Noise from boiler

Rob32

Hi guys,

This is a never ending list of issue with a gas boiler in a rented house. Initially I was pushing to have it serviced as I didnt know when it was last done, got that sorted and my gf informed the plumber i was bleeding the rads every couple of weeks, he suggested a leak came back and drained the system put some sealer in etc now when the boilers coming on maybe 20secs after firing it starts this horrible banging/clanking sound as if somethings exploding in it, its also not heating the radiators as good as it was and not heating the hot water tank. Im assuming this is happening as it appears to be thinking the waters getting to temp in less than a minute and knocking off. Thermostat is set to 25degrees as it always has been but the radiators/house definitly arent getting as warm. Any ideas?

corkgsxr

Can ya feel the pump spinning.

Some leak sealers can stop the pump.

Rob32

corkgsxr wrote: »

Can ya feel the pump spinning.

Some leak sealers can stop the pump.

Havent checked that, I can hear it pumping or at least trying to pump, if its managing to pump or not i dont know. Would that explain the random banging though?

corkgsxr

Rob32 wrote: »

Havent checked that, I can hear it pumping or at least trying to pump, if its managing to pump or not i dont know. Would that explain the random banging though?

Banging is probably the boiler overheating, could be a few things, pump bit shagged, airlocked after draining.

Much noise like air flying around?

Rob32

corkgsxr wrote: »

Banging is probably the boiler overheating, could be a few things, pump bit shagged, airlocked after draining.

Much noise like air flying around?

It could be air, i bled the radiators last night and that quietened it down a small bit. Ive also noticed when the banging is happening the pressure needle on the boiler jumps around, it also usually sits around 2bar which the plumber has said before is too much.

jimjimt

Seems more like a partially blocked heat exchanger.

shane0007

jimjimt wrote: »

Seems more like a partially blocked heat exchanger.

I would agree. It is more like blocked heat exchanger. What's the make & model of the boiler?

Rob32

shane0007 wrote: »

I would agree. It is more like blocked heat exchanger. What's the make & model of the boiler?

Honestly havent a clue, the plumber did mention its the cheapest boiler you could buy at the time that the house was built! maybe 6-7 years ago in case you guys are wondering. what would a blocked heat exchanger mean for it? is it dangerous or easily fixable?

joydivision

Pipes getting red hot .Thermostat knocking off before rads heat . The system was recently drained ? Id go with an airlock .

JohnnieK

Some heat exchangers can be removed and flushed and this normally sorts it out. If it keeps going like that it could split and start leaking. Either way it's not right and your landlord needs to get this sorted now.

Rob32

joydivision wrote: »

Pipes getting red hot .Thermostat knocking off before rads heat . The system was recently drained ? Id go with an airlock .

I havent checked the pipes from the boiler so not sure if there getting red hot.

How do I fix an airlock? if I could try that myself then I could rule out an airlock or even get it sorted my self tonight!!

shane0007

Rob32 wrote: »

I havent checked the pipes from the boiler so not sure if there getting red hot.

How do I fix an airlock? if I could try that myself then I could rule out an airlock or even get it sorted my self tonight!!

I would doubt very much it is an airlock within the boiler and if the air lock was external, the boiler would not be banging.
You need an RGI.
The make and model of the boiler will be on the RGII certificate issued to you when it was serviced.

Rob32

shane0007 wrote: »

I would doubt very much it is an airlock within the boiler and if the air lock was external, the boiler would not be banging.
You need an RGI.
The make and model of the boiler will be on the RGII certificate issued to you when it was serviced.

It was given to the landlord as far as I know, I was going to get it but I was in work when he called, the other halfs sister met him there.

If the heat exchanger is the issue is the boiler ok to use? Bearing in mind we need it on longer than normal to get any heat into the house.

jimjimt

Regardless of air lock or blocked heat exchanger. Gas boiler are delicate petals to abuse like that. Best leave it alone. Phone the plumber if he is not RGII registered ask him to recommend someone. If you keep forcing it to run and overheat you will do serious harm.

corkgsxr

Rob32 wrote: »

I havent checked the pipes from the boiler so not sure if there getting red hot.

How do I fix an airlock? if I could try that myself then I could rule out an airlock or even get it sorted my self tonight!!

Any rads get very hot?

Close them down and see if the heat goes to other rads, keep closing down rads as the the heat gets to them, when all heat open them back up. You also need to open and close down the cylinder. If its a drop system or piped badly you might have to crack fittings a small bit to leave out air, only do that if your confidant to do

Rob32

jimjimt wrote: »

Regardless of air lock or blocked heat exchanger. Gas boiler are delicate petals to abuse like that. Best leave it alone. Phone the plumber if he is not RGII registered ask him to recommend someone. If you keep forcing it to run and overheat you will do serious harm.

He is RGII however the landlady insists she deals with him ive informed her and told her I want it checked asap, so basically dont use the boiler?

shane0007

No point. It will just do damage if the heat exchanger is blocked. Let us know how you get on.

Rob32

corkgsxr wrote: »

Any rads get very hot?

Close them down and see if the heat goes to other rads, keep closing down rads as the the heat gets to them, when all heat open them back up. You also need to open and close down the cylinder. If its a drop system or piped badly you might have to crack fittings a small bit to leave out air, only do that if your confidant to do

Not that ive noticed some do get hotter than others though! The refill valve is generally closed but id have no issues bleeding/refilling the system anyway,

corkgsxr

Rob32 wrote: »

It was given to the landlord as far as I know, I was going to get it but I was in work when he called, the other halfs sister met him there.

If the heat exchanger is the issue is the boiler ok to use? Bearing in mind we need it on longer than normal to get any heat into the house.

Not really no, fairly thin metal in the alu ones. Won't like abuse, and it'll be costing you in gas so get them to sort it

Rob32

shane0007 wrote: »

No point. It will just do damage if the heat exchanger is blocked. Let us know how you get on.

Well im going to set up a electric heater in the childs room and ring her tomorrow saying i spoke to a plumber friend and he said not to use it, it could be dangerous

thanks all for the help ill update soon as

shane0007

Rob32 wrote: »

Ive also noticed when the banging is happening the pressure needle on the boiler jumps around

This is a symptom of a blocked heat exchanger.

JohnnieK

Rob32 wrote: »

It was given to the landlord as far as I know, I was going to get it but I was in work when he called, the other halfs sister met him there.

If the heat exchanger is the issue is the boiler ok to use? Bearing in mind we need it on longer than normal to get any heat into the house.

It should be left in the premises where the appliance is and you pay the gas bill at the end of the day.

Rob32

JohnnieK wrote: »

It should be left in the premises where the appliance is and you pay the gas bill at the end of the day.

Really? I didnt know that, I dont mind the bill once the childs warm enough basically I wanna know if its likely something could fail an injure anyone!

JohnnieK

If you kept using it the heat exchanger could start leaking and in theory it could short the pcb of the boiler. If you have stopped using it then you have nothing to worry about except for the cold.

Rob32

JohnnieK wrote: »

If you kept using it the heat exchanger could start leaking and in theory it could short the pcb of the boiler. If you have stopped using it then you have nothing to worry about except for the cold.

I cant really justify not using it unless it poses a danger, as said ive a child (1 yr old) to keep warm, ive just checked and the heater outlet pipe is boiling and the return is freezing, I bled the rads again (no air) an turned off the rads that arent. essential and the banging has stopped! Calm before the storm??

corkgsxr

Rob32 wrote: »

I cant really justify not using it unless it poses a danger, as said ive a child (1 yr old) to keep warm, ive just checked and the heater outlet pipe is boiling and the return is freezing, I bled the rads again (no air) an turned off the rads that arent. essential and the banging has stopped! Calm before the storm??

Shouldn't be used. It's like if your car was running on 2 cylinders, it'll get ya round but ya shouldn't

Rob32

Ok off it goes so, anyone any hints for keeping warm haha

corkgsxr

Rob32 wrote: »

Ok off it goes so, anyone any hints for keeping warm haha

Buy the wife some flowers

Rob32

corkgsxr wrote: »

Buy the wife some flowers

Im concerned about keeping the baby warm not me haha!

DGOBS

easy enough keep the child warm, it's cooling them down is the difficult bit!

Rob32

***UPDATE***


So the plumber arrived wednesday finally (Im currently looking into lodging a formal complaint with the PRTB about this, 3days in a house with no heating with a baby is unacceptable IMO) anyway... after flushing the boiler twice lubricating the pump and changing the heat exchanger the boiler is now functioning correctly and quietly. It also seems the high pressure the boiler seemed determined to operate (part of the origional complaint about the boiler two months ago) was because of the heat exchanger being partially blocked as its now functioning happily at the correct pressure. Thanks everyone for your advice guys!

joydivision

jimjimt wrote: »

Seems more like a partially blocked heat exchanger.

Good diagnosis. No flies on this fella.

jimjimt

Nice to hear you have got heating.
Be aware heat exchangers do not just clog up without reason. Perhaps a leak in the system. If the reason why is not found it will clog again. Sooner than you think.

Was the question asked, why did it block ?

The system in full needs to be flushed and pressured tested for a leak. Add a magna filter to help keep it all clean.

Good diagnosis. No flies on this fella.

Thanks joydivision. Been plumbing from the late 80's in my parker and doc martins and still learning everyday.