Noisy boiler

[BOROBOY2]

Hi all,
I own a 20 year + Vulcan conventional boiler. Had the burners & jets cleaned recently. Since I've had them cleaned, the boiler seems nosier than normal. When it's first turned on in the morning, sounds like a steam train. After around half an hour, then becomes quieter. This also occurs when I've drained the hot water from the tank.

Could the gas pressure now be slightly higher, causing the boiler to be nosier when cold? Any idea's?

Thanks.

George.

 

[Slugbabydotcom]

Could be as you say. Could be getting sludgy or perhaps a pump on its last legs. Can you turn the pump speed up a notch and/or perhaps the boiler stat down a little?

Mines a pork parmo from Mike's return if this info is of any use

 

[BOROBOY2]

Slugbaby,
Thanks for your reply. I'd changed the pump 2 years ago. Have tried turning it up & the noise increases. I may try turning the stat down a little & see what happens. It's on 4 at the moment, I'll try turning it down to 3, at it goes up to 6.

I want to keep the boiler if I can, don't think a modern boiler would out last this one. Think it's probably been in the house since the late 70's.

Would it be worth putting a noise reducer inhibitor into my system? Do they work?

Pork parmo my favourite If you ever visit, I'll buy you one

George.

 

[Slugbabydotcom]

Have tried turning it up & the noise increases.

That doesn't really compute! If its a kettling noise then increasing the speed pf water through the boiler should even the temperature out and reduce the kettling. The only way slowing the flow down would stop any noise is if the noise where caused by a hard restriction which is not the noise you are describing.

Maybe you have the numbers wrong? on a 3 speed pump 3 is high and 1 is low.

Have you removed or turned off the nearest rad to the boiler? It could have been acting like a bypass which would have reduced the noise.

Old boilers always tend to be noisy anyway. I have a similar relic and the usable range on my stat is between 3 and 3½

Noise reducer can help but its best to at least do a basic flush with the system to see if sludge is the problem, then top up with inhibitor and add the noise reducer if theres still a problem

I am that pork parmo munching smoggie! Theres not that many places now that do a pork parmo.and thats part of the reason I dont use the union flag.

 

[BOROBOY2]

I changed the pump myself, it's 3 speed & it's on 1 at the moment. When I tried turning the speed up the noise speeded up. This noise only occurs whilst the boiler is cold.

All the rads in the house work fine & I drained the system last year & put thermo valves on all the rads apart from 1. The rad above the boiler on second floor, heats up very slowly. Someone said to me that that's caused by convection?

I have now turned the stat down to 3, from 4 & I'll see how it goes.

Think the boiler has prob been in my house for 25 years now. When I do eventually come to change it, would it be worth changing the plumbing as well? How long do copper soldered joints last? I'd rather go for reliability, than slightly improved efficiency when it comes to a new boiler. I have replaced most of the rads in the house now.

Your right about the good old pork parmo, most take always now sell chicken ones. I now live outside boro, but it's only a 20 min drive. Still support MFC though, for better for worse.

Thanks for the advice.

 

[Slugbabydotcom]

When I tried turning the speed up the noise speeded up. This noise only occurs whilst the boiler is cold.

This tends to point to a flow restriction type noise. I have some ideas on this:-
1 Open the TRV to full on the nearest rad to the boiler but disregard the rad you mention below
2 Wilo pumps use the water as a lubricant and are not very tolerant of sludge. Is the pump the source of the noise? A better description of the noise would help

All the rads in the house work fine & I drained the system last year & put thermo valves on all the rads apart from 1. The rad above the boiler on second floor, heats up very slowly. Someone said to me that that's caused by convection?

I have a feeling they mean what we call gravity flow. A relic from the days of solid fuel where a radiator or towel rail was fitted to the pipes that heated up the hot water to dissipate excess heat

I have now turned the stat down to 3, from 4 & I'll see how it goes.

Think the boiler has prob been in my house for 25 years now. When I do eventually come to change it, would it be worth changing the plumbing as well? How long do copper soldered joints last?

Going by the last time I replaced a boiler after removing a Vulcan I would recommend renewing all the pipework. I did powerflush thoroughly but ended up replacing some badly crudded pipes that the powerflusher and several doses of chemicals hardly touched.

I'd rather go for reliability, than slightly improved efficiency when it comes to a new boiler. I have replaced most of the rads in the house now.

Modern boilers arent as reliable as the old ones. There are so many demands on manufacturers now that they had to fill their boilers with more things to go wrong. Run the old thing into the ground and remember these as the last of the good old days. Most energy efficient isn't always the cheapest and when you do proper sums it still takes too long to get a return on an investment in a modern boiler in most cases

Had the burners & jets cleaned recently.
Could the gas pressure now be slightly higher, causing the boiler to be nosier when cold?

We still haven't totally ruled this area [loosely speaking] out. This is when your problems started after all. Did whoever cleaned the jets out check the burner pressure and gas rate afterwards?

 

[BOROBOY2]

You wrote:-
1 Open the TRV to full on the nearest rad to the boiler but disregard the rad you mention below
2 Wilo pumps use the water as a lubricant and are not very tolerant of sludge. Is the pump the source of the noise? A better description of the noise would help.


Sorry, what do you mean by TRV? Do you also mean the rad that heats up first?

I replaced the original pump with a Wilo Gold 60.

Don't think it's the pump making the noise, sounds like the boiler. After further inspection noise doesn't get any worse whether I turn the stat up or down & the same whether I turn the pump speed up or down.

Noise sounds like a steam train gathering up speed. After around half an hour the boiler makes normal kettling noises. If that makes sense?

You also wrote:- Did whoever cleaned the jets out check the burner pressure and gas rate.

Answer, no. Whomever cleaned burners, did so by taking the front inspection panel out & brushing inside.

The boiler is a Sideal Vulcan.

Thanks.

 

[Slugbabydotcom]

Forget about the rad above the boiler with no TRV [thermostatic radiator valve] Go to the nearest rad to the boiler and open the valve fully.
This will have the effect of creating a bypass short circuiting some hot water back to the boiler. If a temp rise is too great as water passes through the boiler you can get noises such as this.

You also wrote:- Did whoever cleaned the jets out check the burner pressure and gas rate.

Answer, no. Whomever cleaned burners, did so by taking the front inspection panel out & brushing inside.

If the boiler was serviced then the heat transfer from flame to water will be more efficient. This may well be the reason you get noise and apart from checking the boiler pressure and gas rate making any adjustments theres little that can be done. Otherwise so long as they werent prodding the jets with a pin; cleaning as you have described should have no detrimental effect.

I am starting to struggle now as I can't see or hear the system. Hopefully something we have touched on will lead you in the right direction.

 

[BOROBOY2]

Thanks again for your input.

I've tried opening up the TRV, made no difference.

Would in be worth draining the system & adding inhibitors? I did that around 2 years ago & used fernox boiler noise reducer for the general kettling sounds. Seemd to help for around 3 months, then back to normal again.

The burners were lightly brushed just to clean away the soot deposits.

Would a corgi guy be able to adjust the gas pressure? As I have no instructions.

George.

 

[Slugbabydotcom]

Would it be worth draining the system & adding inhibitors? I did that around 2 years ago & used fernox boiler noise reducer for the general kettling sounds. Seemd to help for around 3 months, then back to normal again.

Maybe a powerflush would be better. Certainly a basic flush and treatment will help somewhat and not do any harm. There is usually a drain off on or near the boiler which will help get some crud out of its heat exchanger. Use this one especially if you didnt last time. Expect to renew the valve as it may be past its best by now.

The burners were lightly brushed just to clean away the soot deposits.

Do you mean the burners were cleaned in addition to the jets?

Would a corgi guy be able to adjust the gas pressure? As I have no instructions.

He would so long as there was a dataplate attached or he could get the necessary information from somewhere. Reading between the lines I feel the attention of a corgi guy is well overdue. Theres a lot of things that could be wrong but a decent corgi would suss out straight away if he was looking at it. Take a look at my post #11 in the FAQ's to get a better understanding of the issues that need to be considered. It was written with 1980's boilers in mind so it's better if you get the jist of it rather than following to the letter. eg your boiler won't have pump over run or a by-pass.

 

[BOROBOY2]

Would it be worth draining the system & adding inhibitors? I did that around 2 years ago & used fernox boiler noise reducer for the general kettling sounds. Seemd to help for around 3 months, then back to normal again.

Maybe a powerflush would be better. Certainly a basic flush and treatment will help somewhat and not do any harm. There is usually a drain off on or near the boiler which will help get some crud out of its heat exchanger. Use this one especially if you didnt last time. Expect to renew the valve as it may be past its best by now.

The burners were lightly brushed just to clean away the soot deposits.

Do you mean the burners were cleaned in addition to the jets?

Would a corgi guy be able to adjust the gas pressure? As I have no instructions.

He would so long as there was a dataplate attached or he could get the necessary information from somewhere. Reading between the lines I feel the attention of a corgi guy is well overdue. Theres a lot of things that could be wrong but a decent corgi would suss out straight away if he was looking at it. Take a look at my post #11 in the FAQ's to get a better understanding of the issues that need to be considered. It was written with 1980's boilers in mind so it's better if you get the jist of it rather than following to the letter. eg your boiler won't have pump over run or a by-pass.

Thanks for info, interesting reading for an amateur like myself.

A plumber guy from around the corner, brushed the burners down & that's all he did.

Think as you say might be worth getting an expert in to give an opinion on the boiler. I would like to keep it if possible though.

Another thought. I replaced the original pump that was on the boiler like for like. The hot water leaves the boiler & then the pump pushes the water back around the system towards the boiler. This has always been the case, as I made sure the directional flow indicator matched that of the original pump, when I changed it. Is that the normal set up? Thought pumps normally push water directly into the boiler?

 

[namsag]

Vulcan continental now over 30 year old last ones fitted around 1975. Hang on you say burners brushed to remove soot deposits if there was soot there the heat exchanger will need cleaning properly on a continental this would take around half hour and he would be filthy at the end of it,, sounds like you need proper service done.. Sooty boilers are noisy as burner can back light

 

[Slugbabydotcom]

A plumber guy from around the corner, brushed the burners down & that's all he did.

Think as you say might be worth getting an expert in to give an opinion on the boiler.

When a customer watches a guy working on the boiler he sees different things to what the guy does. I can't say whether or not he has done a proper job but if he isn't corgi then legally he shouldn't have touched it.

If I take what you say literally then I do get concerned about the safety issues.

Definitely worth getting a corgi round who you can trust to give an honest opinion and check things over. Thats the difficult part as there are so many boiler salesmen about.