Oil fed worcester-bosch 12/15 Danesmoor boiler, which has stopped heating water

[GJUK]

Hi,

Thanks for your reply again, sorry for my slow response.

I had the boiler up and running for 4 days, on the timer all working fine. Then it has died again.

Same problem as first of all, no lights at all. Had to power it off and press both the clear button reset and the one under the top lip of the case. It ran for an hour then locked out again.

Are there any further basic troubleshooting steps I can take to get this thing running again please?

Thanks!

Jon

 

[GJUK]

Further update guys/query

When the boiler is 'on' should it be on constantly for the duration. ie, the timer is set between 7am and 8am, should the boiler be heating the water constantly for this time? As mine heats for 5 minutes, knocks off for 15 minutes, then on for 5 minutes.... then off for a further 15. The end result is warm water unless you have it set on the timer to 3 hours or so

 

[Burnerman]

What are your thermostats set at - both the boiler and the copper cylinder (if you have a stat on that?)
I'll stick my neck out and say that 1 hour of intermittent firing should be enough to get more than just warm water. Do the pipes that enter the cylinder feel very hot? They should do, and are there any bleed points in that vicinity?
The burner shouldn't be running constantly at this time.
Maybe there's some scale on the copper cylinder coil, lowering its efficiency......just another possibility.
John

 

[GJUK]

Hi,
dasadsadsdaws
On the cylinder it is set to 80*C.

The boiler is set to Max tempreture.

The copper tank was newly installed 4 years ago, it is the size of me, about 6 ft high and one of these solar ready type ones.

 

[oilhead]

You have a circulation problem. The boiler is not able to lose its heat, so cuts out on its own thermostat. Maybe the pump is not effective, or there is a possibility that the cylinder is not balanced and the water is passing through the coil too quickly. There is usually a gate valve to enable balancing.

 

[GJUK]

Hi,

I bit the bullet and had an engineer pop over.

I have to leave it on the 'c/heating' setting as the way it is wired, when only on 'hot water' setting the pump does not run. The boiler overheats and cuts off...

The c/heating is then controlled on the digital timer unit, on or off.

Learnt how it works now, £20 lighter but worth it so you are correct!!!

Thanks guys!!!

Jon

 

[simond]

So you've got a gravity HW circuit. The cylinder should be significantly higher (in altitude) than the boiler and also have a low resistance gravity indirect coil.

A modern cylinder, particularly a fast recovery one, will have too great a pipe resistance to allow proper gravity circulation, the old one would have had a relatively short wide bore coil inside.

You might be able to fix it by getting the solar and heating coils linked in parallel, thus halving the resistance and adding a bit of head. Bit unorthodox but might work.

Or get another motorised valve and make both HW and CH fully pumped, although this may compromise the cold feed and open vent arrangements.