Potterton Kingfisher cf 100 ch luke warm

[DerekJB]

Hi I have an issue with a Kingfisher cf 100, when set on HW it heats up fine but when it calls for CH it only runs luke warm, it has 2 pumps one near the tank and one further down to help push it round 10 rads, it has one 2 port valve to divert between ch/hw. when on h/w boiler runs fine and water in supply line is very hot. [happy days] as soon as request for CH happens port valve changes [good] but the temp of the pipe comming straight out of the back of the boiler is only warm ish [can hold pipe 2 feet from boiler with no risk of burning fingers etc] [wouldn't even make a cup of tea] boiler runs but goes off and on quite quickly, there is a thermostat in hallway and this does turn the boiler on and off. but it just sits there ticking over the HW is run via the boiler stat =non fitted on tank and no emersion heat connected either, any help would be greatly recieved,
Thanks

 

[Hardy1]

just had a look on your boiler manufacturer instructions to see what boiler that is- check pump, and also check central heating thermistors(have known to pack up on these boilers)

 

[Puddle]

Did it work ok last year ?

 

[BLOD]

if I've understood your post I'd say the boilers working ok and you need to look at the system controls. Pump, valve stat etc

 

[DerekJB]

Hi Thanks for the info, guy had the boiler serviced every year, and I agree boiler seems to be fine but the owner cleaned out the f/e in summer thought maybe crap in system somewhere just never come across one of these and wondered if the were prone to any faults [only quallified this year] change of career for 57 year old lol. I have looked at this forum in the past and find it the most helpful.
Cheers

 

[DerekJB]

Hi again excuse ignorance but having checked the manual for the boiler there is only on thermostat shown that is the expansion phial type there are none on the pipe work as in a combi [none that I can see anyway. by thermistor do you mean the room thermosat thermistor sensor?

 

[mfgs]

There are no thermistors on the boiler.

 

[Billy Bob Bob]

i would say your 3 ports shot they are designed to fail to DHW it may be making the right noises,but not moving the valve pendulum try taking the head off if you can and manually altering the valve spindle to ch

 

[peemac]

Re: Potterton Kingfisher 2 - no CH no HW

I have the Kingfisher 2 as well and it stopped working last night. Well when i say it stopped what i mean is the pilot light is still on, the thermostat in the hall still kicks it on and off, but the pump makes a loud spinning noise once it kicks in (like there isnt any water going to it). The water doesnt get hot nor does the CH warm-up.

We changed one of the rads + values the other week and spent the whole day bleeding the system. It eventually worked, but now no such luck.

Do i have to bleed the rads and the boiler now or is there another way?

 

[DerekJB]

Hi gas man there is only a 2 port valve in line, when I turn selector on control for hw all is fine as soon a ch is called for every thing goes luke warm.
thanks for heads up anyway

 

[mfgs]

Is the 2 port on the heating or hot water? Fully pumped or gravity?