CHANGING A RAVENHEAT CSI 85 DIVERTER VALVE?

[Hottub]

Hi,
Has anyone changed or know if its an easyish job to change a diverter valve on a condesing boiler?

[Agile]

The fact a boiler is condensing makes little difference to the work involved in changing a diverter valve.

I would be surprised if the diverter valve really needs to be changed! Why do you think it needs to be replaced?

Tony

[ChrisR]

Looks easy enough - but then it is a Ravenheat...

[HarrogateGas]

its not too badder job, bar one connection.

[Hottub]

I would be surprised if the diverter valve really needs to be changed! Why do you think it needs to be replaced?

Tony

Thanks everyone for the info, Tony I am guessing its the diverter valve because the central heating works fine, its just the hot water to the taps that plays up, I have to keep resetting the boiler then the hot water works again for a while until I have to reset again! Boiler has just been service by a corgi reg plumber and said all was well! However fault is now getting worse. Thanks Wayne

[ChrisR]

Check the microswitches on the end of the DV

[Hottub]

Check the microswitches on the end of the DV

Not sure how I would go about that?

[Agile]

Hottub wrote:

I would be surprised if the diverter valve really needs to be changed! Why do you think it needs to be replaced? Tony I have to keep resetting the boiler then the hot water works again for a while until I have to reset again!

If the boiler fires up when a tap is turned on then clearly the diverter is working.

This "resetting" sounds as if it may be an overheating or combustion related failure which is nothing to do with the diverter valve!

Tony

[Hottub]

I have to keep resetting the boiler then the hot water works again for a while until I have to reset again!

If the boiler fires up when a tap is turned on then clearly the diverter is working.

This "resetting" sounds as if it may be an overheating or combustion related failure which is nothing to do with the diverter valve!

Tony

If the boiler is tuned to water only it never runs hot water to the tape it only seems to work when heating and water are both on?
Many thanks Wayne

[ChrisR]

Check the microswitches on the end of the DV

If the switch isn't getting operated you'd get no hot water unless you have the CH on, which is what you've got.

If the DV/switch was sticking in HW position, I wouldn't be surprised if the boiler overheated.

So intermittent "mucking about" could all come down to the DV.

When the hw is turned on the pin should come right out smartly and press the switch fully, and go back equally smartly when the tap goes off.
The switch contacts should make clean open/closed circuits.

Quick to check if you know how - otherwise you need an engineer.

[Hottub]

[quote="ChrisR"]Check the microswitches on the end of the DV

If the switch isn't getting operated you'd get no hot water unless you have the CH on, which is what you've got.

If the DV/switch was sticking in HW position, I wouldn't be surprised if the boiler overheated.

So intermittent "mucking about" could all come down to the DV.

When the hw is turned on the pin should come right out smartly and press the switch fully, and go back equally smartly when the tap goes off.
The switch contacts should make clean open/closed circuits.

Quick to check if you know how - otherwise you need an engineer.

O.k. Many many thanks for your help/advise ill try and check the pin operation, might try and change the diverter valve tonight if I get stuck, ill have to call the gorgi guy back!
Many thanks everyone!

[Hottub]

I was going to change the diverter valve last night and turned off all the valves etc, I then unscrewed the bleed nut and very high pressured water shoot out so I quickly put the bleed nut back on!

Does anybody know if the water should come out this pressurised or maybe there’s something I haven’t turned off?

Thanks Wayne

[ollski]

The water will still be sat in the boiler and in the pipes at the system pressure. You need to isolate it as you have done and then drain the boiler itself making sure the aav is open also open all your hot taps so the water can run out when you undo the connections and let the air in. That will minimise the water you will come across but still make sure all the electrics are well covered.

[Paul Barker]

But has been said you might not need a new diverter valve. You might need a thermister or a microswitch, or at worst a diaphragm. If you need to ask these questions but without the ability to describe the situation more fully, you are demonstrating that your conclusion isn't intelligently arrived at. It would be down to luck now as to whether you have plumbed for the right part. It is one valid way to fix a boiler, to just throw parts at it. Works for the spotty youths working for a once respected national gas supplier.

[Hottub]

O.k. thanks, I’ve now changed the diverter valve and heating and hot water working fine, did take the old diverter valve apart and all looked o.k. in there, the diaphragm wasn’t split but obviously something was wrong!
Once again many thanks for all your knowledge/help!

Wayne