Issue with solid fuel stove connected to Systemlink

17-01-2016 05:18PM

John T Carroll wrote: »

That's why Hazops are now done routinely by a team to arrive at a acceptable risk.

I haven't heard of Hazpops, who is that?

John T Carroll · 17-01-2016 05:29PM

gary71 wrote: »

I haven't heard of Hazpops, who is that?

If you are building something or installing a piece of machinery in a plant, say a gas turbine, a team of people is tasked to look at any potential risks while installation is going on and ease of operation and overhaul etc after its installed.

HAZOP stands for Hazard and Operational Study

my3cents · 17-01-2016 06:09PM

I don't think anyone asked the OP what they meant by "Systemlink" a quick google comes up with this product the Systemlink Heat Genie (don't you just know its going to work by magic

). So how would you guys feel about using this in the OP's senario?

My thoughts are if the power goes in a lot of Irish bungalows then so does the private water supply so the first safety measure won't work. As for the last ????

Dtp1979 · 17-01-2016 07:27PM

my3cents wrote: »

I don't think anyone asked the OP what they meant by "Systemlink" a quick google comes up with this product the Systemlink Heat Genie (don't you just know its going to work by magic ). So how would you guys feel about using this in the OP's senario?

My thoughts are if the power goes in a lot of Irish bungalows then so does the private water supply so the first safety measure won't work. As for the last ????

Me personally, I wouldn't use one if I got it for free

John T Carroll · 17-01-2016 08:00PM

Dtp1979 wrote: »

Me personally, I wouldn't use one if I got it for free

You would want to be a Genie to understand it, I must have another peep at it.

John T Carroll · 17-01-2016 08:18PM

my3cents wrote: »

I don't think anyone asked the OP what they meant by "Systemlink" a quick google comes up with this product the Systemlink Heat Genie (don't you just know its going to work by magic ). So how would you guys feel about using this in the OP's senario?

My thoughts are if the power goes in a lot of Irish bungalows then so does the private water supply so the first safety measure won't work. As for the last ????

Thats a good link to it, all you need for the first measure to work is to run a cheap 50 mile mains run from the nearest town and in the last measure you "douse" the fire (bucket of water or a wet blanket?)......Safety?????

Dtp1979 · 17-01-2016 08:20PM

John T Carroll wrote: »

Thats a good link to it, all you need for the first measure to work is to run a cheap 50 mile mains run from the nearest town and in the last measure you "douse" the fire (bucket of water?)......Safety?????

Ye my thinking too. They say you can use a storage tank of water in the attic either. My biggest issue is the valve becoming faulty in a few years

17-01-2016 08:30PM

G3 regs and cylinder manufacturers instructions require a spring return (spring closed) motorised valve fitted on the flow pipe feeding the cylinder which is then controlled by a cylinder thermostat.

System link use pumps instead of MV, as you can at times get movement across a pump that's switched off I've never liked systemlink, but the few systemlink systems (not heat genie) I've seen do work well.

Dtp1979 · 17-01-2016 08:33PM

gary71 wrote: »

G3 regs and cylinder manufacturers instructions require a spring return (spring closed) motorised valve fitted on the flow pipe feeding the cylinder which is then controlled by a cylinder thermostat.

System link use pumps instead of MV, as you can at times get movement across a pump that's switched off I've never liked systemlink, but the few systemlink systems (not heat genie) I've seen do work well.

A MV on the primary circuit of solid fuel?

John T Carroll · 17-01-2016 08:33PM

Dtp1979 wrote: »

Ye my thinking too. They say you can use a storage tank of water in the attic either. My biggest issue is the valve becoming faulty in a few years

That valve with the capillary is called a tapstat I think, I know this isnt connected to safety but they are now illegal or at least very hard to get when you want to use them instead of a motorised valve to control the hot water cylinder temperature, something to do with the fact that they only operate by proportional control (obviousy) and cant guarantee a constant 60C. In my (old) days they were used extensively for all sorts of control and were very effective and I cant recall any problems with them.

John T Carroll · 17-01-2016 08:37PM

Dtp1979 wrote: »

A MV on the primary circuit of solid fuel?

Please dont start another thread or I'll never get out tonight!!.

Dtp1979 · 17-01-2016 08:37PM

John T Carroll wrote: »

That valve with the capillary is called a tapstat I think, I know this isnt connected to safety but they are now illegal or at least very hard to get when you want to use them instead of a motorised valve to control the hot water cylinder temperature, something to do with the fact that they only operate by proportional control (obviousy) and cant guarantee a constant 60C. In my (old) days they were used extensively for all sorts of control and were very effective and I cant recall any problems with them.

Sorry I was talking s out the safety valve that opens and cools the boiler if it overheats

John T Carroll · 17-01-2016 08:41PM

Dtp1979 wrote: »

Sorry I was talking s out the safety valve that opens and cools the boiler if it overheats

I understand that and I wouldnt have any problem from that aspect of things

Dtp1979 · 17-01-2016 08:47PM

John T Carroll wrote: »

I understand that and I wouldnt have any problem from that aspect of things

You reckon they'd be no issue of the valve sticking in years to come with sludge or whatever?

John T Carroll · 17-01-2016 08:55PM

Dtp1979 wrote: »

You reckon they'd be no issue of the valve sticking in years to come with sludge or whatever?

Cant look into the future just yet,another example of acceptable risk where safety is concerned?, this whole safety system to me looks very suspect and who is going to put a header tank in the "attic" if one has no mains suppy?

17-01-2016 09:20PM

Dtp1979 wrote: »

A MV on the primary circuit of solid fuel?

Nope, you can't connect stoves to a unvented cylinder:)

As for the performance of controls on a unvented cylinder it tends to be forgotten that unvented cylinders require yearly safety checks and cylinders require a tundish to indicate failures like MV or expansion vessel.

John T Carroll · 21-01-2016 10:03AM

gary71 wrote: »

Nope, you can't connect stoves to a unvented cylinder:)

As for the performance of controls on a unvented cylinder it tends to be forgotten that unvented cylinders require yearly safety checks and cylinders require a tundish to indicate failures like MV or expansion vessel.

Realistically, its hard to imagine the majority of domestic unvented cylinder owners doing the above, human nature being what it is, bearing this in mind the thermal store route seems increasingly attractive?.
I read a few bits and pieces re the current G3 requirements which Irish regulations will eventually probably mirror, if they already havn't. G3 seems to be saying that irrespective of the heat sources employed, that the hot water cylinder temperature cannot be greater than 89C/90C by using the "usual" safety devices but additionally they now specify a "high energy" cut out (set at 89C) which will shut off all indirect heat inputs, ie oil/gas boiler. What is not quite clear to me is to whether they also stipulate a interposing/iolating relay in the supply to the Immersions and dont just rely on the Immersions normal and hi limit stats. If this is in fact the way they do it (regarding the Immersions) then I would be very happy as in my opinion immersion heating "gone wrong" is potentially far more dangerous than having a vented solid fuel source feeding a unvented hot water cylinder for the reasons I have given previously, ie the temperature cannot exceed 102C/105C.
Below is a quote from literature from a Megaflow unvented Hot water Cylinder.

"Safety controls protect the householder (or users), and ensures the water temperature never exceeds 99°C. These are absolutely essential and they must be in good working order. They usually comprise the following:- Control thermostat which is typically set at between 60 and 65°C. High level, energy cut out device with manual re-set, usually set between 85 and 89°C. Temperature and Pressure Relief Valve set to 90 - 95°C or 10 bar pressure. Expansion relief valve set to 8 bar pressure. Additionally, the two electrical thermostats (control and high level) and wired into a motorised valve such that any indirect heat source will be shut-off"

Wearb · 21-01-2016 11:18AM

Those controls would be a great improvement to the overall safe operation.
Biggest problem is that plumbers are putting these unvented cylinders (and boiler stoves) in and not emphasising the potential danger to the house and occupants.

My daughter is in an now 2.5 year old house. She and especially her husband think that I am being alarmist when I explain what could happen. They just say the plumber is well qualified and has done loads of new houses in the area. He never mentioned getting it serviced, or the dangers of device failure.
Their answers are typical of all the houses where I do boiler servicing. I suppose the fact that there are so few accidents here (due to first line safety devices working) leads to this complacency.

John T Carroll · 21-01-2016 01:25PM

Wearb wrote: »

Those controls would be a great improvement to the overall safe operation.
Biggest problem is that plumbers are putting these unvented cylinders (and boiler stoves) in and not emphasising the potential danger to the house and occupants.

My daughter is in an now 2.5 year old house. She and especially her husband think that I am being alarmist when I explain what could happen. They just say the plumber is well qualified and has done loads of new houses in the area. He never mentioned getting it serviced, or the dangers of device failure.
Their answers are typical of all the houses where I do boiler servicing. I suppose the fact that there are so few accidents here (due to first line safety devices working) leads to this complacency.

Correct, but you have to try and design safety devices away from people which is what G3 or equivalent is trying to do, you might say next step is to ban all domestic unvented hot water cylinders but one wouldnt be too popular for suggesting this and you will be told that they represent a acceptable risk and that we are constantly looking at methods to further reduce this risk.
Have a read of the following sometime which shows how all the holes in the swiss cheese can line up, the reason I knew/know about it is that a very conscientious young fishing skipper that I knew used to tie up next to this boat occasionally and he me asked to explain exactly how this could have happened.
https://assets.digital.cabinet-office.gov.uk/media/547c714ced915d4c100000f3/fleur-de-lys.pdf

Wearb · 21-01-2016 04:04PM

Just had a read of it.

No PRV
Ignored owners advice to turn off power to immersion
Plumber on land gave advice assuming prv fitted.
Previous warning signs ignored.

Incorrect cylinder fitted, but seeing what happened, that may have saved their lives.

21-01-2016 10:15PM

You don't ban unvented cylinders you ban incorrectly unvented cylinders, any appliance that poses a risk to a home owners should be shut down until it's fitted properly.

If a unvented cylinder is fitted correctly the worst that will happen is the safety valve lifts and passes water/steam into a pipe designed to carry it which then terminates in a safe manor.

Unvented cylinders aren't rocket science but must be respected, nearly every cylinder I've tested here by manually opening the T/P have backed up and overflowed at the Tundish.

Having been around unvented cylinders for many years you get usually get a service call to a correctly installed cylinder long before most issues become a dramatic problem.

21-01-2016 10:23PM

John T Carroll wrote: »

Realistically, its hard to imagine the majority of domestic unvented cylinder owners doing the above, human nature being what it is, bearing this in mind the thermal store route seems increasingly attractive?.
I read a few bits and pieces re the current G3 requirements which Irish regulations will eventually probably mirror, if they already havn't. G3 seems to be saying that irrespective of the heat sources employed, that the hot water cylinder temperature cannot be greater than 89C/90C by using the "usual" safety devices but additionally they now specify a "high energy" cut out (set at 89C) which will shut off all indirect heat inputs, ie oil/gas boiler. What is not quite clear to me is to whether they also stipulate a interposing/iolating relay in the supply to the Immersions and dont just rely on the Immersions normal and hi limit stats. If this is in fact the way they do it (regarding the Immersions) then I would be very happy as in my opinion immersion heating "gone wrong" is potentially far more dangerous than having a vented solid fuel source feeding a unvented hot water cylinder for the reasons I have given previously, ie the temperature cannot exceed 102C/105C.
Below is a quote from literature from a Megaflow unvented Hot water Cylinder.

"Safety controls protect the householder (or users), and ensures the water temperature never exceeds 99°C. These are absolutely essential and they must be in good working order. They usually comprise the following:- Control thermostat which is typically set at between 60 and 65°C. High level, energy cut out device with manual re-set, usually set between 85 and 89°C. Temperature and Pressure Relief Valve set to 90 - 95°C or 10 bar pressure. Expansion relief valve set to 8 bar pressure. Additionally, the two electrical thermostats (control and high level) and wired into a motorised valve such that any indirect heat source will be shut-off"

The high limit stat on immersion is all that's used.

You can't connect a uncontrollable heat source to a unvented cylinder it impacts on home insurance and manufacturers warranty unlike a immersion failing which is covered, when a T/P lifts due to a failed stat the temperature in the cylinder will drop much quicker while dealing with a 3kw immersion than it would with a 25-30 kW coil.

21-01-2016 10:33PM

Wearb wrote: »

Those controls would be a great improvement to the overall safe operation.
Biggest problem is that plumbers are putting these unvented cylinders (and boiler stoves) in and not emphasising the potential danger to the house and occupants.

My daughter is in an now 2.5 year old house. She and especially her husband think that I am being alarmist when I explain what could happen. They just say the plumber is well qualified and has done loads of new houses in the area. He never mentioned getting it serviced, or the dangers of device failure.
Their answers are typical of all the houses where I do boiler servicing. I suppose the fact that there are so few accidents here (due to first line safety devices working) leads to this complacency.

Thankfully unvented cylinders going bang are very rare but what I do see is homes being destroyed by water damage due to safety valves lifting then pumping mains water into the home. When this happens insurance companies and manufacturers walk away as the cylinder is not fitted asper MI, if the home owner is lucky they can go after the installer who could get caught for tens of thousands for not reading the MI which does come with colour pictures.

John T Carroll · 21-01-2016 10:37PM

gary71 wrote: »

As for the performance of controls on a unvented cylinder it tends to be forgotten that unvented cylinders require yearly safety checks and cylinders require a tundish to indicate failures like MV or expansion vessel.

gary71 wrote: »

Having been around unvented cylinders for many years you get usually get a service call to a correctly installed cylinder long before most issues become a dramatic problem.

Your first quote above states that unvented cylinders require yearly safety checks, who ensures that this happens? and is it mandatory on domestic systems?. I would be very surprised if many home owners would call in anybody to do a yearly safety check if there was no apparent sign of water leakage or whatever.

21-01-2016 10:57PM

John T Carroll wrote: »

Your first quote above states that unvented cylinders require yearly safety checks, who ensures that this happens? and is it mandatory on domestic systems?. I would be very surprised if many home owners would call in anybody to do a yearly safety check if there was no apparent sign of water leakage or whatever.

In the UK the home owner generally takes more ownership for home heating controls and are usually more aware of a tundish and what it signifies also cylinder checks are looked for by home owners to maintain their warranty, safety checks are usually simply incorporated into a yearly boiler service as boiler service engineers in the UK can include the whole home heating system in a service and not just boiler specific as it tends to be in Ireland.

Wearb · 22-01-2016 01:43AM

@Gary. Unless I am misled, boiler service in the UK rarely includes whole heating service. Can do, but not common.

I think the knowledge about tun dishes and the implications of water appearing there is down to plumbers supplying customers with the proper info. Perhaps there is a part to be played by insurance companies here also.

I accept your point about flooding from badly installed prv outlets. When that happens with most current installs, it is last line defence. Btw, I rarely see tun dishes. It's either a drum or piped back into the attic and out into the gutter. Maybe that's just around here. I don't have a broad geographical knowledge of this.

Good to hear your experienced opinion on these matters Gary. My questions are in no way meant to belittle your experience, but improve my knowledge and perhaps pass it on afterwards.

Dtp1979 · 22-01-2016 08:22AM

Wearb wrote: »

I accept your point about flooding from badly installed prv outlets. When that happens with most current installs, it is last line defence. Btw, I rarely see tun dishes. It's either a drum or piped back into the attic and out into the gutter. Maybe that's just around here. I don't have a broad geographical knowledge of this.

In my area, they're usually piped into the clothes in the hotpress

John T Carroll · 22-01-2016 08:38AM

Wearb wrote: »

I accept your point about flooding from badly installed prv outlets. When that happens with most current installs, it is last line defence. Btw, I rarely see tun dishes. It's either a drum or piped back into the attic and out into the gutter.

If the discharge from the PRV is piped then you still need a telltale hole at the bottom of the discharge and a tundish, apart from its telltale function its also important to keep any build up of condensate fully drained as its often been the cause of PRVs seizing up due to the build up of rust/crap. All the Boiler PRVs (Safety Valves) that I maintained had their discharges to atmosphere, they had to as they were lifting at around 50 Bar and I had a monthly routine where these telltales were checked for blockages.
Its just an opinion but I would much prefer to see a properly tundished set up on a domestic cylinder but this might not be practiceable due to confined spaces etc.

22-01-2016 09:46AM

John T Carroll wrote: »

If the discharge from the PRV is piped then you still need a telltale hole at the bottom of the discharge and a tundish, apart from its telltale function its also important to keep any build up of condensate fully drained as its often been the cause of PRVs seizing up due to the build up of rust/crap. All the Boiler PRVs (Safety Valves) that I maintained had their discharges to atmosphere, they had to as they were lifting at around 50 Bar and I had a monthly routine where these telltales were checked for blockages.
Its just an opinion but I would much prefer to see a properly tundished set up on a domestic cylinder but this might not be practiceable due to confined spaces etc.

Doesn't matter if it's a 10ltr undersink or a 500ltr floor standing all unvented appliances require a tundish, they must be fitted, installers choose to ignore safety requirements for these appliances as there is no enforcement.

22-01-2016 10:00AM

Wearb wrote: »

@Gary. Unless I am misled, boiler service in the UK rarely includes whole heating service. Can do, but not common.

I think the knowledge about tun dishes and the implications of water appearing there is down to plumbers supplying customers with the proper info. Perhaps there is a part to be played by insurance companies here also.

I accept your point about flooding from badly installed prv outlets. When that happens with most current installs, it is last line defence. Btw, I rarely see tun dishes. It's either a drum or piped back into the attic and out into the gutter. Maybe that's just around here. I don't have a broad geographical knowledge of this.

Good to hear your experienced opinion on these matters Gary. My questions are in no way meant to belittle your experience, but improve my knowledge and perhaps pass it on afterwards.

I'v never understood how a fella can service a boiler but not understand or work on the wet side, what's the point of servicing a boiler but not bleeding a rad or checking the nonreturn valve.

Traditionally in the UK a boiler service would automatically include the whole heating system so anybody working on boilers would check everything, room stats, rads, rad valves, MV, cylinder stat, hot water temp, F/E tank etc... so you will find most RGI will still check the basics as a given its only the big companies with a harem of poorly paid workers that have introduced pointless boiler only services.

Anyone with a unvented cylinder in the UK simple gets a RGI with G3 accreditation who will do the cylinder as well as the boiler.

Issue with solid fuel stove connected to Systemlink

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