While the radiators water can be dirty and is not a health rish unless you drink it, it is used to carry heat that heats the cold water with the sardine stack acting as a separetor. Quite a common design. There are other ways to get the same result
Boiler schematic explanation
- Thread starter Alison556
- Start date
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Is yours the earlier design with three lights on the front or the later one with two lights?
You have hit on a design fault that occurs with the earlier models but the issue was addressed with the later ones.
It was cured by introducing a pump over-run after a hot water demand has ceased which dumps the primary hot water from the plate heat exchanger into the heating system.
PS I'm not normally this clever but I just got back from a Ravenheat training course.
You have hit on a design fault that occurs with the earlier models but the issue was addressed with the later ones.
It was cured by introducing a pump over-run after a hot water demand has ceased which dumps the primary hot water from the plate heat exchanger into the heating system.
PS I'm not normally this clever but I just got back from a Ravenheat training course.
It must be a later one - it's got two lights - a green on/off one and the red overheat light.
It's still shown on Ravenheat's website and we've only had it two years in January.
So am I back to the Ravenheat man being right that it shouldn't be doing it and the gas man, although being right, is wrong about this boiler?
I think I need a drink!
I've just had another look at Ravenheat's website again and notice that they do a CSI 85B T and a CSI 85 AAA T boiler - dunno which one mine is cos they both look the same and the installation manual doesn't say which one it is either.
Whatever one it is, should it still have this problem?
Here's the schematic for it anyway......does it have what you're talking about in it?
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That schematic's kinda wrong though, because it's never in the mode they've shown, which would be having a go at heating and hot water at the same time. HW always takes priority, but if it's off, it's off.
Try this:
Shown with the heating on, the green bits shouldn't be getting hot. If they are, the diverter valve is letting-by to the HW heat exchanger.
Try this:
Shown with the heating on, the green bits shouldn't be getting hot. If they are, the diverter valve is letting-by to the HW heat exchanger.
Geez and that's off Ravenheat's website! Doesn't give you much faith in their boilers if they've not even got the schematic right!!!
But does it have this pump over-run that slugbabydotcom was talking about? If it does, then mine ain't working!
I know it sounds like a silly, trivial little thing complaining about too hot water, but I'm terrified somebody (kids or eldery relatives) gets badly scalded when they turn the hot tap on when the central heating is on.
But does it have this pump over-run that slugbabydotcom was talking about? If it does, then mine ain't working!
I know it sounds like a silly, trivial little thing complaining about too hot water, but I'm terrified somebody (kids or eldery relatives) gets badly scalded when they turn the hot tap on when the central heating is on.
The problem is knowing when they actually sorted this out. John Wilson, thats the guy at Ravenheat you need to talk to, didn't specify exactly when this DHW over-run was introduced. Although I was left with the impression that the Mk2 version had it, there is a chance that it is just on the latest versions. All manufacturers have to keep up with a constantly changing regime of safety and manufacturing requirements.
The main difference between the earlier Mk1 and the Mk2 is that the ignition circuitry has been moved to the main PCB
They do change things from time to time and there is a disclaimer to this effect on the front of their MI's
If you cant get to talk to JW email me your serial number and I will give him a ring.
The main difference between the earlier Mk1 and the Mk2 is that the ignition circuitry has been moved to the main PCB
They do change things from time to time and there is a disclaimer to this effect on the front of their MI's
If you cant get to talk to JW email me your serial number and I will give him a ring.
Would he actually speak to me about it?
When I phoned them, I went through to General Enquiries cos the only technical option was for being Corgi registered (which I'm not). I explained what I was wanting to the girl and got a sharp intake of breath from her. She put me through to some guy who again did the sharp intake of breath followed by a stunned silence cos I'm not Corgi registered and was asking a technical question!
Geez, is being Corgi registered a secret society?
Where do ya want me to e-mail the serial number to (that's if I can translate the hieroglyphics that pass as writing on the log book)?
When I phoned them, I went through to General Enquiries cos the only technical option was for being Corgi registered (which I'm not). I explained what I was wanting to the girl and got a sharp intake of breath from her. She put me through to some guy who again did the sharp intake of breath followed by a stunned silence cos I'm not Corgi registered and was asking a technical question!
Geez, is being Corgi registered a secret society?
Where do ya want me to e-mail the serial number to (that's if I can translate the hieroglyphics that pass as writing on the log book)?
You can try and you might stand a chance if you ask for him by name and mention this forum when you speak to him.
If I have the serial number I can call him and try and get to the bottom of it for you.
Email it to the address in my profile. I'm glad you have the documentation because there are 2 places where you can find it inside the cover. One is on the left at the back and usually obscured by the side casing. the other is right at the back on the right, low down and facing to the left. Virtually unreadable unless you have a camera phone and can upload the pic onto a computer.
With this code they can tell the precise model and where it was sold.
EDIT:-
I might have sussed it here!
PCB numbers available for CSI's
0012CIR05005/0 Mk1
0012CIR05005/1 Mk2
0012CIR05005/2 Mk2
I'm betting yours has the /1 PCB and the over-run feature is on the /2 version.
If I have the serial number I can call him and try and get to the bottom of it for you.
Email it to the address in my profile. I'm glad you have the documentation because there are 2 places where you can find it inside the cover. One is on the left at the back and usually obscured by the side casing. the other is right at the back on the right, low down and facing to the left. Virtually unreadable unless you have a camera phone and can upload the pic onto a computer.
With this code they can tell the precise model and where it was sold.
EDIT:-
I might have sussed it here!
PCB numbers available for CSI's
0012CIR05005/0 Mk1
0012CIR05005/1 Mk2
0012CIR05005/2 Mk2
I'm betting yours has the /1 PCB and the over-run feature is on the /2 version.
Leave it 4 now. I edited my last post and think I have sussed it. I will contact him and ask you again for the number only if necessary.
It's starting to rival War and Peace!!!
I'm determined to get to the bottom of this. I'm sick of being fobbed of by stroppy gas men! I must be well unlucky. What bugs me the most is that they think cos I'm a girl I'm flippin clueless. I might not understand the intricacies of a boiler, but explain something to me and I pick it up no problem.
I ain't no silly useless girl - I do all the work round the house - inside and out (just given myself a crash course in pointing!! ) and I've done most of my joinery and plumbing work myself - not so good with electrics though - got this fear about plugging myself into the national grid!!!
There's nothing I can't do without my trusty DIY book and the internet!
I'm determined to get to the bottom of this. I'm sick of being fobbed of by stroppy gas men! I must be well unlucky. What bugs me the most is that they think cos I'm a girl I'm flippin clueless. I might not understand the intricacies of a boiler, but explain something to me and I pick it up no problem.
I ain't no silly useless girl - I do all the work round the house - inside and out (just given myself a crash course in pointing!!
) and I've done most of my joinery and plumbing work myself - not so good with electrics though - got this fear about plugging myself into the national grid!!!There's nothing I can't do without my trusty DIY book and the internet!
Just kicked my poor lonely brain cell into gear.
The problem comes about when the hot water is turned off.
The diverter valve closes and the hot system water in the plate heat exchanger is sat there chucking all its heat into the domestic side of the Plate Heat Exchanger. This causes the domestic water to get rather hotter than it should be and a PHE full of overheated domestic water will be in the pipework if the tap is re-opened before the PHE cools down.
A giannoni diverter valve closes the diverter section when the tap goes off and takes the pump out of circuit from the PHE.
Simply leaving it running during the CH anti cycle time cannot clear this hot system water from the PHE
Only if the boiler is fitted with a mechanically operated diverter will it have the ability to dump this excess heat into the system!
So to sum it up this is a problem with older Ravenheats and as a lot of boilers of that era work the same way then they must have the same problem too.
To reduce this effect and risk of scalding try to avoid drawing hot water in short bursts. Consider blending valve/s if you still consider this to be a serious risk
Apologies for not hitting the nail on the head first time round but I knew the answer was in between my ears somewhere.
The problem comes about when the hot water is turned off.
The diverter valve closes and the hot system water in the plate heat exchanger is sat there chucking all its heat into the domestic side of the Plate Heat Exchanger. This causes the domestic water to get rather hotter than it should be and a PHE full of overheated domestic water will be in the pipework if the tap is re-opened before the PHE cools down.
A giannoni diverter valve closes the diverter section when the tap goes off and takes the pump out of circuit from the PHE.
Simply leaving it running during the CH anti cycle time cannot clear this hot system water from the PHE
Only if the boiler is fitted with a mechanically operated diverter will it have the ability to dump this excess heat into the system!
So to sum it up this is a problem with older Ravenheats and as a lot of boilers of that era work the same way then they must have the same problem too.
To reduce this effect and risk of scalding try to avoid drawing hot water in short bursts. Consider blending valve/s if you still consider this to be a serious risk
Apologies for not hitting the nail on the head first time round but I knew the answer was in between my ears somewhere.
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