Steam in the attic

Wearb

I had a call from a customer who said that there is sometimes steam in his attic. His only heat source (except for a few backup electric heaters) is his oil boiler. I have an idea what the problem is, but I don't want to pre-empt potential answers by revealing my guess.

Any ideas of the cause?

sullzz

Wearb wrote: »

I had a call from a customer who said that there is sometimes steam in his attic. His only heat source (except for a few backup electric heaters) is his oil boiler. I have an idea what the problem is, but I don't want to pre-empt potential answers by revealing my guess.

Any ideas of the cause?

Vent pipe pitching ?

Turbohymac

Well. Wearb..it sounds like you're a plumber as one of your customers has steam at times in his attic...
Big question are you just giving us all a guess or are you only a 5/8 plumber hoping someone here can point you in the right direction..

Either oil heating system getting too hot due to an issue with a circulation pump or its wrap on the pipe thermo sensor getting faulty otherwise could even be steam from his shower if fan is venting to attic..
Now hopefully you're one of the nicer mods and don't give infractions..

ArthurG

Turbohymac wrote: »

Well. Wearb..it sounds like you're a plumber as one of your customers has steam at times in his attic...
Big question are you just giving us all a guess or are you only a 5/8 plumber hoping someone here can point you in the right direction..

Either oil heating system getting too hot due to an issue with a circulation pump or its wrap on the pipe thermo sensor getting faulty otherwise could even be steam from his shower if fan is venting to attic..
Now hopefully you're one of the nicer mods and don't give infractions..

Given he’s a mod for the plumbing forum I’d suspect he’s legit 🙄

Wearb

Turbohymac wrote: »

Well. Wearb..it sounds like you're a plumber as one of your customers has steam at times in his attic...
Big question are you just giving us all a guess or are you only a 5/8 plumber hoping someone here can point you in the right direction..

Either oil heating system getting too hot due to an issue with a circulation pump or its wrap on the pipe thermo sensor getting faulty otherwise could even be steam from his shower if fan is venting to attic..
Now hopefully you're one of the nicer mods and don't give infractions..

I am not one of the nicer mods and if you had answered anyone else like that I would have cautioned you, but seeing that your second paragraph made sense, no caution this time.

swarlb

I'm not a plumber although I am an engineer of sorts...
Recently I had a new pump fitted, along with a new boiler to an existing Stanley (solid fuel) range. The system is dual, oil by external boiler and pump, and solid fuel range also with pump.
Since the fitment I heard a 'gurgling' sound from the attic. The overflow pipe into the small tank trickles hot water when the range is on. This does not happen when the oil system is used. The range has a more powerful pump than the oil system, so this may be the cause.
Any ideas ?

Turbohymac

Oh Goodie do I win any prize...
Happy xmas all..

sullzz

Turbohymac wrote: »

Oh Goodie do I win any prize...
Happy xmas all..

I think you just lost all credibility when you said " oh goodie".

John.G

swarlb wrote: »

I'm not a plumber although I am an engineer of sorts...
Recently I had a new pump fitted, along with a new boiler to an existing Stanley (solid fuel) range. The system is dual, oil by external boiler and pump, and solid fuel range also with pump.
Since the fitment I heard a 'gurgling' sound from the attic. The overflow pipe into the small tank trickles hot water when the range is on. This does not happen when the oil system is used. The range has a more powerful pump than the oil system, so this may be the cause.
Any ideas ?

Any idea what the old pump was and what was speed setting, also what is the new pump make/model, A Rated? and the current setting, I'm fairly sure then it can be matched to the old one or if old model not known then setting can still be changed.

swarlb

John.G wrote: »

Any idea what the old pump was and what was speed setting, also what is the new pump make/model, A Rated? and the current setting, I'm fairly sure then it can be matched to the old one or if old model not known then setting can still be changed.

No idea of make, the old one was a standard looking 'red' in colour. The new one has a push button digital setting with several different settings.
The reason I asked for a more powerful pump is because the rads furthest away from the pump never really warmed up, even when balanced.

John.G

swarlb wrote: »

No idea of make, the old one was a standard looking 'red' in colour. The new one has a push button digital setting with several different settings.
The reason I asked for a more powerful pump is because the rads furthest away from the pump never really warmed up, even when balanced.

It would be a big help if you could post the make/model as some of these "smart" pumps can be configured in different ways, ie just like the old pump on a fixed speed setting or on differential pressure control or on constant pressure control, you want is to achieve a setting which will give the maximum possible flow rate but just below the "pitching" level and this should certainly be possible with the pump you have now installed.

Sleeper12

Wearb wrote: »

I am not one of the nicer mods and if you had answered anyone else like that I would have cautioned you, but seeing that your second paragraph made sense, no caution this time.

I wouldn't comment on a mod ruling but as this isn't I thought I'd fix your post. :cool:

swarlb

John.G wrote: »

It would be a big help if you could post the make/model as some of these "smart" pumps can be configured in different ways, ie just like the old pump on a fixed speed setting or on differential pressure control or on constant pressure control, you want is to achieve a setting which will give the maximum possible flow rate but just below the "pitching" level and this should certainly be possible with the pump you have now installed.

It's a Wilo, but I don't know the model. I have the old box somewhere, I'll look later. All I know it that it's one of the higher rated models.
My plumber is away for Christmas.

anthonyos

Could be a faulty stat on the immersion element I suppose it's a case of asking what's on at the time when it's happening

jimf

Sleeper12 wrote: »

I wouldn't comment on a mod ruling but as this isn't I thought I'd fix your post. :cool:

guess whos getting the bottle of sloe gin this year :P:P:P

Wearb

jimf wrote: »

guess whos getting the bottle of sloe gin this year :P:P:P

I did so much faffing around about making it this year that herself eventually threw out the sloes, so less exotic beverages this year. :pac::pac::pac:

John.G

anthonyos wrote: »

Could be a faulty stat on the immersion element I suppose it's a case of asking what's on at the time when it's happening

If it is then (and a good guess) then he may have a hot water flushed upstairs toilet and hot water from his cold gravity fed cold water taps as the hot water cylinder vent goes into the "big" tank and a failed immersion can sometimes set up a circulating flow with nasty consequences so it should be checked out ASAP.
A runaway 2/3 Kw immersion is no joke.

Wearb

John.G wrote: »

If it is then (and a good guess) then he may have a hot water flushed upstairs toilet and hot water from his cold gravity fed cold water taps as the hot water cylinder vent goes into the "big" tank and a failed immersion can sometimes set up a circulating flow with nasty consequences so it should be checked out ASAP.
A runaway 2/3 Kw immersion is no joke.

He has the immersion heater turned off for the winter (and it isn't getting power) because he leaves the coil in circuit during the winter. It's a well (factory) insulated cylinder and he prefers it that way.



We got a good list of the possible causes, which will be good to keep in mind. I suspect an intermittent problem with the boiler stat because at one stage while I was there it failed to click when being turned up and down, but afterwards continued to click. Besides I have ruled out all the other suggestions above. I am going to try and change it tomorrow if I get a break in the weather.

---

btw Turbohymac you seem to have knowledge about heating and plumbing; you should consider contributing more often (politely ) to this forum.

John.G

Wearb wrote: »

He has the immersion heater turned off for the winter (and it isn't getting power) because he leaves the coil in circuit during the winter. It's a well (factory) insulated cylinder and he prefers it that way.



We got a good list of the possible causes, which will be good to keep in mind. I suspect an intermittent problem with the boiler stat because at one stage while I was there it failed to click when being turned up and down, but afterwards continued to click. Besides I have ruled out all the other suggestions above. I am going to try and change it tomorrow if I get a break in the weather.

---

btw Turbohymac you seem to have knowledge about heating and plumbing; you should consider contributing more often (politely ) to this forum.

Boiler stat is a possibility alright as it may not be operating until = or > 100C but the temperature may still not have reached the 110/115C hi limit stat lockout. One would think that the cylinder hot water would be scaldingly hot as well though but not if its controlled by a cylinder stat.
Pitching?? as suggested above, I have never seen it myself but would not hot water pitching at say 65/75C cause "steam" to form as well?.

Wearb

John.G wrote: »

Boiler stat is a possibility alright as it may not be operating until = or > 100C but the temperature may still not have reached the 110/115C hi limit stat lockout. One would think that the cylinder hot water would be scaldingly hot as well though but not if its controlled by a cylinder stat.
Pitching?? as suggested above, I have never seen it myself but would not hot water pitching at say 65/75C cause "steam" to form as well?.

Yes it would. He did describe the DHW as very hot. Not controlled by a stat. No zone valves anywhere.

There does seem to be a difference in the reaction of the boiler stat to turning the knob that different than that caused by the fluid expansion in the phial. I suppose the much slower action allows the stat to stick for a while.

jimf

what make of boiler if its a warmflow it will most likely be a coltherm stat and they do give intermittent problems

there was also a few years back a batch of imit stats doing the rounds that wer dodgy

Wearb

jimf wrote: »

what make of boiler if its a warmflow it will most likely be a coltherm stat and they do give intermittent problems

there was also a few years back a batch of imit stats doing the rounds that wer dodgy

FB Heatpac S 90

jimf

they had a reputation for tripping the hl stat because of the configuration of the pipework from the boiler


but a pump over run which was supplied by fb fixed that problem once fitted

John.G

jimf wrote: »

they had a reputation for tripping the hl stat because of the configuration of the pipework from the boiler


but a pump over run which was supplied by fb fixed that problem once fitted

I have a 90S configured (nozzle) to a 70 (20 KW) and my manual recommends fitting a over run "where the pipe turns down" to the heating system which of course it does in all heatpac boilers but I don't/never had any hi limit stat problems (stat @ 75C), however with the advent of these A rated smart circ pumps it will be definitely become more of an issue as these pumps,especially when on proportional pressure (PP) control are mean and lean with their water flows and will IMO trip the Hi Limit stat more now than just occasionally if the hot water zone only is i/s. It will be far less of a issue with gas fired as these boilers modulate whereas the oil is firing at 20 to 36Kw at all times. If I was installing a new oil fired boiler now with zoning etc I would definitely recommend the fitting of a over run and auto by pass.

The stat fitted to my 13 year old is a IMIT, I think someone told me sometime that Grant use/used them as well?.

jimf

imit stats are the stat of choice by both grant and fb

grant did move to coltherm for a while back a few years ago as I think the imit quality wasn't up to scratch


but they are back using imit again