Any GS registered person up for a boiler challenge in S. Cumbria ?

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First off ...
If your attitude to thermal stores is to suggest ripping it out and replacing with a combi - don't reply.
If you can't cope with uncommon setups - don't reply.
If you don't like working with customers who know enough not to be fobbed off with bull**** - don't reply.
If you are the sort who will simply say "that's really old, can't be fixed" - don't reply.

If you're still reading, then here's my problems ...

I have a rental flat with a very old boiler (Vokera Excel 80), yes I know it's old, yes I know a new one would be a good idea - but until someone comes up with an acceptable flue routing for a new one, I'm a bit stuck. Ten years ago I fitted a thermal store, moved the DHW connections to the store, with the boiler directly heating the store, and the heating running from the store with a modulating pump. It's worked fine for ten years.
A few months ago I found during a visit that it's kettling. I have a service plan with a local outfit, and they spent 4 days on it (not 4 full days, but they were there for 4 days). They've replaced the pump, rebuilt the flow sensor valve, checked all the pipework, drained the system (despite written instructions not to), refilled it, pressurised it (yes, pressurised a 10 year old open vent store :eek:), added inhibitor (they won't say what or how much, so I don't know if they added enough* or what to use for topping up), and finally added boiler silencer and left it saying it can take a couple of weeks to work. Now they are saying that it's bound to be doing it because of it's age and they can't fix it.


This week was annual service and safety checks time - it's still kettling but not as much as it used to.

So the short term problem is fixing the kettling. If there's someone reasonably local (Furness area) that would be interested in looking at it, then I'd be interested - contact me via PM. And before anyone chirps up, yes I'm prepared to pay a reasonable call-out charge. And yes I can accept if you can't fix it - as long as you don't try and fob me off with bull.

* It seems plenty of people are incapable of reading instructions and working out the correct dose, so I have no confidence that they added enough for the size of the system.


The second issue is the age of the boiler - it really is well past it's replace by date, and that was a factor in fitting the thermal store ten years ago. But the current flue location, while technically allowed, was not really good practice when it was installed - and it's not acceptable now for a new steamer. I have some ideas, but most installers simply tell me what they want to do (typically something that's unacceptable for various reasons, but chosen because they can't be arsed to engage any brain cells) and aren't even prepared to discuss alternatives.
So the first person to come up with an acceptable proposal gets the job. I have money set aside for it.

PM me if interested.
 
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DP

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The second issue is the age of the boiler - it really is well past it's replace by date, and that was a factor in fitting the thermal store ten years ago. But the current flue location, while technically allowed, was not reall

Look after plenty excels. Full strip down and then rebuild, it is like new
A4316670-55FE-47FA-B74B-B745E2BD5790.jpeg


One of the vokeras that is previous model to yours. This one made in ‘91, not pushed a new boiler!!!!
Excel is all brass components, tender care it comes out shiny. Only issue will be the plastic facia will be brittle.

When you say system is open vented, you mean the boiler is running open vented too?

Not surprised the boiler is kettling. Put a new heat exchanger in the boiler, a magnetic filter and ensure inhibitor is the correct dosage
 
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Yes, boiler is running open-vent, and with position of F&E tank it'll have about 0.4 bar pressure in it. Flow rate should be fine, just something like 8m of 22mm copper pipe (total run, counting F&R separately) and a TMV between it and the store - so less resistance than driving a loop of rads.
You may have sensed that I'm not overly impressed with the outfit I use - but they fit into that sweet spot where they are small enough to be able to shout at the boss when needed, but big enough not to be turning round and saying "sorry mate, I'm booked up till a week on Tuesday".
Yeah, the fascia is getting a little tired - during the last works I see they've snapped off one of the hinges so one side flaps around now. The thermometer stopped working some time ago - my guess would be that the capillary has cracked. But otherwise, it's still going strong apart from the kettling. I did note that they'd not said anything about descaling or replacing the heat exchanger - I believe scale is one of the main causes of kettling.
 

DP

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Yes, boiler is running open-vent, and with position of F&E tank it'll have about 0.4 bar pressure in it. Flow rate should be fine, just something like 8m of 22mm copper pipe (total run, counting F&R separately) and a TMV between it and the store - so less resistance than driving a loop of rads.
You may have sensed that I'm not overly impressed with the outfit I use - but they fit into that sweet spot where they are small enough to be able to shout at the boss when needed, but big enough not to be turning round and saying "sorry mate, I'm booked up till a week on Tuesday".
Yeah, the fascia is getting a little tired - during the last works I see they've snapped off one of the hinges so one side flaps around now. The thermometer stopped working some time ago - my guess would be that the capillary has cracked. But otherwise, it's still going strong apart from the kettling. I did note that they'd not said anything about descaling or replacing the heat exchanger - I believe scale is one of the main causes of kettling.
Issue here is more likely large body of water in the thermal store plus the radiators will initially lead to higher corrosion due to air in the water till the oxygen is used up, to then continuous further air ingress during expansion and contraction in the header cistern. Lack of sufficient corrosion inhibitor and limescale thrown in will not be taking any prisoners as far as embattled heat exchanger is concerned.

If you were in Glasgow, would then offer my services.
 
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And I'd take you up on that.
I phoned them earlier about replacing the heat exchanger, the person needed to make that decision is out of the office till the middle of next week.
A number of times I've "questioned the competence" of their people - ignoring the heat exchanger as a possibility is just one more reason. TBH, given their "get out of our way, we know what we're doing" attitude I'd decided to give them a bit more rope to make a noose with - otherwise I might have dropped hints to them earlier. Years ago, when it was still used as a combi, they were there multiple times and couldn't diagnose a failed microswitch (why do they design boilers to that any leaks go into electrical items :rolleyes:) - I had to diagnose it for them and tell them what to replace :whistle:
But given the problems of finding someone else who isn't even worse ...
 
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OK, an update ...

Had an appointment last week - with the usual instruction to call me when setting off so I can go up with the keys. I was getting to the point of ringing their office to see if they were still coming when ... they rang me. "We've got the job sheet back, he said he went but there wasn't anyone there" - to which I replied, "there wouldn't be as no-one rang me to say they were on the way". She put me on hold, but the guy was already tied up with another job - so there's another half day of leave from my day job wasted.
Re booked for this morning. Did get a phone call, and he did turn up. And as usual I had to sit there providing basic information that's all in the manual they've been given several times - "the controls are upstairs aren't they ?", "no, they are all down here"; "I'll need to go upstairs to turn the water off" (I think he was thinking he'd need to drain the store), "no, there's isolating valves on the store"; <as he goes to the filter with his bucket> "that doesn't drain the boiler, it's on the heating circuit, there's a drain cock <points> there"; ... It's not like it's a complicated system - it's just a cylinder, a loop to the boiler, and a loop for the heating - and they have a manual with a labelled photo, electrical and hydraulic schematics. It just seems that none of them can cope with that, and it's clear that few of them are even aware of the existence of the manual.

EDIT: In case the above rant gives the wrong impression, I was quite happy with the guy's work apart from the clear issue that he didn't seem to "get" a thermal store.

But actually swapping the HE was a simple job, and afterwards it's ... nice and quiet, quelle surprise :rolleyes:

I think I'll leave it a day or two when I might be able to better articulate my views to them in a polite manner, and ask them why as supposedly competent people, not one of them ever said anything whatsoever about the possibility of it being the heat exchanger.

Oh yes, I nearly forgot but remembered just before he left. "Did they send you with any inhibitor ?", which they had - so popped upstairs to put it in the F&E tank which has magically lost it's lid. I can't prove it, but I'm pretty sure one of their engineers will have taken it off and put it to one side, and it's either buried in the current tenant's stuff, or gone with the previous tenant's clean out.
 
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Yes, are you trying to suggest something ? Or are you one of those who think it's reasonable to let trades people do stupid things (like drain the thermal store when there's isolating valves and a drain facility for just the boiler loop) with your property ?
 
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TBF, it’s not one of the best starts to a request for help post that I’ve seen…..
 
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Look after plenty excels. Full strip down and then rebuild, it is like new
View attachment 236677

One of the vokeras that is previous model to yours. This one made in ‘91, not pushed a new boiler!!!!
Excel is all brass components, tender care it comes out shiny. Only issue will be the plastic facia will be brittle.

When you say system is open vented, you mean the boiler is running open vented too?

Not surprised the boiler is kettling. Put a new heat exchanger in the boiler, a magnetic filter and ensure inhibitor is the correct dosage
Out of curiosity, am I right thinking that Vokera does not have a modulating burner, too old? So turndown is done by manually adjusting the burner pressure.
 
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Out of curiosity, am I right thinking that Vokera does not have a modulating burner, too old? So turndown is done by manually adjusting the burner pressure.
No the OP say he has a Vokera Excell, these come in two models, Standing pilot , and electronic ignition, both have modulating gas valves, the max CH output (range rating) can be manually set on the boilers pcb, but yes the answer to your question is yes they do modulate , it is not the burner that modulates (it never is) it is the gas valve that modulates, condensing appliances mainly adjust the fan speed and this in turn modulates the gas valve, on older boilers it is done via a modulating regulator on the gas valve, that is electronically adjusted via the thermistors and boilers PCB
 
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No the OP say he has a Vokera Excell, these come in two models, Standing pilot , and electronic ignition, both have modulating gas valves, the max CH output (range rating) can be manually set on the boilers pcb, but yes the answer to your question is yes they do modulate , it is not the burner that modulates (it never is) it is the gas valve that modulates, condensing appliances mainly adjust the fan speed and this in turn modulates the gas valve, on older boilers it is done via a modulating regulator on the gas valve, that is electronically adjusted via the thermistors and boilers PCB
Thanks for that. I hadn't thought modulating boilers were available that far back, but clearly I was wrong.

I appreciate modulation is by adjusting the gas valve, thereby varying the pressure into the burner. On my 22-year old (non-modulating) boiler the burner pressure is adjustable on the gas valve with a screwdriver. On the nameplate posted in #2 the max and min outputs correspond pretty well with the max and min pressures.
 
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Thanks for that. I hadn't thought modulating boilers were available that far back, but clearly I was wrong.

I appreciate modulation is by adjusting the gas valve, thereby varying the pressure into the burner. On my 22-year old (non-modulating) boiler the burner pressure is adjustable on the gas valve with a screwdriver. On the nameplate posted in #2 the max and min outputs correspond pretty well with the max and min pressures.
yes even with a modulating gas valve you have to set the Max and Min burner pressures on the gas valve, what you have is called a range rated boiler where you set the max pressure on the gas valve, but a combi needs a lot more burner pressure when running HW than when running CH, and that pic in #2 is a Vokera RS Flowmatic, the OP has a Vokera Excell, they are not the same boiler, havent a clue why that pic is there to be honest
 
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TBF, it’s not one of the best starts to a request for help post that I’ve seen….
In what way ? I can understand that some might be put off by the list of "If you ..." suggestions, but given how some people are in this part of the forum I thought it might be as well to get those out of the way. And yes, I've seen comments in the past that would lead me to expect "solutions" offered in all four categories. :rolleyes:
What is a thermal store?
Serious question, or a joke ?
... and that pic in #2 is a Vokera RS Flowmatic, the OP has a Vokera Excell, they are not the same boiler, havent a clue why that pic is there to be honest
DP put it in to show that old models can be kept going.
 
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