vorkera flowmatic 20 - 80 RS problem.

[delta191]

Problem: my vorkera flowmatic 20/80 Rs has started to play up!

it has developed two main problems.

1.firstly, the water pressure drops to 0 bar everytime I use the central heating. I have to top it up to 1.5 bar with the water pressure tap under the boiler, which is very annoying eveytime I use the gch. this doesn't happen when the boiler is used for domestic hot water supply, IT ONLY happens when the central heating is used.
The pressure takes around 40 mins after the central heating has been switched off to drop to 0 Bar.
The pressure remains at 1.5 bar with no problem for days, even weeks if the GCH is never switched on.

2. the other problem (which is even more annoying)
when taking a shower, the hot water runs hot for a couple of minutes, then runs cold for a few minutes, then hot again, then cold, this cycle repeats all the time, so your stood in the shower waiting for the water to run hot again. my women is giving me serious grief about it!
I know when the water runs cold, the boiler isn't flaming up in the heat exchange. i can just see the pilot light lit.

I have had people out to the boiler before, I think they took out something, blew it and put it back in, and it worked.
(I cant think what it was called) - think it was a venturi or (means nothing probably)


I know the boiler is an older model and I have read previous posts on the forum and people say the boiler is a workhorse and gives reasonable service if its serviced regular.

I had someone service it last year when he change a diaphram.

could anyone give me an idea what maybe wrong?

I have someone coming to look at it tommorrow.

don't want him to scrap the boiler if it's nothing mega serious, is it worth repairing?

 

[ollski]

it needs a service, venturii cleaned and expansion vessel recharged / replaced.

 

[delta191]

I had someone take a look last week, he got a foot pump out of his van and pumped air into the expansion vessel (think thats what it was, it was right over the top of the boiler system because he was on my foot ladder). he told me to see how I went on with it overnight. the pressure dropped back down to zero bar within the hour.

does this mean I need to have someone replace the expansion vessel? how much should it cost? are they still available?

and whats this venturri part? does it get blocked every 12 months? what does it do? he charged me 120 quid to blow down it and put it back in.

I just want to know if I'm being mugged?

 

[DP]

All I can say is you have not got someone who knows their Flowmatic. You seem to be getting people who are trying to repair a fault without knowing where the defect lies.

Boiler has not been serviced or the pressure would not be dropping to zilch.

The HW isssue again should have been picked up at service stage (only if it was carried out as per the makers recomendations)

 

[tonybhoy]

Look mate your boiler is done,finished,finito.

It is at least 12 year old possibly 16.

Do yerself a favour and get a new one.

Throwing money at an old boiler such as this one is a complete waste of money.

 

[Agile]

Presumably Tony and Danny know each other and compete to replace and repair boilers respectively!

Tony

 

[DP]

Regret do not know Tony neither know how talented he is when he suggests a new steamer. Wonder if he knows his steamers just like he knows his Flowmatic.

OP, ball is in your court. Have come across several new boilers that I have had to walk away from but not a Flowmatic that could not be fixed (unless well rusted due to long term leaks).

When opting for a new boiler, you have to appreciate the system will need to be upgraded to BC requirements, chemically cleansed and treated also. All adds to the cost bottom line not looking too good then. A boiler can be changed in an afternoon (and often is) for it to fail very prematurely when it succumbs to system muck.

 

[bengasman]

Was service last year the first time in many years?
Pressure disappearing is simple, it is a leak. Sandwich bag and rubber band over prv pipe. See faq.
If you have been topping up often, system needs cleaning as well now, and checking for limescale build up.

 

[Agile]

Whilst the RPVs of course do leak, a common cause on this model is the AAV which is tucked up behind the pump and difficult to see let alone replace.

Tony

 

[delta191]

I've had someone take another look. He has sort of talked me into a new vokera boiler.

he said he can supply and fit the new vokera for around 850.00 which suprised me (all my friends say it will cost 1600.00 for a new combi)
the boiler is old, It was already in eight years ago when I moved in so I think it is time to ditch the workhorse!

He said he would price up a new expansion vessel but he could have to take the whole boiler off the wall to change it and that would cost dear in labour. He also pointed out that something else might fail after the repair, nothing lasts forever. so he's nearly sold the new vokera idea to me.

Are vokera condenser combi's any good? he hasn't told me what model yet. All my friends say get a valliant or wouster, vokera are rubbish!

I'm not sure whats the best option now, he said a wouster would be about 1250.00 and the vokera 850.00 to supply and fit.

or do I sit tight and see if the flowmatic can live another year with the new expansion vessel? how much will it cost to supply and fit it? I wouldn't go over 300.00

what would you do fella's? I'd be grateful to hear men of experience, especially Agile, he seems to know flowmatics! lol

 

[tonybhoy]

I've had someone take another look. He has sort of talked me into a new vokera boiler.

he said he can supply and fit the new vokera for around 850.00 which suprised me (all my friends say it will cost 1600.00 for a new combi)
the boiler is old, It was already in eight years ago when I moved in so I think it is time to ditch the workhorse!

He said he would price up a new expansion vessel but he could have to take the whole boiler off the wall to change it and that would cost dear in labour. He also pointed out that something else might fail after the repair, nothing lasts forever. so he's nearly sold the new vokera idea to me.

Are vokera condenser combi's any good? he hasn't told me what model yet. All my friends say get a valliant or wouster, vokera are rubbish!

I'm not sure whats the best option now, he said a wouster would be about 1250.00 and the vokera 850.00 to supply and fit.

or do I sit tight and see if the flowmatic can live another year with the new expansion vessel? how much will it cost to supply and fit it? I wouldn't go over 300.00

what would you do fella's? I'd be grateful to hear men of experience, especially Agile, he seems to know flowmatics! lol

850 notes is a great quote I would bite the guy's hand off.

A Vokera compact 29 HE will cost you £539 or a 24 £469 so the guy is hardly ripping the proverbial.

I fitted those boilers when they first came out ,installed a 24-96 RSE in my own house 15 years ago good boilers but they've had thier day.

And,the guy is bang on to replace the EV you have to take the boiler off the wall which amounts to about the same labour as fitting a new one.Some guys piggy back a new EV onto the system pipe-work at the boiler but frankly that is just buying you a bit of time before the one in the boiler rusts and leaks.

BTW a WB greenstar junior 28I comes in about £850 including the flue and time-clock.

 

[tonybhoy]

Presumably Tony and Danny know each other and compete to replace and repair boilers respectively!

Tony

Spending £120 on an old boiler is a complete waste of money!

You know as well as I do-least you should-just how old those boilers are and as sure as eggs are eggs some other major component will go in the not to distant future.

A fan for those boilers is near the £100 mark ex fitting as is the board.

Boilers are too cheap nowadays ,relatively speaking.

Expensive repairs to old ones is just not cost effective.

Anyway you just need to touch something on a boiler of that age and it is leak city.

The vent plug above the domestic heat ex will probably be all chewed up meaning you can't vent it once it has been drained down which means no hot water which means another part replace and on it goes.

 

[Nixt]

When your repairer inflated the expansion vessel its unlikely to have pressurised it because the flowmatic has no drain valve it's emptied through the PRV which springs back shut.

In order to inflate the vessel to 1 bar a drain point needs to be open (with boiler F/R closed) otherwise you are reading pressure in the boiler, not vessel pressure.

The diaphragm change is useless unless the diverter valve in front of the diaphragm manifold is also stripped and cleaned, shuttle replaced, pins/shafts greased with o-ring lube. The full service kits are still available.

PS This model ceased production in 1994.

 

[tonybhoy]

The diaphragm change is useless unless the diverter valve in front of the diaphragm manifold is also stripped and cleaned, shuttle replaced, pins/shafts greased with o-ring lube. The full service kits are still available.

PS This model ceased production in 1994.

I've done that whole strip down thing and it is a pure pig to do and 3 hours labour not to mention going to get the service kit and checking out the boiler initially.

I've also replaced EVs on Maxims and a Saber.

Even when there is plenty of room above the boiler they are still murder to get out.

BTW,I've been fitting Vokera compacts /Sabre condensers now for the over two years and have had very little problems.

Two Saber condensing HEXs(recouperators) out of about 60 odd.

Personally I think they are decent boilers.First started fitting them about 1989 or thereabouts,Vokera are very very popular here amongst RGIs.

 

[tonybhoy]

Whilst the RPVs of course do leak, a common cause on this model is the AAV which is tucked up behind the pump and difficult to see let alone replace.

Tony

Actually quite easy to get out all you do is loosen the top pump connection and the whole thing swings out.