Boiler stove boiling

Indoubt999

I have a boiler stove. Circulation pump is ok. Hot water Gravity lift is working Ok. Thermostat switching on pump after stove on for 10min. After a few hours burning water is boiling in the boiler. Very noisy. Sounds dangerous. Any ideas please.

monseiur

Hi,
Not a plumber, but....until the professionals come along - It seems that there's a problem with your circulating pump or stat. Do the rads. heat up and remain very hot to touch while the hot water cylinder is boiling/noisy ? If the hot water was circulating through out the house, as it should, the cylinder should not be boiling over, this assuming of course that you have an indirect cylinder system in other words that the domestic hot water and the central heating is interlinked.
Until such time as you get it checked out, when ever the hot water cylinder boils over, run the hot tap in the bath/ sink this will relieve the pressure in the cylinder.

OwenM

Indoubt999 wrote: »

Circulation pump is ok.

Circulation pump is not ok. It might be making some noise or vibration but it couldn't be effectively pumping if the water in the stove is boiling. Transient airlock maybe (just guessing, i'm not a plumber)

Are your rads very hot to touch?

It shouldn't be dangerous, i.e. risk of boiler exploding should not exist if it was installed properly but maybe damage could be done to the boiler itself, or maybe pipe and fittings failing due to extreme expansion/contraction and causing flooding.

jimf

get it checked out asap solid fuel is not something to take risks with

Indoubt999

Thanks for reply. Radiators are very hot. So is the hot water tank. Pump is 8 months old. When you turn it on the radiators are hot in minutes. Which is why I think it's working ok. Does this boiling water noise in the stove happen when it has reached its heating limit.radiators boiling and tank water boiling. Is it possible to fire it to hot.

Indoubt999

jimf wrote: »

get it checked out asap solid fuel is not something to take risks with

I would get it checked out but asked 3 plumbers and got 3 different answers. Surely someone has seen this. Maybe these plumbers don't have experience with stove faults

TPM

Indoubt999 wrote: »

"Radiators are very hot. So is the hot water tank". "When you turn it on the radiators are hot in minutes." "Is it possible to fire it to hot".

yes it is possible the fire is too hot.

You should be able to close down the stove to prevent it over heating the water, if you cant you have a problem with your stove and/or are over fueling it.

you NEED to get it checked out by someone who knows about solid fuel not just any plumber.

solid fuel boilers can be dangerous and if it is boiling it is without question in the dangerous bracket

Get it checked immediately

Wearb

Maybe a couple of fire bricks. Ask around for a good installer to see what they think of that idea. Maybe phone distributer.

Dtp1979

Post a few pics of the stove pipework and Hotpress as s whole

Indoubt999

Dtp1979 wrote: »

Post a few pics of the stove pipework and Hotpress as s whole

I had an open fire back boiler. The pipework hasn't changed. Only thing different is a boiler stove fitted. Never any boiling noise from the open fire back boiler. I'm at a loss

my3cents

Indoubt999 wrote: »

I had an open fire back boiler. The pipework hasn't changed. Only thing different is a boiler stove fitted. Never any boiling noise from the open fire back boiler. I'm at a loss

So there's your answer. The stove is massively more efficient at heating the water than the open fire was. Before 60% of your heat went up the chimney, now only 20% is doing that. Then the heat exchange is more efficient in a stove. If you have the stove on all day then a lot of the heat it produces is going into the water.

You need someone who knows a bit about stoves to take a look and check if your stove and boiler are the correct size for your system. Essentially it seems the boiler is too big or you are getting the stove too hot.

It might be just burning a bit less fuel with the air supply closed almost down would help.

I'd also suggest the installation wasn't done correctly as it should have taken the problems you have into account.

Did you just buy a stove then get someone to fit it?

monseiur

If you are burning coal, you could try mixing it with turf or low grade timber (not ash etc.)
How many rads. on the system, I would guess the output of your stove is twice the requirement for the no. & size of rads.
If your stove has a ''wrap around boiler'' you could fit a smaller back boiler, or else make the fire area smaller by fitting thicker fire bricks. Again it depends of the type of stove/ boiler etc. you have.
In the worst case scenario you may have to fit a smaller stove (or convert the attic and fit some big rads. in it !

Dtp1979

Indoubt999 wrote: »

I had an open fire back boiler. The pipework hasn't changed. Only thing different is a boiler stove fitted. Never any boiling noise from the open fire back boiler. I'm at a loss

Post a few pics of the pipework if you can

Indoubt999

Thanks for all the help. And great insight. I think I agree that I was sold a bigger then needed stove. I met an older retired plumber. And he said " sur jesus lad take it easy on the heat. You don't need a big roaring fire to do the job. Ya only have a small house not a castle " I suppose the older boys know there trade. I'll see what happens with a smaller fire going for the next few weeks. My fault for believing some fella in a hardware when he said "you would need every bit of that stove" thanks again

Dtp1979

Indoubt999 wrote: »

Thanks for all the help. And great insight. I think I agree that I was sold a bigger then needed stove. I met an older retired plumber. And he said " sur jesus lad take it easy on the heat. You don't need a big roaring fire to do the job. Ya only have a small house not a castle " I suppose the older boys know there trade. I'll see what happens with a smaller fire going for the next few weeks. My fault for believing some fella in a hardware when he said "you would need every bit of that stove" thanks again

Unless you've fitted a 30kw monster then 1" pipes should be enough to carry the heat if piped correctly. A solid fuel boiler should never boil the water the way you're describing

Indoubt999

A solid fuel boiler should never boil the water the way you're describing

Do you know this for certain. The pipes are 1inch. So a small fire is only going to hide the problem.

Dtp1979

Indoubt999 wrote: »

A solid fuel boiler should never boil the water the way you're describing

Do you know this for certain. The pipes are 1inch. So a small fire is only going to hide the problem.

It depends on the size of the boiler too

my3cents

Dtp1979 wrote: »

It depends on the size of the boiler too

And the size of the system its heating.

There can't be many rads if they were heated previously by a back boiler on an open fire.

Dtp1979

my3cents wrote: »

And the size of the system its heating.

There can't be many rads if they were heated previously by a back boiler on an open fire.

He said 8 rads I think.

TPM

there has been a lot good information posted up here from numerous people at least some of which are very knowledgeable on the subject (i am not familiar with all posters) and its all pointing to the same thing. you need to get the system checked out by a competent person.
the facts are
A correctly installed and used solid fuel system shouldn't boil the water.
A solid fuel system boiling water is dangerous.
Any system boiling water will have increased corrosion and premature failure
With out seeing the actual system any opinions given are based on assumptions

if you can post photos of the system you will get more relevant information and help (still not a substitute for an actually on site assessment but can still be very helpful.

one final point

The risks and dangers of solid fuel boiler systems are all too underestimated by users and plumbers, in extreme cases they can be fatal

Indoubt999

you need to get the system checked out by a competent person.

Thanks for the post. The problem is there are no competent persons at least in my area. I'm in Waterford. All I hear is guessing. Guessing from 2 "plumbers" that called to the house with 2 complete different fixes. I have no problem spending money on a fix but not on guessing. If the 2 lads said the same thing then the work would be done and this post would not be here. Also a solid fuel expert was motioned. Who is qualified in this field. I don't believe these experts exist. All I hear is guessing. You are right any boiling water enclosed or vented is dangerous hence the post. If you know some company close to me please let me know

Dtp1979

If you could post a few pics like u were asked then maybe someone here could help

longgonesilver

Have you tried running the stove with a smaller fire?

Any boiler that is any good would eventually boil the water in the system but they have thermostats that stop the fire when the water is hot enough. A solid fuel stove cannot cut out and relight on demand, all they can do is limit the amount of air getting to the fire and so the fire dies down slowly.

Indoubt999

I have ran the stove for the past 5 days with a smaller fire and you are correct. No boiling. I was hoping that this was seen by others and it is the norm for boiler stoves. I do think that it's a bit big for my house so maybe at full heat I don't have enough of a draw from it.


As regard the pictures. I have said this wasn't a problem when I had an open fire back boiler pipe work hasn't changed. So pipe work is ok. Unless you are saying that stoves are plumbed in differently

Dtp1979

Indoubt999 wrote: »

I have ran the stove for the past 5 days with a smaller fire and you are correct. No boiling. I was hoping that this was seen by others and it is the norm for boiler stoves. I do think that it's a bit big for my house so maybe at full heat I don't have enough of a draw from it.


As regard the pictures. I have said this wasn't a problem when I had an open fire back boiler pipe work hasn't changed. So pipe work is ok. Unless you are saying that stoves are plumbed in differently

Oh right sorry. I didn't realise you understood gravity pipework and it's associated safety features. I'm sure with your years of plumbing experience you've never seen a so called plumber do a stove changeover from back boiler and make a balls of the pipework. But it's ok. You know better

my3cents

Dtp1979 wrote: »

Oh right sorry. I didn't realise you understood gravity pipework and it's associated safety features. I'm sure with your years of plumbing experience you've never seen a so called plumber do a stove changeover from back boiler and make a balls of the pipework. But it's ok. You know better

Maybe you can explain what safety feature stops the water boiling if they were designed to be safe with a smaller source of heat?

Indoubt999

Dtp1979 wrote: »

Oh right sorry. I didn't realise you understood gravity pipework and it's associated safety features. I'm sure with your years of plumbing experience you've never seen a so called plumber do a stove changeover from back boiler and make a balls of the pipework. But it's ok. You know better

DTP1979 what's the problem

Water John

DTP, he is a new poster, a bit of latitude. Don't think he can post pics or links as he hasn't enough posts.

If a plumber put his in for you, get back to him and he should locate some one with specialist stove knowledge. Looks like its oversized. As some one else suggested, putting in fire bricks and limiting the water heating surface in the fire. It's a bit of a cobbled together solution but at least you wouldn't have to replace your purchase.

rpmcs

Unfortunately most builders providers/hardware sales men have no idea how to size a stove or even if they can they don't have/ take time to spec size of stove.
Or maybe they have lots of a certain stove in stock and want to sell them.

But if you look at your stove out put from its testing cert ( not from brochure/sales guy) and then

Get your plumber to measure rads and cylinder for hot water ... and compare out puts .

It's amazing how many times I have heard people saying plumer recommended this stove or another and not a clue how many radiators or even what size rads is in the customers house....

Dtp1979

my3cents wrote: »

Maybe you can explain what safety feature stops the water boiling if they were designed to be safe with a smaller source of heat?

Location of stat, cross plumbing pipes, fall on pipes. Not necessarily safety as such but if a prv was missing it'd also be spotted

TPM

OP i appreciate the difficulty of getting competent plumbers in relation to solid fuel, unfortunately this an issue country wide from what i here.

water boiling is due to
1)over firing of the boiler
2)the heat not been drawn from the boiler at a sufficent rate

Indoubt999 wrote: »

I have ran the stove for the past 5 days with a smaller fire and you are correct. No boiling. I was hoping that this was seen by others and it is the norm for boiler stoves. I do think that it's a bit big for my house so maybe at full heat I don't have enough of a draw from it.

the kw rating of the stove is the maximum it should quite happily run "closed down" to restrict the burning rate of the fuel in the stove and thus the heatoutput preventing the water from boiling.

if the stove continues to burn strongly when closed down there could be a problem with the stove drawing excess air (around doors, glass, dampers)
there could also be an issue with excessive draw on the chimney.

Indoubt999 wrote: »

As regard the pictures. I have said this wasn't a problem when I had an open fire back boiler pipe work hasn't changed. So pipe work is ok. Unless you are saying that stoves are plumbed in differently

Just because there wasnt a problem with the back boiler doesnt mean it was actually plumbed correctly, back boilers are not efficient they loose alot of heat up the chimney, where as a stove can transfer a lot more heat to the water for the same amount of fuel burnt. (I once seen a back boiler tha ran for years with out any "problems" the primary circuit was piped a couple of meters in 3/4" pipe :eek: )


There could also have been a slight change to the plumbing that could cause issues a eg. pipe moved resulting in a negative rise, an injector tee replaced with a normal one.

Posters here are trying to relate their knowledge to individual problems from just reading text and this is certainly a case where a picture can speak 1000 words. the more information given the more relevant the replies can be.

here are some of the questions we would have in mind when looking at a solid fuel boiler

what make/model and output is the stove?
is there a second heat source on the system?
what size is your cylinder? is it insulated?
does the system have a heat leak radiator?
you say the circulating pump is ok why do you say that? (new pumps can fail)
what fuel do you burn?
when the stove is burning and not boiling is the hot water circulating into the attic tank?
are there any valves on the pipework from the stove to the cylinder?
how does the rad circuit tee into the primary circuit?
and the what is the plumbing layout like?, (this is where photos can help)

browner85

Just a taught.... But could it be the stat wired backwards where it is switching the pump off when it hits a certain temperature ?