Home heating boiler won't switch on from timer.

[binksy3]

Hi,
I am new to this so bear with me.
I have a firebird home heating boiler that won't start from the program/timer.
I thought at first I had run out of oil but that isn't the case and when I go to the boiler and hit the red button it comes on no bother...
So I switched it off again and this time hit the boost button on the program and listened to see if the boiler tried to fire up but nothing happened, again I hit the red button and it went and stayed on for the duration of the boost.
Is it a problem with the program/timer or something else?
Any help is much appreciated.
Oh and the program/timer is a Hodrstman H37XL.

 

[Jackrae]

If the boost button part of the timer/clock mechanism and pressing the magic red button made the boiler fire for the duration of the boost then it suggests a logic fault. More information need to permit sensible response

 

[binksy3]

Thanks Jackrae.
It is a Horstmann H37XL timer, the boost button itself is located on the clock/timer.
The only thing that seems to make it fire is when I hit the red button on the actual burner, neither boost nor timer get it going.

 

[MANDATE]

My thoughts are that the programmer/timer is most likely OK.
The boiler lights when you press the 'reset' on the 'control box' so power is available at the control box.
What I think you've not realized is the boiler must have gone to 'lockout mode' and has to be reset after fixing whatever problem caused it to go to lockout.

 

[binksy3]

Thanks MANDATE.
How do I reset it?
I seen on anther blog that you need to switch the power off at the boiler for 30 secounds???

 

[MANDATE]

You reset it by pushing the button down which you have done.
When it goes to lockout you have to wait about two minutes before resetting.
This I think is to allow a small heating element to cool down,otherwise it wont reset.
You can reset it with the controls off and then use the controls to fire boiler or if the controls are already on, then resetting will start the operation.
There are a few things that can go wrong while boiler is running which would cause lockout.
For example a faulty solenoid coil sometimes works ok when its cool so boiler starts ok, but heat causes the coil to fail, it cuts off the oil so no light to photo cell, boiler goes to lockout.
After coil has cooled, it may well work again (that is after resetting the control box)

 

[binksy3]

Thanks again.
I think it is the coil as you described.
I was working at it again last night and it just won't start from the timer. I can go out and hit the red button to get it going but after roughly ten mintues it stops and won't fire again unless I hit the red button again.

 

[MANDATE]

As I said it's going to lockout and therefore in can't start from timer until control box has been re set.
If timer is already on, pressing re set will also switch boiler on.
If timer is off, pressing reset will re set the control box but boiler will not start till you switch timer on.
To solve the problem you have to find what is causing it to go to lockout and it does sound like a faulty 'solenoid' where the coil goes open circuit due to heat. eventually it will go to lockout and you won't be able to restart.

 

[binksy3]

Is there any way to know for sure or to test the solenoid coil?

 

[MANDATE]

If the coil is faulty, then continuity of the electrical path has been lost lost and so has the magnetic field.
You can simulate its operation or test for continuity in the workshop.
There is test equipment available to detect if magnetic field is present or not but not cheap. I assume its a bulb holder with bulb and battery and uses a 'reed' switch which closes when placed near a magnetic field.

 

[Agile]

You seem to be saying that it runs as long as you call for heat.

I wonder if its overheating when the demand ceases?

Perhaps no working pump over run?

Tony

 

[MANDATE]

My opinion is, any over heating would operate the boiler stat and boiler would go into standby mode until boiled cooled, when it would restart automatically.
To me boiler is going into lockout mode and it can't be restarted until control box is reset.
Control box could be reset with programmer/timer 'off' or 'on'.
In the case of programmer on, re setting will also switch boiler on, which it can't with programmer/timer off.
The fact it starts and runs for short periods is typical of solenoid failure. So it needs to be ruled out one way or another. tested or exchanged. wouldn't you agree?

 

[MANDATE]

Just checking to see if you have resolved your problem? If so What was the cause?