to go.
No brain drain worries from this side, see

http://www.irishtimes.com/newspaper/breaking/2012/0410/breaking18.html

Joey the lips

heinbloed wrote: »

You meet some installers in this forum you wouldn't like to hire....


.

If you start off down this road i will just ban you and leave you stewing or too the CMODS. No problem to me.

Try a little tact.

There was new protocol brought in to deal with upsetting the neighbourhood. I have reframed from using this because i am very liberal

But i am sure i speak for nearly everyone when i say you truly can be a right pain in the arse. Please stop. Despite what you think your opinion is valued your attitude is not.

Merch

Quote:
Originally Posted by sullzz
Why can't you run it outside , what are you going to with the safety valve pipe

Why cant i run the condensate drain outside? well to where? I would then have to connect it to a drain somewhere which is going to look a bit crap, most of the information I have found suggests connecting it to an existing drain and this is the tidiest looking. If you want extra sockets in, do you want someone to tack it over the wall/skirting boards or will you prefer they chased it in the wall, beside you must be aware the condensate is corrosive, even if only slightly, so at the least it will stain the patio.
as for a safety valve pipe, what of it? I dont know why you are referring to something else, I'm just looking to put a condensate drain in while I'm doing other work, if you are suggesting I connect into that?? or are you saying its draining outside?? yes, its a stub of pipe sticking out of the wall, buts likely its pH doesnt make it corrosive, i.e. greater or lower than 7.

sullzz wrote: »

You say you dont like smart replies , well im not a fan of them either , i only asked a question to offer some help , no need to get all defensive , the safety valve pipe will not be just a stub of copper it would terminate just above ground level , no more advice will be offered from me with an attitude like that .also if your not confident enough to glue a fitting or fit a joint you shouldn't do the job at all , perhaps get someone who knows how to do it and is willing to use the appropriate fitting instead of looking for a flexible pipe to use as a shortcut .i wouldnt want to fit a boiler after the homeowner fitted a pipe hidden within the wall , as you said yourself the condense is acidic.

Only half that reply was to you, the first half ??
My safety valve pipe terminates just beside the flue, I haven't noticed any being terminated just above the ground, assuming we are talking about the same thing?
I never said i wasn't confident to glue a fitting? I'm not looking for a shortcut, I was looking to use the appropriate piping for the job, someone else (a few people) suggested there is a flexible type that is suitable. It makes common sense to use the minimum of joints possible.
I know its corrosive (I've read acidic or alkaline, but corrosive to say the least) thats why I'm looking for the right item.

So how do you suggest you would approach a job that has either no drain fitted, where would you take it? I am curious as to how you would run the drain if the owner wanted it hidden and not just drilled through the wall and then what tacked along the wall and piped into an external drain? what about freezing conditions?
or
A drain fitted but the home owner did it? lets just say they told you they sourced the correct pipe type/material and you could see they were careful enough to blank both ends, are you saying that this is different to a pipe you may fit? and that you would refuse to use it?

Thanks to the people that have offered helpful and constructive advice, the reality is I cannot justify paying someone to fit a pipe that I intend wont be used until my existing boiler is replaced, it just doesn't make sense, I am equally as qualified and competent enough to do it, I'd be foolish not to.

The RGI is responsible for the condensate pipe work, the boiler manufactures instructions dictate fitting requirements for the boiler you want to fit in the future not you or the RGI, if you could pick the manufacture you may want to use in the future Viessmann, Worcester Bosch etc... and use their current requirements as though your fitting it now and ring them for clarification, if not you may find further info here:http://www.idhee.org.uk/ExceptionsGuide.pdf

What you want to do is a bit different and in my mind wouldn't be a problem unless there was a problem down the road and if it didn't meet manufactures instruction it could cause you problems, Gary.

Merch

I've come across that document in a slightly different format. I really had planned to do intensive research into getting a boiler that suits my requirements and is going to be as cost effective as possible over the longterm, but at a later date.
Which means I do that now or make a space behind the insulation backed plasterboard or make a space and install suitable flexible pipe that may suit but which can be extracted if it doesn't.

shane0007

Merch wrote: »

Why cant i run the condensate drain outside? well to where? I would then have to connect it to a drain somewhere which is going to look a bit crap, most of the information I have found suggests connecting it to an existing drain and this is the tidiest looking

You can install a purpose made soakaway. McAlpine make them. I used them whenever there is not a drain close by. Just core drill a 125mm hole in the ground to a depth of 300mm, insert the soakaway and fill with limestone to neutralise the acidic discahrge from the condensate. Job done. They are designed for that exact purpose.

Heatmerchants stock them (Code U47831 : Price €26.07 plus VAT)

Note that all internal condensate pipework should be minimum of 22mm diameter and all external should be minimum 32mm but kept to a maximum length of 3m externally. Ensure all joints are sealed joints internally, as if there is a failure of the trap or water drying out, POC's can be discharged through it. Piped into an open washing maching or dishwater is not acceptable. It must be a sealed joint.

Merch

shane0007 wrote: »

You can install a purpose made soakaway. McAlpine make them. I used them whenever there is not a drain close by. Just core drill a 125mm hole in the ground to a depth of 300mm, insert the soakaway and fill with limestone to neutralise the acidic discahrge from the condensate. Job done. They are designed for that exact purpose.

Heatmerchants stock them (Code U47831 : Price €26.07 plus VAT)

Note that all internal condensate pipework should be minimum of 22mm diameter and all external should be minimum 32mm but kept to a maximum length of 3m externally. Ensure all joints are sealed joints internally, as if there is a failure of the trap or water drying out, POC's can be discharged through it. Piped into an open washing maching or dishwater is not acceptable. It must be a sealed joint.

Appreciate the advice, I would prefer an internal drain than an external or a soakway, but its an option I suppose and a lot cheaper than i had thought, If using an internal drain it would definitely be a sealed joint, I didnt realise POC's might be discharged through the condensate line, I assumed there was some kind of separation device/chamber/trap in the boiler that prevented this.
edit, I've actually come across recommendations to use 3/4" which is less than 22mm, the length of the line would be no greater than 2 metres anyway.

shane0007

Yes, there is an internal trap within the boiler to stop the POC's from entering the condensate pipe, however, should this dry out or fail it can happen. If dried out, it will quickly refill from condensation production from the boiler itself. If it fails, this is where issues can arise. A rare occurence, but it does happen, usually due to ill fitting and more common with oil boilers where the trap is installed by the installer rather than factory installed.
You could actually use corrugated stainless steel pipe as condensate pipe, expensive but for example, I have lots let over from solar installations, but there will always be a problem with a transitional joint from s/s to plastic. The joint cannot be copper or brass. Stick with plastic. It's cheap and it works. 22mm is only a couple of euros for a 2m length.

You will, as previously commented, require the 3 bar safety valve piped to within 100mm of ground level externally. This can be brought down internally and then exit at low level to eliminate an eye sore pipe running down the wall externally. The reason for why your existing pipe is not acceptable is because if that was to discharge when you were walking past it at the point of it discharging, it will be released at minimum 3 bar pressure and more than likely at scalding temperatures. At the existing location, your face will probably take the worst of it. At 100mm from the ground and pointing at the ground, a likelyhood of no injury will occur.

Merch

shane0007 wrote: »

You will as previously commented, require the 3 bar safety valve piped to within 100mm of ground level externally. This can be brough down internally and then exit at low level to eliminate an eye sore pipe running down the wall. The reason for why your existing pipe is not acceptable is because it that was to discharge when you were walking past it at the point of it discharging, it will be released at minimum 3 bar pressure and more than likely at scalding temperatures. At the existing location, your face will probably take the worst of it. At 100mm from the ground and pointing at the ground, a likelyhood of no injury will occur.

I wasn't sure what the poster was suggesting when they brought up the safety valve, I thought they were trying to suggest that a condensate pipe should be tee'd into it (which to me seemed ridiculous) or merely implying that it drains outside, so why would there be a problem draining a condensate pipe externally.
While it's in a place that isn't convenient to walk past the safety valve discharge pipe, it would be possible to be standing beside it, as this was how the house was constructed as a new build many years ago as part of a large estate and as far as I can see all others are the same (Im not saying that is correct, just that they are that way, not only mine), I've also seen many others that way elsewhere, from that perspective I think I will include a copper pipe down the inside leading to outside but blanked off so nothing crawls in and blocks it and ready to be connected when a new boiler goes in.

These are the reasons i come here for advice as it allows me to plan for what would otherwise be too late/add unnecessary cost to implement easily afterwards.

shane0007

He was just pointing out that regulation and he was perfectly correct. Nearly all previous installations carried out in Ireland ignored regulations. With gas, there are a few little ticks introduced to the certification process that now has a little more comeback to the installer should problems or challenges arise. If he ticks the box to state that it is installed as per regulation, then he must install as per regs. Regs normally make sense and they are there for the safe operation of the appliance, in that it is safe for the user and surrounding persons that it may affect and that the appliance can operate as the manufacturer intended it to.

Running a 22mm condensate pipe and a 1/2" copper pipe down at this stage makes good sense. I wish all my clients done this before I arrive to install their boiler! I usually get "uhhh, does those pipes have to go there?"

Also ensure that you have 4 core cable going to the boiler location. You should already have, but no harm in checking while the fire is hot.

shane0007

shane0007 wrote: »

You can install a purpose made soakaway. McAlpine make them. I used them whenever there is not a drain close by. Just core drill a 125mm hole in the ground to a depth of 300mm, insert the soakaway and fill with limestone to neutralise the acidic discahrge from the condensate. Job done. They are designed for that exact purpose.

Heatmerchants stock them (Code U47831 : Price €26.07 plus VAT)

Note that all internal condensate pipework should be minimum of 22mm diameter and all external should be minimum 32mm but kept to a maximum length of 3m externally. Ensure all joints are sealed joints internally, as if there is a failure of the trap or water drying out, POC's can be discharged through it. Piped into an open washing maching or dishwater is not acceptable. It must be a sealed joint.

Without sounding like a miserable basturd:eek: but some manufactures require a larger diameter pipe to feed the condensate pipe from the boiler in to, creating a air gap to prevent condensate backing up and filling the combustion chamber, only a problem if it happens and there would be no warranty cover as the damage is quite bad, PCB, gas valve, fan, insulation commonly would require replacing.

shane0007

shane0007 wrote: »

He was just pointing out that regulation and he was perfectly correct. Nearly all previous installations carried out in Ireland ignored regulations. With gas, there are a few little ticks introduced to the certification process that now has a little more comeback to the installer should problems or challenges arise. If he ticks the box to state that it is installed as per regulation, then he must install as per regs. Regs normally make sense and they are there for the safe operation of the appliance, in that it is safe for the user and surrounding persons that it may affect and that the appliance can operate as the manufacturer intended it to.

Running a 22mm condensate pipe and a 1/2" copper pipe down at this stage makes good sense. I wish all my clients done this before I arrive to install their boiler! I usually get "uhhh, does those pipes have to go there?"

Also ensure that you have 4 core cable going to the boiler location. You should already have, but no harm in checking while the fire is hot.

No good to you if you have low voltage/no voltage switching, if you run both together you can get induction firing the boiler intermittently when the programmer is off, it's best to split the wires in to separate cables.

shane0007

gary71 wrote: »

No good to you if you have low voltage/no voltage switching, if you run both together you can get induction firing the boiler intermittently when the programmer is off, it's best to split the wires in to separate cables.

You can with a relay

JohnnieK

shane0007 wrote: »

You can with a relay

Cheaper to run two separate cables.

shane0007

gary71 wrote: »

Without sounding like a miserable basturd:eek: but some manufactures require a larger diameter pipe to feed the condensate pipe from the boiler in to, creating a air gap to prevent condensate backing up and filling the combustion chamber, only a problem if it happens and there would be no warranty cover as the damage is quite bad, PCB, gas valve, fan, insulation commonly would require replacing.

You're not, but how would a boiler keep firing and keep producing condensate when the flame chamber is full of water? Also why is said manufacturer using a 22mm outlet pipe from the trap and to the trap, etc. Surely rectification would be affected.

shane0007

shane0007 wrote: »

You can with a relay

Correct, which is my usuall advice to sparks when the wrong cabling is used, then some moan about the expense of relay and also wire them within the boiler casing, which did have a level of protection from water but has none after the relay is fitted but PCB's are getting cheaper:D

shane0007

I got caught myself with a Vokera 25A. I ran the cable in the same core from the motorized valve. Took me ages to discover what I had done wrong. A relay came to the rescue.

Merch

shane0007 wrote: »

He was just pointing out that regulation and he was perfectly correct. Nearly all previous installations carried out in Ireland ignored regulations. With gas, there are a few little ticks introduced to the certification process that now has a little more comeback to the installer should problems or challenges arise. If he ticks the box to state that it is installed as per regulation, then he must install as per regs. Regs normally make sense and they are there for the safe operation of the appliance, in that it is safe for the user and surrounding persons that it may affect and that the appliance can operate as the manufacturer intended it to.

Running a 22mm condensate pipe and a 1/2" copper pipe down at this stage makes good sense. I wish all my clients done this before I arrive to install their boiler! I usually get "uhhh, does those pipes have to go there?"

Also ensure that you have 4 core cable going to the boiler location. You should already have, but no harm in checking while the fire is hot.

With the additional information you provided, I can see that seems to have been what they were suggesting, although their initial referring to the safety valve pipe didnt make sense to me, as I wasn't sure what they were trying to say (ie thought they were saying if the safety valve drain/outlet is going down the wall, then why not another condensate drain/edit or tee in condensate drain). My installation was prior to 2000, Im uncertain if those regulations were in place at the time, mine isn't even down to the ground, its practically at the level of the boiler. Anyway, I prefer not to have too many external pipes, mostly the look of it, but also to limit the possibility of freezing.
I haven't checked the existing wiring, but its something i will look at to confirm, there are minimal controls so its only the existing wiring from the fused spur and the mechanical timer.

shane0007

shane0007 wrote: »

You're not, but how would a boiler keep firing and keep producing condensate when the flame chamber is full of water? Also why is said manufacturer using a 22mm outlet pipe from the trap and to the trap, etc. Surely rectification would be affected.

The boiler will continue to fire, the combustion chamber will half fill with condensate then flow down the mixing arm filling the fan then the gas valve and spilling out on to the PCB, the mixing arm is lower than the electrodes and the flame will stay stable but the CO levels will be off the charts.
I had it recently when a fruitloop forgot to take the plug out of the condensate pipe, I got there just before it shaged a 3 day old boiler. I suppose it help the working pressure was 8 mb on a 30 kw boiler, that would be the 1/2 supply then:)

shane0007

shane0007 wrote: »

I got caught myself with a Vokera 25A. I ran the cable in the same core from the motorized valve. Took me ages to discover what I had done wrong. A relay came to the rescue.

I don't know many big words but induction is one of them, I work for a company that made one of the first low voltage connections and the pain of finding that fault still reqs a stiff brandy and cuddle:o

shane0007

I never stop learning. The beauty of boilers!

shane0007

gary71 wrote: »

I don't know many big words but induction is one of them

Yeah, I met somebody by induction once, or could that have been by introduction.... No, actually I think it was by induction! I confuse myself sometimes.

shane0007

shane0007 wrote: »

I never stop learning. The beauty of boilers!

The more a learn the more, I relise what I don't know:eek: I wish I could go back a few years, I had all the answers then and getting chicks was well easy:cool:

JohnnieK

A very good man got me into the habit of bringing the gray and orange cables back to the boiler separately. I do it on any boiler I work on now so hopefully I won't have that problem.

I installed 6 of those mynute A boilers on a job last year. All had relays because they were all pumped zones, no zone valves.

Merch

gary71 wrote: »

Without sounding like a miserable basturd:eek: but some manufactures require a larger diameter pipe to feed the condensate pipe from the boiler in to, creating a air gap to prevent condensate backing up and filling the combustion chamber, only a problem if it happens and there would be no warranty cover as the damage is quite bad, PCB, gas valve, fan, insulation commonly would require replacing.

Prmarily, Im trying to make it easier for when someone installs a new boiler, in that the condensate drain is in place, (edit and for me, so nothing needs ripping out or can only be done where it looks unsightly)
From the black bolded
Are you saying that some manufacturers require a larger diameter pipe to feed the 22mm condensate drain which would be connected into say a dishwasher/sink drain
or
are you saying that a larger diameter pipe is needed all the way to the point it is connected to the dishwasher/sink drain.

I'm assuming you are saying the first? in which case I could still fit a 22mm pipe and they could feed into it with whatever diameter is required by the boiler instructions. (there is the issue if the rgi in question at the time would think this is acceptable)

From the red bolded part
At this stage Im more curious than anything,one , sounds like youare saying that adding a larger diameter pipe is like adding an air gap that acts to prevent it siphoning condensate back up to the boiler
and also
how could condensate back up that much even without it ? I've read a lot of condensate can be produced (edit under the correct conditions, ie that allow condensing to occur), but surely the boiler would switch itself off if the condensate didnt drain? but why would it not drain?
trying to think why condensate wouldn't drain, if the drain was clear, if its connected to a washing machine/dishwasher drain it seems less likely that the drain will be blocked, maybe a sink drain could have food waste, but other than that I'm curious as to what could cause condensate to fail to drain? maybe someone jamming a load of potato peels down the sink???
Also the damage you suggest sounds catastrophic
How does that damage the PCB,insulation,gas valve and fan??, sounds like a boiler self destructing/blowing up or being driven over with a bulldozer , while I think nothing is impossible, it sounds a bit unlikely, when I'd have hazarded a guess it would have switched itself off by that stage?

edit I can see you replied about a plug not removed while I was writing this, but that seems like an exceptional event rather than a common, I'd hope to go for a boiler that has the PCB somewhat protected from water draining down over this, I'm suprised that I've heard this before (my Mothers gas boiler leaked over the PCB) and that some kind of PCB protection isnt standard??

Merch

gary71 wrote: »

The boiler will continue to fire, the combustion chamber will half fill with condensate then flow down the mixing arm filling the fan then the gas valve and spilling out on to the PCB, the mixing arm is lower than the electrodes and the flame will stay stable but the CO levels will be off the charts.
I had it recently when a fruitloop forgot to take the plug out of the condensate pipe, I got there just before it shaged a 3 day old boiler. I suppose it help the working pressure was 8 mb on a 30 kw boiler, that would be the 1/2 supply then:)

Im suprised there aren't features to prevent some of this? or not continue when one stage of the combustion process or certain other steps aren't met? surely if the condensate isn't draining then there is some kind of internal switch to stop the process?? I thought boilers had become more advanced? I'm also wondering which fault occured first? how can edit further condensate be produced if the boiler isnt burning gas/if even the conditons for condensate to be produced are met?

Let's not over cook this, the condensate pipe will follow certain guidelines, but not all guidelines suit all boilers, manufactures dictate the installation.

Without boring you the manufactures who fit condensate sensors in their boilers are less likly to look for a air gap as the boilers will shut down if the condensate backs up, if they don't have a sensor then they will need a air gap to prevent a back up.

This is no concern if you follow their instructions, a few installers didn't read the boiler manual, fitted incorrect condensate line and in the crazy winter we had they ended up with heavily damaged boilers, I fixed a few under warranty because I'm a lovely fella, but it was so costly I then gave parts and let them fix it themselfs, I don't know if I'll do it again as its not a warranty issue.

The larger diameter is only required where the boiler pipe is pushed in to it, like a funnel, the issues of a blocked condensate pipe are more to do with freezing external pipes, but the warranty issues would still be there if you had a freak incident, rare but strange things happen.

Any installation I have done when I'm not being lazy are all asper the manufactures instructions and anytime a installer moves away from that any issues are on him.

Merch

Merch wrote: »

Im suprised there aren't features to prevent some of this?

yes there is, it's called a air gap;)

Merch wrote: »

I thought boilers had become more advanced?

They are, you only have to fit them properly, it's easy.

Merch wrote: »

I'm also wondering which fault occured first?

What occurred was the installer didn't read the book that came with coloured pictures

Merch wrote: »

how can condensate be produced if the boiler isnt burning gas/if even the conditons for condensate to be produced are met?

They will burn gas, if you cover half a burner it will still burn, the flame picture will be brutal but it will stay alight.

Right, I'm off to bed now or I'll be more grumpy than usuall tomorrow

Merch

ok, well it stands to reason that the specific requirements for the condensate drain are going to have to comply with the manufcturers requirements.
Personally I think i would prefer to have a boiler that has a sensor in the condensate drain
Just one last thing, and Im sure this has been thoroughly cooked at this stage!

For boilers that dont have a sensor, are you saying that an actual air gap is used in the condensate drain? as in an anti siphon device is fitted? or as you have suggested the condensate drain from the boiler is put into an enlarged section of the actual drain to the waste.
In either case this just seems to go full circle that fitting a 22mm (internal) pipe using minimum joints and brought to the kitchen waste drain is accpetable for most situations and adaptions of it to suit individual boiler requirements (height differences between drain connection points) should be relatively easy to make.

Merch

gary71 wrote: »

yes there is, it's called a air gap;)



They are, you only have to fit them properly, it's easy.



What occurred was the installer didn't read the book that came with coloured pictures



They will burn gas, if you cover half a burner it will still burn, the flame picture will be brutal but it will stay alight.

Right, I'm off to bed now or I'll be more grumpy than usuall tomorrow

fair enough, hit the hay myself, my knowledge of the subject has increased and i find it interesting enough anyway, as per which fault occured first, i suppose that is common across a lot of situations, RTFM

Sensors arn't all that as they can fail and you are left with the same issues all be it covered under warranty if your lucky.

The larger diameter is only required so that if it backs up it will spill out like a tundish identifying the problem before it becomes a drama.

shane0007

JohnnieK wrote: »

Cheaper to run two separate cables.

Just thinking about that..... would it be cheaper? Ok if the distance is not far but in many homes, the distance can be fairly long. Difference will be neglible though.

I get many installations where the boiler is located in an extension part of the house with no access to its roof space and the cable must be run externally from the attic over the 2nd floor. What cable do you use when run separately externally? I would normally use 7 core MYMJ for a 3 zone system and then use a relay if required or a boiler that uses 230v. Using 3 cables externally would be a bit of an eye sore.

shane0007

shane0007 wrote: »

Just thinking about that..... would it be cheaper? Ok if the distance is not far but in many homes, the distance can be fairly long. Difference will be neglible though.

I get many installations where the boiler is located in an extension part of the house with no access to its roof space and the cable must be run externally from the attic over the 2nd floor. What cable do you use when run separately externally? I would normally use 7 core MYMJ for a 3 zone system and then use a relay if required or a boiler that uses 230v. Using 3 cables externally would be a bit of an eye sore.

Call me old fashioned but a S-plan is a S-plan and I couldn't use a relay unless I had no other choice.

Admittedly I was lucky as working in London everything was S,Y or W plan, the switchable fused spur was in arms lenth of the boiler and there always was a 3a fuse fitted:) and I would have to wire a system the same. Personally I find the wiring standards here can be bad (which is a pet hate of mine), things are getting better but it has to be plumber/installer led.

I'd like to see more plumbers wiring their own heating systems and taking a steps towards being heating engineers which would include a uniform wiring design, ripping out all the cack and starting again, if we don't set the standard then it will always be cack.

No disrespect to sparks as some of my best friends are sparks, but heating engineers should be wiring heating systems, then I'd see less 7 foot room stats, stats above rads, beside the front door, boilers with no interlocks, boilers with no earths, boilers with no perminant lives and my all time favourite a roomstat a inch over a toaster:pac: