Will it ever end?? Ravenheat Hot Water Problem!!! pls read

[Amy Carter]

Dear All,

I am becoming somewhat familiar to this site, and after spending almost £300 on parts for my boiler i'm becoming accustomed to the idea of becoming a Corgi Engineer!!!

Ok, i have a Ravenheat RFS820/20T Combi boiler, it would take me ages to explain everythin but so far the DV, PCB Thermocouplin and Circulation Pump have been replaced.... PHEW!!!

Now though, when I call for hot water, regardless of the flow rate the boiler starts "Kettling" and the water runs Hot and Cold. Please can anyone help, what could be the cause now??

Kindest Regards

Amy

 

[ChrisR]

Sludge or scale in the heat exchanger, or thermostat(s)/thermistor(s).

Kettling indicates boiler scale, so the easiest to try would be a Boiler Descaler, which you can just squirt in through the filling loop. Then run a bath or 3 to circulate it round the boiler (not diluting it into the rads)

Are you in a very hard water area?

 

[Amy Carter]

Yes we are in a hard water area....
thanks for your advice...

Amy

 

[Agile]

It could also be because the pump is not running during hot water delivery!

Although you list all these parts you should be aware that most of those parts were not needed. The PCB particularly as it virtually never fails. I have never ever replaced one!

I had a nice Indian meal a couple of weeks ago almost under the northern inner ring road bridge in Norwich.

Tony

 

[Amy Carter]

The PCB did need replacing as only 110 volts were running through it, the diverter needed replacing as hot water went to the rads when called for.

The pump is brand new only put on yesterday, for what reason could it not be running on hot water delivery.

Sorry, i dont know the Indian your talking about...

Amy

 

[Agile]

The PCB did need replacing as only 110 volts were running through it, the diverter needed replacing as hot water went to the rads when called for.

The pump is brand new only put on yesterday, for what reason could it not be running on hot water delivery.

Sorry, i dont know the Indian your talking about...

Amy

I dont recognise any PCB fault which would cause "only 110 volts to run through it". Do you still have the old one and does it show any signs of distress on any component?

If the lower part of the diverter is seized up then this is usually as a result of oxides in the system. Probably why the pump has failed! The system water should be cleaned to prevent a reoccurance. The diverter can be cleaned and freed up after disassembling or in situ chemically.

The restaurant was the Nazma Brasserie, 15 Magdala Street. It was a nice meal and compares well with London restaurants.

Tony

 

[unclefewst]

hi chris, i am amy's dad, i am going to get some sentinel x400 and feed in through upstairs rad and run it in the system for 4 weeks or so, like it says on the tub, but i am not sure of what you mean in respect of filling it via the filling loop regards dave

Sludge or scale in the heat exchanger, or thermostat(s)/thermistor(s).

Kettling indicates boiler scale, so the easiest to try would be a Boiler Descaler, which you can just squirt in through the filling loop. Then run a bath or 3 to circulate it round the boiler (not diluting it into the rads)

Are you in a very hard water area?

 

[Amy Carter]

Agile, No sorry i dont have the old PCB.

The diverter has aslo been changed, but i agree with you the system does need de-scaling. This will be done asap. No doubt the diverter put pressure on the pump... whats done is done....

Amy

 

[Agile]

No, the dirt in the system which caused the diverter to seize up was probably wearing out the pump bearings or causing them to seize up as well.

Its quicker to use X800 ( Ferroquest ) than X400 as that only needs a couple of days.

Tony

 

[unclefewst]

we think we have this solved now, sentinell x400 now in the system and it appears to be getting better by the day, all the rads getting lovely and hot, and the water now starting to respond, will run it for the allotted time and then hard flush down thanks to all

 

[Agile]

X400 needs at least 3-4 weeks to have the best effect.