Plumbers NZ is New Zealand's largest online plumbing, gas and drainage resource. Plumbing exam help, plumbing news, directory and free quotes.
-
Hi guys. You may remember I was having trouble getting our solar water heating system sorted. A master plumber has been to have a look at it and among other criticisms, he says the air vent on the collector was installed incorrectly, parallel to the roof instead of being vertical, which would make it impossible for it to function correctly. If this is the case, then it is the root cause of all the other problems which arose from the tremendous shuddering the system endured while it was overheating. First of all, it shook out and displaced the sensor at the bottom of the HWC so the controller wasn't getting the info it needed. It also actually broke the wiring in the cable to the element causing sparking and melting of the insulation and the housing - yup THAT bad. And now it has shaken the 5 way valve connection into some sort of a fit.
However, this is a small town and the master plumber is unwilling to get involved in a tribunal hearing which is understandable. I just need to know one thing for sure, because the case rests on it - is it a fact that these vents have to be installed vertically or not? If so, what happens if they are installed at an angle? I'll attach photos so you can see what I'm talking about. Thanks
Doesn't seem to have been a successful post. I'll try again, one photo only this time. Looking at it, how else would you install it but just screw it in? So that's the way it would end up - sitting at an angle predetermined by the thing you screw it into?? Yes?
-
hi Corylus, still having problems i see!
(he says the air vent on the collector was installed incorrectly, parallel to the roof instead of being vertical) correct.
...
see this info it should tell you everything about the valve (A.A.V.) cheers
-
I'm really sorry to hear that it couldn't be resolved Corylus, but it looks like you have found your problem.
-
Thanks robbo
I'm looking at 5026 Yes?
And you are saying that it is correct that the valve must be installed vertically? What exactly happens inside it if it isn't? Remember I'm a little old lady and not a plumber, so be gentle. :D
It must surely be screwed into the manifold which has to lie at the same angle as the roof. So if the caleffi valve is screwed in at right angles to the manifold, it ain't going to be vertical huh? It is going to be parallel to the other side of the roof - which it is. There's nothing in the specs diagrams about where the air vent is fitted so I don't know what it looks like. Is there a bend of some sort to accommodate it so it can be vertical? Maybe the kit came without that bit. I'm finding it hard to believe that the plumber who put it in could have made such a mistake - he seemed to know what he was doing. The installer/owner/operator is something else altogether.
-
A piece of copper pipe bent to what ever angle is needed to make the AAV vertical.
-
Hi Badger. I hope life is treating you more kindly? I kept up with developments but not in the last week, being somewhat involved with my own problems. I thought I had it sussed, but my Master Plumber won't play. Which I understand completely. But I do need some sort of authoritative back up if I am to go to tribunal. Right now I just want the damn thing removed and my money back.
So if you were given a kit with a panel of vacuum tubes and a Caleffi air vent, you would know you needed to braise an appropriate elbow to ensure the air vent was vertical? What about the screw threads at either end? (don't laugh!! or rather feel free. I don't mind ;D) Or should the kit come with an already threaded extension which you can then bend as required?
Cheers
-
it doesnt have to be done with copper - it can be done using bras fittings to obtain the correct angle for the installation
use a female brass tee on the high end of manifold - usually 3/4"
3/4"x1/2" reducing bush either side
1/2"m&f elbow on the side the aav is going so you can get the right angle
other side of tee is your flow pipe to the heat store
will try and find photo
-
Thanks for that integrated. I think I understand that but a photo would be good if you can find it.
I take it there is general agreement that this thing needs to be vertical. But I'm a right one for knowing why. Maybe you noticed :D Who can tell me? Preferably translated into English - or even Physics. And don't say because it won't work if you don't. If I'm driven to take this guy to the cleaners I need to know I can win. So I'd like to be able to blind them with plumb. I don't imagine a referee on a tribunal will be an expert in plumbing but you never know.
Thanks guys. :)
-
A aav not mount vertical will just not work. that means it wont let air out.
so its as good as not having it there.
which means the air will remain in the closed loop circuit. And it will stop the circulating pump from working.
air will heat and want to go some where! hence the damage.
old school would have a vertical open vent off that highest point in the system so air could raise and vent.
plumbing 101. ::)
-
corylus, if you want the meat for the referee to chew on, find the brand name of the aav and get the installation specs. end of storey.
but. bits falling out of the cylinder??? that's not going to happen.
bits melting ?
I don't see how the aav will do that.
if your system over heats the control module has failed.
here is what would happen......
aav fails.....system cavitates ....circulating pump cant move water from the panels down to the hot water cylinder.
senor in the panel senses over heating.
system shuts off.
-
Corylus - if the plumber that came and gave the opinion charged you for that opinion then they should put it in writing. You have a couple of options - one if the Master Plumber has given an opinion but won't attend the tribunal, I believe you have a right to ask him to put the opinion in writing and if he won't then you can contact Master Plumbers Society head office in Wellington. Secondly if you believe the plumber that installed the unit has done so incorrectly, then you can report him to the Plumbers, Gasfitters and Drainlayers Board with all the information that you have. They will look in to it for you and investigate and if the person has not done it correctly then they could face a disciplinary hearing.
I presume you have gone back to the original installer and given them the opportunity to rectify? A tribunal will surely look if this has been done. Of course if they refuse to do so, then all bets are off and I would take them to the disputes tribunal and also put in a complaint. Most plumber, gasfitters and drainlayers are decent good guys, who do an honest days work for an honest days pay, but like every professional - there are some shisters out there - and it could be the person who did your solar was one of them.
-
Thanks everybody. Bowtieboy first. What you describe in your first reply is exactly what happens. The circuit between the bottom of the tank and the collector develops bubbles and I have to bleed the pump to keep the circuit going so I can get some hot water. Bear in mind that I have it in correction mode these days with the pressure down as far as it will go and the cold water turned right off at the 5 way valve. Regarding damage to the wiring/melting/cylinder - this was due to the tremendous shuddering that occurred because the system couldn't vent through the air vent. The HWC would be at 85° and the collector at 120° and steam bubbles were coming back down and into the HWC creating ructions. As I recall, the pump was still running. I honestly thought the HWC was going to burst out of its restraints. It was quite terrifying. What else would break the wire in the cable so that it sparked and burned itself out but an earthquake size shaking? And I couldn't get the installer to believe me. I'll attach the sound bite again in case you missed it last time. And that's only half of it. I missed the shrieking sound because my husband had put the hot tap on while I was firing up the Mac. Sensor in panel senses overheating and shuts off ? The controller never shuts the pump off these days. Not even when the sun goes down mate. It is totally stuffed now.
I have actually written to a contact at Caleffi and am waiting a reply.
Jaxcat. Thankyou. The master plumber came out of the kindness of his heart to see if he could help. He came 40km to do that and didn't charge a cent. I could not possibly expect him to get involved and I appreciate the fact that he came the way he did, in his own time, at his own expense. Regarding the installer - yes, I have been trying for months to get him to take responsibility for this installation. Years in fact. The overheating occurred within the first couple of months, as soon as the summer got into its stride (2010). I told him that it wasn't venting and he simply did not believe it. We live in a rural situation and he was never here to see it in action. It is him I have the beef with. He employed the plumber - not me. I thought they were a team. And I thought his business was a franchise, not a little small town business with the same name as the original one in Nelson. I still haven't figured that one out. To be fair, he does come and try to help, but I suspect he just doesn't have a grasp of the physics involved as a result of which he can't solve the problem and goes for finding a way to deal with the results of it instead - which can be downright dangerous. As in the present case. He wasn't able to work out the complexities of what seems to be a partial vacuum resulting from the pump being unable to access water from the bottom of the tank ( for some as yet undiscovered reason) , but just so I can get some hot water he wants to stick a valve in the header pipe - which is the only way steam has ever been able to get out at all. I didn't fancy having a bomb sitting in my airing cupboard waiting for the first hot day to go off, so I wouldn't let him do it./ I don't think our original plumber is a shyster at all. He's a decent man and I don't want trouble for him. But it has to be said - if that air vent isn't vertical, he's the one who did it. But he'd have put it right if he'd been given the chance - years ago. But because the installer never believed the vent wasn't working, he wasn't told. I'm not going to have the plumber crucified at this point years later, after all the subsequent damage has been done by not having it fixed. We all make mistakes, He'd have put it right if he'd known.
-
Forgot the sound bite. Sorry.
This time round . . .
-
I trust there is a temperature/ pressure relief valve in the system?
-
Hi Bowtieboy. Nope. It is an open system with a header pipe. No TPR. Just the air vent and a discharge pipe to the nearest gully trap - which was never expected to do anything. Both the plumber who put it in and the master plumber who came to suss the system, told me it was just something they had to do to get a tick in the right box when the council signs it off. Certainly it has never worked. I've recently MADE it work myself by tweaking the orange knob - but it's not something I'd care to do when the whole system is overheating and leaping about like a demented banshee. However, I got to hear what it does when it does goes off - and I've never heard it do that before. I'll attach the photo again to let you see it.
-
hi Corylus, some pics of my own system that i installed some years ago showing A.A.V. in correct position, if the pics are any use for an example of how it should be installed you are quite welcome to use them, i and i am sure all the guys here wish you well, cheers
-
Thank you robbo for the pics. I will certainly make use of them. And thanks everybody for the support. What would I do without you?
I'm a bit unhappy about my poor plumber in all this. I am certain he would have put it right had he been told. But I have to say, it's a bit of a worry that a safety device can be installed so that it can't work.
Haven't heard from Caleffi yet, but this will help. I'm not sure how to get the pics transferred off this site, but I guess I can work it out.
Thanks guys
-
hi Corylus, just click on the name orf the pic then save it to desktop or other place,cheers
-
Oh great. Thanks. I tried dragging it and got a lovely wee thumbnail. This is much better.
This is a marvellous website. Congratulations to whoever is responsible. I haven't begun to explore all it has to offer - never mind how to manage the bits and pieces. So now I have another one. Thanks robbo :-*
-
Robbo's all over it!
Good luck corylus!
-
Thanks integrated :)
-
Hi guys. Help me think this out? Just tell me where it's wrong.
If this AAV ain't working and the HWC is at 85° and the pump gets switched off by the controller, the water in the manifold is trapped? So it boils? And the steam can't vent. And as I understand it the conversion rate for water to steam, volumewise is 1660? That's some pressure up there then I imagine. And it continues to heat. Superheated steam? Must be a very well made manifold huh? It's a pity it didn't blow - he might have paid some attention to that. Instead it seems to have forced the steam against all its natural inclinations back down into the tank with resultant ructions as it collected up top trying to get out the narrow header pipe?
So. If the vent is actually working and steam can escape, the temp in the manifold shouldn't get above 100°? Is this your experience? What happens when the steam is all vented then? The manifold is empty? That must be interesting for the pump once it gets switched back on?
I see you are all having fun with your red cards. I wish I'd known there was such a thing . . . but I can see they are causing you aggro. You're not alone with this board and its antics you know. It seems to be widespread. If you knew the inside story of what goes on in the field of education - you wouldn't let your kids go to school. The people who make the decisions are not involved in the actual work, so their decisions tend to be utter nonsense (feckin' stupid as Badger might say). Same in hospitals these days. And as for being a soldier . . . well . . . you can forget about the bods up there in their safe offices having a clue what they are about.
-
hi Corylus, your situation can be explained but i don`t see the point. I have to say that from all of your correspondence the system has not been installed correctly and no amount of tweaking will fix it. It seems to me that rather than trying to sort it, it needs to be disconnected so as to be safe before it becomes a `BOMB` then the whole thing re-installed by someone who knows what they are doing, sorry to be so negative but you must be thinking enough is enough by now. So get someone to disconnect it and re-install the original system then look for someone who knows what they are doing to give some good advice, cheers
-
Hi robbo - yes that's the plan exactly. But I'm trying to put together my case and I need to know if my thinking is correct.
Your good advice needs money what I ain't got. Hence the need to screw some out of the guy who put it in. But I dont want to start something unless I can win. So I need to be right. I'm hoping to horrify the referee by explaining what this man has done by installing a safety vent that can't work. That sounds OK but it doesn't tell the story of what is happening up on that roof - which is pretty damn horrifying. And worse - what goes on in my airing cupboard if I let it - which is terrifying as well.
-
Corylus - pressure alters the boiling temp of water
under normal conditions the vented steam is replaced/made up by water
in your case tube manifold not venting so next place for it to go is path of least resistance - because you have open vent it allows excess pressure out of system - just in your case it has to overcome the volume and head of stored water before it can get there (to atmosphere)
-
hi Corylus, if the original installer will not fix it, you are entitled to have it fixed by another installer then send the account to the original installer, it`s really as simple as that, of course if he will not pay then you have a concrete case at the tribunal,cheers
-
Hmmmm robbo. I'll have to think about that. He DID offer to fix it - ages ago . His idea of fixing it was to put a valve in the header pipe to let me have hot water. When I declined to have a bomb in my kitchen he went into " Well then - I've done what I can - if you won't accept it - I can't help it." But things have moved on since then.
But thanks for that. I didn't know such a thing was possible. I didn't like the idea of having some innocent plumber being out of pocket while I tried to extract money I might never get out of this guy. I'm sure you get my drift!
integrated. Thanks for the corroboration. I have this picture in my head of a whole manifold of water being totally converted into steam and needing 1660 times more room than it has got. Obviously it doesn't do that otherwise the manifold would be kaput. It would be interesting to know at what point the pressure forces the steam down the flow pipe instead. Who knows. I'm not that keen on having it all in the HWC either!
But it is behaving itself very well at present. No danger of overheating. And other than the nuisance of having to mess about with the prv and the cold water lever, it is giving us more HW than it ever did before.
No news from Caleffi. I think I might ask too many awkward questions people don't have answers to . . . :D