Danesmoor 20/25 control box problem

[Brainy]

Hi

I have recently had a problem with my 26 year old worcester Danesmoor boiler where the transformer went wrong and burnt out the control box.

I have tried to get a like for like but cannot seem to find it.

Instead I am offered a base plate adapter and a different type of controler and it does not seem to work.
The adapter I Have been given is BHA 11/12 and BHO72.10 controller

The boiler will fire up but locks out after 5 or so seconds indicating that it is not seeing a flame.

It has oil, pump pressure, a new solenoid, a new photo cell and trans former. I also replaced the ht leads whilst replacing the transformer.

Is there anyone that can help me on this one please as I am pulling my hair out at the moment.

The controller I took off was a Danfoss BHO70 1.0.
The wiring on the buner only has 9 terminals and number 1 is blank. The new controller has 12.

The original manual states a Danfoss BHO 11 or 57 H3 if they mean anything to those experienced in older worcesters.

It would be great to get it up and running before it gets cold.

Cheers

Rich

 

[Tipper]

Whilst the base plate thingy looks simple you actually have to rewire it to make it work.

Check out the wiring diagrams that come with the base plate and new control box and set it up like that. You may have to change the type of photocell to match the new box as well if you have not already done so.

 

[casius66]

Look at the wiring for the photocell, I think it's terminals 7 & 9 that have to be rewired (take the whole screw out and move the silver terminal over then screw in again) - don't hold me to the numbers (I change over to satronic to save carrying various boxes so I can't nip out and check this), look at where the PC was wired on the old box then look at wiring for new one.

 

[Boilerman2]

I wouldn't bother with those sdo called adapter bases, they are a waste of time as you have to alter the wiring on the original base to suit terminals 7&9 play a part, but without being in front of it I can't quite remember.

I would sugest you buy a Satronic TF830.3 Control Box, + a Base & Wiring plate, dissconnect every thing from the old base, take it off , fit the new satronic base, and rewire everything to it, the back of the 830 shows where all the wires go, I don't think it is any harder than messing around with those horrible adaptors

 

[Brainy]

Thanks for the swift replys and good advice.

I looked at Danfoss instructions as to using the base and controller and it points out that the oil pre heater terminals need to be shorted if the boiler does not have a preheater. That is terminal 3 and 8 on the base converter and would be the soleniod and switch live on my boiler.

Now if this is the case and it was not done, could it cause the boiler to lock out after 5 or so secs of igniting or would it not make any difference?

I need to try and get my head around this mess. I now know why I fit bathrooms and not boilers

Rich

 

[Brainy]

Well after a few more hours tinkering I have decided to replace the whole burner.

It will be easier for me than fiddling with the wiring.

Thanks again for the advice.

Rich

 

[Brainy]

I have now replaced the burner with a EOGB X400 and it runs superb.

It now proves to me that there was a issue with the control box that I was sold.

I am setting the old burner up in a test rig to try and get a control box to work on it.

Thanks everyone who replied.

 

[Burnerman]

You'll find a circuit and timing diagram on the inside of the control box...I test these (wearing ones anorak) using some 240v light bulbs, cable and sockets - one to represent the fan, one for the electrodes spark, and one power to the burner oil valve.
How sad is that?
John

 

[Brainy]

Thanks that is useful to know.

I will get to the bottom of the fault if it kills me

Rich

 

[Burnerman]

Don't forget - when you run the burner up on the bench - to tease the photocell into thinking that its dark until it lights up
John