Ravenheat CSI85 - Stronger Earth???

[Woolf]

Hi,

Here's a tale about a new Ravenheat CSI85 condensing boiler, installed just 5 months ago. (It replaced the same model which we'd had since 2004 without problems until it needed a new condensing heat exchanger. I wanted to keep it and have it repaired - but I was outvoted!)

Within half an hour of the new boiler being fitted, we couldn't get hot water when the central heating was on. Two days later, (under guarantee, obviously) a new circuit board was fitted, but as soon as the engineer had gone - same problem. A couple of days later the same engineer fitted 'a stronger earth,' and (aren’t we lucky) we could get hot water and central heating for our money. The boiler made quite an electrical buzz though - we didn't have that with the old one.

So here's my question at this stage of a sorry tale. The concept of 'a stronger earth' seems to puzzle some engineers. Is it a wind up? Is 'a stronger earth' the builder's equivalent of 'the wrong type of walls'?

Many thanks for your help.

 

[JohnD]

the required sizes for main bonding cables is now 10mm, it used to be 6mm, and before that was any sort of fence-wire. Perhaps your engineer upgraded the wire to current standards or added 4mm supplementary bonding to the boiler pipes. However the presence and size will improve safety, it will have no effect on the operation of your boiler.

 

[bengasman]

A STRONGER earth??? If the new bonding made any difference, it means that the electrical supply to the boiler is highly suspect. The cpc in the cable to should be more than enough to make the boiler work accurately.
It may be that your electrical installation has a dodgy earth and is now using the gas or water pipes for earth. This is dangerous to say the least. I strongly recommend that you get an engineer in from a company that specialises in electrical TESTING, rather than somebody who will test, repair, install and extend. The former might be slightly dearer for the test itself, but as they have no incentive to sell you electrical work, you can expect a fully unbiased opinion.
Did you get a minor works certificate or a notification letter from the council? A commissioning report?

 

[Woolf]

Hi,

Thanks for your replies JohnD and bengasman - and the benefit of your expertise. I got an Installation, Commissioning and Service Log Book after the installation, which was done by a Corgi registered company.

 

[simond]

The Benchmark form you refer to has no relevence to the electrical safety of the installation. If a boiler is fitted in a kitchen or bathroom it is notifiable, to an electrical body and building control.

Having spent lots of time and money on training and test gear I find ourselves in the wilderness; it seems no-one else in my area does it (or even mentions their obligation under building regs) and if I include it we are usually considered uncompetitive. Ho Hum.

The stronger earth -or any earth -could affect the ignition sequence on HW and CH so you can rule this out as balony.

Incidentally, 10mm earth bonding is not required for T-T installations, are you qualified to offer electrical advice, JohnD?

 

[Woolf]

Hi, thank you very much for your reply simond. It's very enlightening and I'm obviously going to have to follow up the question of electrics with the original installers. I'm sorry that your safety expertise isn't given the credit or custom it deserves.

In the meantime, here's some more of the story...

The boiler worked until a couple of weeks ago, when the red flashing 'overheat' light started to come on, and the boiler to switch itself off. It can usually be switched on again by resetting, sometimes it needs a while to cool down first. The 'stronger earth' engineer came again and he seemed stumped. He decided that the pressure needed reducing (it had always run at over 2 bars) and I think he did this via the emergency safety valve - the gauge now reads one and a half bars. The boiler worked for an hour or so after he'd gone then started to cut out again (with flashing warning light).

Yesterday we had a different engineer and he fitted a new pump. The boiler worked for a while after he'd gone (sounding familiar?) then started to cut out again (with flashing warning light). Discussing the problem earlier, he said that other possible reasons for overheating were a blockage on the system (installed Autumn 2004) or a problem with the burners. (Incidentally, we've never had this boiler on a particularly high heat, although the cut-outs usually happen in the evening when the house is warmer: the boiler is in the kitchen, same place as the old one.) All the radiators are working well except the second on the system (a small double in the bathroom) which - only since the pressure was reduced by the engineer - gets hot at the bottom, but only warm at the top. I guess that this now needs bleeding.

An engineer is coming again on Monday. Can anyone shed more light on this for me please…!

Many thanks for your opinion.

 

[Woolf]

Hi all,

Well our engineer came today. He fitted another new circuit board, a new potentiometer, a new overheat thermostat and a new heating sensor. I told him that the problem only occurred when the room was warm in the evening from cooking and he said no - the boiler can't take air from the room, so room temperature doesn't make any difference. When he'd finished, I asked him to wait while we got the room up to temperature to test what we knew, but he didn't have time - he had other calls to make.

I hoped that I would be able to do an update here saying that the boiler was cured. But it isn't. It's tea time, we're cooking, the warning light has just started to flash and the boiler has cut out again. So no heating and no hot water. I'm hoping that it can be reset again when the room cools down.

Hope that this information may be of use to anyone thinking of buying the same boiler.

 

[Woolf]

Nope, it wouldn't reset.

So we had heating and hot water, albeit intermittently, but now after 2 hours worth of Ravenheat repairs, we've got nothing...

Perhaps you'll see me on Watchdog!

Cheerio!

 

[bengasman]

Methinks even ravenheat would guarantee their repairs longer than 2 hours. It is not your responsibility to tell the engineer how to fix the problem, and you did inform him that it is an intermittent problem.
If the work did not solve the problem, they should either reimburse you or send another engineer to repair the fault. Just call them and ask them to rectify

 

[Woolf]

Thanks bengasman - that's very true. It's back to intermittent now (although presently off We could do with a little icy blue-faced emoticon here, couldn't we?).

I've got an engineer coming on Thursday….

 

[D_Hailsham]

Here's a tale about a new Ravenheat CSI85 condensing boiler, installed just 5 months ago. (It replaced the same model which we'd had since 2004 without problems until it needed a new condensing heat exchanger.

Do you mean that the heat exchanger of the old boiler only lasted three years? Or that you have only been in the house for three years and the boiler is older?

If the first, I would have learnt my lesson and not installed the same brand of boiler again. In my opinion (dangerous ), if a heat exchanger, or any other part for that matter, only lasts three years there is a good case for arguing that the component is 'not of satisfactory quality and not fit for purpose' (Sale of Goods Act 1979 as amended).

Take a look at:

Sale and Supply of Goods to Consumers , Guide for Domestic Plumbing and Heating Industry

It is very informative and well worth the read, by Trade as well as Customers.

 

[Slugbabydotcom]

It's tea time, we're cooking, the warning light has just started to flash and the boiler has cut out again.

Theres your common denominator Temperature or humidity sensitive is the question.

Have a take away and see what happens

You don't have your kettle under your boiler do you?

 

[JohnD]

is it a gas cooker?

 

[Woolf]

Here's a tale about a new Ravenheat CSI85 condensing boiler, installed just 5 months ago. (It replaced the same model which we'd had since 2004 without problems until it needed a new condensing heat exchanger.

Do you mean that the heat exchanger of the old boiler only lasted three years? Or that you have only been in the house for three years and the boiler is older?

If the first, I would have learnt my lesson and not installed the same brand of boiler again. In my opinion (dangerous ), if a heat exchanger, or any other part for that matter, only lasts three years there is a good case for arguing that the component is 'not of satisfactory quality and not fit for purpose' (Sale of Goods Act 1979 as amended).

Take a look at:

Sale and Supply of Goods to Consumers , Guide for Domestic Plumbing and Heating Industry

It is very informative and well worth the read, by Trade as well as
Customers.

Hi D Hailsham,

Thanks for your reply. Yes, it lasted 3 years from new. We didn't have a single problem in those years, but when the heat exchanger started to go, there was a single incident of the overheat light coming on and the boiler cutting out - just that once. It restarted by resetting straight away.

The engineer who came to repair the boiler (out of guarantee) quoted (if I remember correctly): £350 for heat exchanger, and future grief on account of the cut out problem. So - disadvantage of keeping old boiler - we'd be throwing money at it in unknown quantities. The advantages of a new one - it would be under guarantee, then we could take out a service contract thereby saving money on endless repairs. We'd have 3 years of stress free boiler ownership (lol). And we could have the new boiler fitted in summer, so no cold, no hassle. Perhaps our engineer should have been on the stage, I don't know. Could the phrase 'lambs to the slaughter' appropriate here?

Within minutes of the new boiler being installed, of course...disaster as described in the messages above, with much stress - (and now happening in winter), much hassle, much cold, some buying of electric oil-filled radiator, much arranging for engineers to come, much waiting in, and much trying to find remedy (since it seems to be beyond their ken)!

I honestly did not want this boiler...I conceded (to OH) for an easy life....shows you how wrong you can be...

Thanks for the link. It looks like a very good site and although it's too late for the 'old' boiler, it may be useful now....

 

[Woolf]

It's tea time, we're cooking, the warning light has just started to flash and the boiler has cut out again.

Theres your common denominator Temperature or humidity sensitive is the question.

Have a take away and see what happens

You don't have your kettle under your boiler do you?

Or sandwiches Slugbabydotcom?

Thanks for your replies Slugbabydotcom and JohnD. Our engineer denies that anything going on in the kitchen would affect the boiler! We do have a kettle about three feet away, and a gas hob. The boiler is near a double sink too although we always have a big window open when we're cooking to keep steam to a minimum.

But we had the same model boiler in the exactly the same place for 3 years without problems (except for the death knell described above.)

Yesterday though, I spoke to someone who suggested that the problem may occur because when our house gets too warm, we turn down the radiator thermostats. Aaahhh - so the overheat cut out could kick in because of low flow pressure (or something along those lines)??? To test this, today I left all radiator thermostats on full and controlled room temperature by turning down the heat on the boiler instead.

And despite the heat of cooking...there was no cut out. The boiler stayed on. So perhaps there is something in this theory?

I hope that I find out later today....