Boiler only runs for few minutes then stops.

[roosie]

Hi all.

My oil boiler is doing something weird, not sure if its the boiler or another component on the heating system.

My boiler will come on for around 3 to 4 mins and stop , it doesn't lock out and the mains light on the boiler is on .
It might come on about hour or 2 later but again for a few minutes.

This does this when I call for hot water or radiators .

I have checked the central heating pump which is only a few years old anyway thats seems like its working .

Can someone tell me I know the programming panel makes the boiler switch on regards to turning on mains light , what actually triggers boiler to startup?

 

[Terrywookfit]

Which boiler do you have?

 

[roosie]

Hi
Its a EcoFlam Minor 1

 

[roosie]

I have been thinking, the external waterpipe from boiler as it comes out and that is very hot, quick question the thermal shut off in the boiler when that "overheats" does it lock out the boiler or just stop it until it cools down enough to restart?

My water pump is a Danfoss Alpha2 when i up the speed i can hear water rushing so im pretty sure thats ok and as said its not very old.

 

[oldbuffer]

1. Programmer passes voltage to room thermostat (for heating) and cylinder thermostat (for hot water) only when in a "on" period.
2. If either thermostat senses the need for heat (room cooler than room thermostat setting, hot water cooler than cylinder thermostat setting) thermostat closes and sends voltage to motorised valve.
3. Motorised valve opens, and as it reaches the open position, closes a microswitch and send voltage to the boiler.
4. Boiler fires.

If you are sure the pump is OK, my first port of call would the motorised valve or valves. You may have a single three port valve (1 in, 1 out to heating, 1 out to hot water) or two 2 port valves.

 

[roosie]

1. Programmer passes voltage to room thermostat (for heating) and cylinder thermostat (for hot water) only when in a "on" period.
2. If either thermostat senses the need for heat (room cooler than room thermostat setting, hot water cooler than cylinder thermostat setting) thermostat closes and sends voltage to motorised valve.
3. Motorised valve opens, and as it reaches the open position, closes a microswitch and send voltage to the boiler.
4. Boiler fires.

If you are sure the pump is OK, my first port of call would the motorised valve or valves. You may have a single three port valve (1 in, 1 out to heating, 1 out to hot water) or two 2 port valves.

Thermostat works, its a old wall dial that clicks when it activates.

I have a 3 port Danfoss HS3 Valve, which is also only a few years old, anyway of testing this to see if it the valve, i did take head off it yesterday and turned the valve manually to see if that made any difference.

 

[Terrywookfit]

Hi
Its a EcoFlam Minor 1

That is the Burner. What boiler is it?

 

[roosie]

That is the Burner. What boiler is it?

Thermecon ( i can get model later) its fairly old 10-12 years +

 

[Terrywookfit]

Does any pipe work get warm?
Is the boiler hot to touch.
Sounds like a circulation problem.
A few pics of Boiler /Pump/ Valve would be helpfull

 

[roosie]

Does any pipe work get warm?
Is the boiler hot to touch.
Sounds like a circulation problem.
A few pics of Boiler /Pump/ Valve would be helpful

I know the output pipe of the boiler is hot i will get in the cupboard above the boiler to see how far the water stays warm upto the pump. i will get a picture of the setup later on.
Boiler is hot to touch as it does come on for a few mins every hour or so

 

[BoilerBob]

Get an electrician. Bob

 

[roosie]

Update:

Pump working as you can feel water rushing through pipes, and getting hot upto pump and beyond.

But

No radiators upstairs bleed , I can remove the whole bleed screws of them and nothing. Even with pump on and off.

 

[Harry Bloomfield]

No radiators upstairs bleed , I can remove the whole bleed screws of them and nothing. Even with pump on and off.

The boiler lacks any water circulation and is cutting out on its stat. Is it an open vented system, I would guess it is and the F&E tank is empty, not getting any water to fill it.

 

[ianmcd]

check for a blocked cold feed, you will need a good magnet to test

 

[terryplumb]

Blocked feed from the F&E ,causing water starvation is a possibility..