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Firstly hello, i did a quick search and wasn't sure whether this should be in here or the central heating section so if i've got it wrong i apologies!

We are looking to replace our current vented system with an unvented indirect 210l cylinder to replace the current pump used for two deluge showers and the bath. Main reason for change is the noise and due to the way it was installed the pump struggles to provide the pressure. Its worth adding we have great cold water mains pressure.

So we've been looking at numerous cylinders and the prices vary greatly! I have seen a Sapphire cylinder which i believe are made by Heatrae Sadia but maybe someone could confirm that? this cylinder is cheap in comparison so wondered if anyone has any experience as to whether these are any good? my concern is i dont want to purchase something because its cheaper and it end up not being fit for purpose, but on the same note dont want to spend more if it is not required...

Greatful for any advice for alternative options to consider. Thanks in advance.
 
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Sorry dont know anything about sapphire cylinder , one of the best cylinders out there is a Tribune , an ultrasteel ( cheaper ) is a tribune with different badges.
IMO of course
 
Hi thank you for the reply.

I've taken a look at what you recommended thank you and will certainly keep them in mind the ultrasteel works out around the £570 mark whereas the Sapphire is around the £420 mark. I'm a firm believer that generally you pay for what you get but if i am correct that it is a Heatrae Sadia Premier plus are these not a good brand?

As i say open to any suggestions. Thanks
 
my concern is i dont want to purchase something because its cheaper and it end up not being fit for purpose, but on the same note dont want to spend more if it is not required...

Are you aware that unvented DHW systems are tightly regulated and you need an engineer who is qualified 'G3 unvented' to install the cylinder? You should get two or three local firms to quote for the work and discuss the pros and cons with them.
 
Are you aware that unvented DHW systems are tightly regulated and you need an engineer who is qualified 'G3 unvented' to install the cylinder? You should get two or three local firms to quote for the work and discuss the pros and cons with them.

Hi Yes I am, I'm not intending to fit it myself I have a friend that is a qualified installer and has his own business. He doesn't mind whether i get one myself or he can provide one. He suggested a Joule, but the Sapphire is cheaper hence the reason for me trying to understand if they are going to fulfill the purpose.

Thanks
 
No they are ok, Premier plus !!

Hi Townfanjon, thank you again for the reply. Could i just ask you please, so assuming i can get confirmation that the Sapphire is in fact the premier plus from Heatrae Sadia then are you saying this should be a good purchase?

Thanks
 
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Big differences between the cheap, mid range and best.
Some of the cheapest are made of steel, which is then enamelled. These can get pin holed very easily.
Also the cheaper end have poor recovery times, as they have smaller coils.
ACV and Joule are among the best.
Premier plus and Rm are fully stainless and have a good pressure reducing set and expansion vessel.
 
Big differences between the cheap, mid range and best.
Some of the cheapest are made of steel, which is then enamelled. These can get pin holed very easily.
Also the cheaper end have poor recovery times, as they have smaller coils.
ACV and Joule are among the best.
Premier plus and Rm are fully stainless and have a good pressure reducing set and expansion vessel.

Hi Chalked, I cant believe how helpful everyone is on here its great! thank you for your reply.

So do you think for the extra £150 the Joule would perform better than the Sapphire branded premier plus?

Thanks
 
Joule or gledhill yes worth the extra
 
Hi Townfanjon, thank you again for the reply. Could i just ask you please, so assuming i can get confirmation that the Sapphire is in fact the premier plus from Heatrae Sadia then are you saying this should be a good purchase?

Thanks
Honestly cant say , but what has happened over the last few years is the manufacturers have their flagship cylinder and then also make a budget cylinder as well
 
Joule or gledhill yes worth the extra

Hi ShaunCorbs, thank you for the reply. I think you have answered my question then.
Honestly cant say , but what has happened over the last few years is the manufacturers have their flagship cylinder and then also make a budget cylinder as well

Oh I think I see what you are saying. To me it looked identical other than the premier has 30 years warranty and the sapphire has 10 years, same dimensions, stainless steel etc but i assume what your saying is that they’re probably not made of the same material
 
Hi Yes I am, I'm not intending to fit it myself I have a friend that is a qualified installer and has his own business. He doesn't mind whether i get one myself or he can provide one. He suggested a Joule, but the Sapphire is cheaper hence the reason for me trying to understand if they are going to fulfill the purpose.

Thanks

That sends me a warning shot. If he's fully competent, then he should be advising you on an appropriate cylinder and indeed whether your property is suitable. Suggest you find someone with a lot more nouse than your pal and get some professional advice. We simply cannot do that as we can't measure and assess suitability - especially with your 'deluge' system.

Good luck.
 
That sends me a warning shot. If he's fully competent, then he should be advising you on an appropriate cylinder and indeed whether your property is suitable. Suggest you find someone with a lot more nouse than your pal and get some professional advice. We simply cannot do that as we can't measure and assess suitability - especially with your 'deluge' system.

Good luck.

Hi YorkshireDave, I don't wish to come across rude and ungrateful for the advice but I am a little confused by your reasons for the animosity and sarcasm? Is deluge the incorrect terminology?

My friend is more than competent and as previously stated he has advised a Joule cylinder, he has also said that although he has never heard of the sapphire cylinder if it is indeed a heatrae Sadia that I think I have read somewhere then he thinks that would be sufficient as well.

I have come on to a forum like this merely for a second opinion, some friendly advice and to weigh up whether the cost saving of the sapphire cylinder over something like the joule would be worth it in the long run, or whether the penny pinching would provide an underperforming system and I apologies if this has offended you in some way?

Thanks.
 
I am with Shuan on this one Gledhill or joule I have 2 to do in the near future and am planning on using the Gledhill I had a quote on them on a trade day at my local supplier and they were very competitive , Heatrea are ok bud beware the warranty may not be honoured I had a pin holed shell on a 10year old megaflo supposed to be 25years on the shell wouldn't do anything about it so since then I have not fitted them . Cheers kop
 
I'd look at the recovery times and always go for stainless as @Chalked said enameled cylinders are trouble.
Also some cylinders say in manual that they need de-scaling annually which isn't economical and i'm sure it's just a way for manufacturer to get away with not honouring the guarantee.
30 years is a good guarantee for a cylinder and might be usefull, on the other hand if you need a 10 year guarantee on a stainless cylinder then you should be very worried about year 11,12,13....
 
Thank you for all the replies they have been very helpful.

I will need to speak to my friend and find out which Joule cylinder he was recommending as they do one with 10 years and one with 25 years warranty from what i can see, but from the responses i have had I think the general consensus is no one has heard of or used the Sapphire (which isnt a good sign) and the Joule brand has come up a number of times.

Thanks
 
you mentioned great water pressure!
Has this actually been checked? Pressure is not the only important thing with the set up you’re suggesting. Flow rates are! Likely incoming main was piped up in 15mm/ to feed a tank. Are you confident that when the new cylinder is fitted there will be sufficient flow rates to adequately supply the appliamces in question?
You need 18-20l per min.
 
you mentioned great water pressure!
Has this actually been checked? Pressure is not the only important thing with the set up you’re suggesting. Flow rates are! Likely incoming main was piped up in 15mm/ to feed a tank. Are you confident that when the new cylinder is fitted there will be sufficient flow rates to adequately supply the appliamces in question?
You need 18-20l per min.

Hi,

Thank you for the reply, no it hasn't been checked yet and you're correct it is 15mm from the incoming feed to the tank.

The flow rate out the upstairs taps seems very fast / strong out of modern taps that require minimum 1 bar but my friend needs to come found and check the pressure and that the boiler (suprema 50) are both suitable.

I was going to do the bucket test but I may as well let him check it properly, although I don't foresee an issue.

Thanks
 
Again pressure is a little bit of a red herring in my opinion. Most dwellings will get at least 1bar coming into the property. But you could have 20bar if the flow rate is being restricted enough the high pressure will only last for a few secs when multiple outlets are I use.

Get your friend to test the water flow rate from the cold pipe connection that is going to feed the cylinder (before the ball/float valve) and also carry out a working test (so with other mains cold taps open (kitchen sink cold tap ) testing from any other point may yield a false positive as it is from this point that you’ll feed the hot supply. As stated most invented cylinder advise on 18-20l/min
 
Again pressure is a little bit of a red herring in my opinion. Most dwellings will get at least 1bar coming into the property. But you could have 20bar if the flow rate is being restricted enough the high pressure will only last for a few secs when multiple outlets are I use.

Get your friend to test the water flow rate from the cold pipe connection that is going to feed the cylinder (before the ball/float valve) and also carry out a working test (so with other mains cold taps open (kitchen sink cold tap ) testing from any other point may yield a false positive as it is from this point that you’ll feed the hot supply. As stated most invented cylinder advise on 18-20l/min

Hi thank you for the advice I will ask him to do that before making any final decision.

Could I ask another question other than what I have at the minute (noisy pump) I am correct in saying that my only options are an unvented cylinder or a combi boiler aren't I?

Am pretty convinced the pressure will be ok but just asking in case there's a problem? Or there's a better solution

Thanks
 
I cant repeat this enough, pressure is NOT the key... it’s flow rates changing a cylinder is expensive work so ignore that at your peril...

modern pumps are a lot quieter. How old is the current one may be a better option to consider upgrading. If not or the pump is relatively new (less than 5 years) and of a quality brand (Stuart turner, Salamder to name a few) has it been installed correctly?
Could you dampen the noise? Check the feet have they got the insulating pads on? What surface is it on? could you put some cushioning under it to dampen the noise?, can you sound proof the area. There are always options mate just need to think outside the box a little...
 
Firstly Robsterno1, don't get drawn into replies with those that choose to post less than helpful responses. This has happened to me before in the past when seeking, as is in your case, some genuine helpful advice. Annoying though it is, it just offers 'grist to the mill', so if on here again just refrain and ignore. That's what I do and I'm Gas Safe registered and G3 qualified.

That being said you may wish to consider the more helpful responses that were given. Notably, Joule over some brand that no-one has heard of. In my business I offer my customers several cost options ranging from entry level RM's up to Joule or Gledhill cylinders. I also offer them the option of a dual coil cylinder which will facilitate a very fast recovery time when both coils connected to a single heat source. Where, the secondary coil can be connected to an ASHP (Air Source Heat Pump) or Solar Thermal IF the customer should so desire to install one at a later stage. Obviously, a single coil cylinder will be cheaper to purchase than a dual coil one.

I agree with the opinion expressed about staying away from enamelled cylinders. Obsolete technology in my opinion that should be avoided.

In general, with regards to the domestic unvented cylinder market, the more expensive the cylinder is the more likely it has been manufactured from a superior grade of Duplex stainless steel. There exists three main grades of Duplex S/S: Lean, Reference (sometimes known as Standard) and Super, respectively. All of which have there specific commercial applications and now more widely employed by cylinder manufactures. I suspect, but can not be clear as no manufacturer is willing to divulge this commercially sensitive information when I made my own enquiry some time ago, that the cheaper cylinders are made from Lean grade Duplex and the more expensive from Reference (or standard) grade Duplex. The later having a higher Molybdenum content which in turn gives a greater overall resistance to chloride stress corrosion cracking. Thus the difference in manufacture warranties and price point.

In addition, as helpful contributors have remarked, water pressure is not the only consideration in this instance when upgrading to an unvented cylinder. The flow rate (volume of water/unit time) is important too and is directly related to the cross sectional area of your incoming mains water supply pipe. Your friend, should undertake a dynamic pressure test and flow rate at the nearest unrestricted draw off point to the internal stopcock to quantify this. Rule of thumb is approx. 20L/min at 2bar. Consequently, will an upgrade to your mains water supply need to be undertaken? Inside the house? Outside the house? Or both?

It would not be unreasonable to ask your friend to detail a schematic of that which is proposed and then if you wished for it to be reviewed by useful contributors on here I'm sure you will get some helpful feedback.

Other points to note, when converting over your domestic hot water set up, is the potential risk for component failure due to the higher standing water pressure as a consequence of the hot and cold services now being pressurised to a maximum of 3bar. Where as before, notwithstanding anything in your current set up that was served directly off of the mains, would have a standing pressure of approximately 0.5bar.....dependant of course on the height of the cold water storage tank in your loft above the outlets it serves.

In addition, and a point I posted on not that long ago, is the need for the plumber to ensure a balanced hot and cold draw off through out the house. Therefore, ask him what aspects of the existing plumbing will remain and what will change to being served by a balanced supply.

Lastly, consider location. As it is proposed to install a mains fed cylinder this can, within reason, be at any location in the house, notwithstanding D2 termination requirements. This being a term that if he's G3 registered he will be able to explain and discuss with you.

These are all basic design elements that through good practice and communication with your customer can be discussed and decided upon before the commencement of works. Informed choice!

Hope this helps in some way.
 
Firstly Robsterno1, don't get drawn into replies with those that choose to post less than helpful responses. This has happened to me before in the past when seeking, as is in your case, some genuine helpful advice. Annoying though it is, it just offers 'grist to the mill', so if on here again just refrain and ignore. That's what I do and I'm Gas Safe registered and G3 qualified.

That being said you may wish to consider the more helpful responses that were given. Notably, Joule over some brand that no-one has heard of. In my business I offer my customers several cost options ranging from entry level RM's up to Joule or Gledhill cylinders. I also offer them the option of a dual coil cylinder which will facilitate a very fast recovery time when both coils connected to a single heat source. Where, the secondary coil can be connected to an ASHP (Air Source Heat Pump) or Solar Thermal IF the customer should so desire to install one at a later stage. Obviously, a single coil cylinder will be cheaper to purchase than a dual coil one.

I agree with the opinion expressed about staying away from enamelled cylinders. Obsolete technology in my opinion that should be avoided.

In general, with regards to the domestic unvented cylinder market, the more expensive the cylinder is the more likely it has been manufactured from a superior grade of Duplex stainless steel. There exists three main grades of Duplex S/S: Lean, Reference (sometimes known as Standard) and Super, respectively. All of which have there specific commercial applications and now more widely employed by cylinder manufactures. I suspect, but can not be clear as no manufacturer is willing to divulge this commercially sensitive information when I made my own enquiry some time ago, that the cheaper cylinders are made from Lean grade Duplex and the more expensive from Reference (or standard) grade Duplex. The later having a higher Molybdenum content which in turn gives a greater overall resistance to chloride stress corrosion cracking. Thus the difference in manufacture warranties and price point.

In addition, as helpful contributors have remarked, water pressure is not the only consideration in this instance when upgrading to an unvented cylinder. The flow rate (volume of water/unit time) is important too and is directly related to the cross sectional area of your incoming mains water supply pipe. Your friend, should undertake a dynamic pressure test and flow rate at the nearest unrestricted draw off point to the internal stopcock to quantify this. Rule of thumb is approx. 20L/min at 2bar. Consequently, will an upgrade to your mains water supply need to be undertaken? Inside the house? Outside the house? Or both?

It would not be unreasonable to ask your friend to detail a schematic of that which is proposed and then if you wished for it to be reviewed by useful contributors on here I'm sure you will get some helpful feedback.

Other points to note, when converting over your domestic hot water set up, is the potential risk for component failure due to the higher standing water pressure as a consequence of the hot and cold services now being pressurised to a maximum of 3bar. Where as before, notwithstanding anything in your current set up that was served directly off of the mains, would have a standing pressure of approximately 0.5bar...dependant of course on the height of the cold water storage tank in your loft above the outlets it serves.

In addition, and a point I posted on not that long ago, is the need for the plumber to ensure a balanced hot and cold draw off through out the house. Therefore, ask him what aspects of the existing plumbing will remain and what will change to being served by a balanced supply.

Lastly, consider location. As it is proposed to install a mains fed cylinder this can, within reason, be at any location in the house, notwithstanding D2 termination requirements. This being a term that if he's G3 registered he will be able to explain and discuss with you.

These are all basic design elements that through good practice and communication with your customer can be discussed and decided upon before the commencement of works. Informed choice!

Hope this helps in some way.

mubesjnr thank you very much for such a detailed response. It is very much appreciated.

I need to sit down with my friend and go through everything and make sure he is going to check the flow rates and suitability before I commit to spending in the region of £1000 including the cylinder. Pretty convinced i've decided that the Joule tank is the better option should I move forward though.

Thanks
 
I cant repeat this enough, pressure is NOT the key... it’s flow rates changing a cylinder is expensive work so ignore that at your peril...

modern pumps are a lot quieter. How old is the current one may be a better option to consider upgrading. If not or the pump is relatively new (less than 5 years) and of a quality brand (Stuart turner, Salamder to name a few) has it been installed correctly?
Could you dampen the noise? Check the feet have they got the insulating pads on? What surface is it on? could you put some cushioning under it to dampen the noise?, can you sound proof the area. There are always options mate just need to think outside the box a little...

Thank you again for your reply,

The pump is a PTE (Grundfos) pump and is only 2 years old. It is in the airing cupboard and has rubber feet on it. Its not so much the vibrations its the noise of the pump thats the issue.

Due to the noise it makes we cant really shower once the children are in bed. Also it is only 1.5bar and as the plumber that did the work connected two showers and a bath to the outlet it struggles to provide suitable pressure to the en-suite shower, and sometimes i have to turn the power off with the shower on and back on again and even then we sometimes get jets firing all over the place!

A noise free, fully working solution would deffinately be preferred.

Thanks
 
If your friend is a decent G3 plumber then he will sort what is best for you.
Flow rates are most important
 
I would go with the Gledhill or a ThermaQ both are very good; both for longevity and heat recovery and middle of the market for price.
Heatrae Sadia are very expensive, they are the Rolls Royce of cylinders and if you have aggressive water or Private Supply they will give good service.
As for warranty across the board these companies will wriggle out of their liablity - they pay some very expensive people to write the T & C's!
 
Hi Gents, I'm a newly qualified installer and was wondering if you guys had any problems fitting these tanks with CWM feed flow rates below that stated by the manufactures.
I have a customer that would like to change to one of these from a vented system. The CWM has good pressure at the stopcock (4Bar)
but flow rate is 16 l/m at high demand. Most manufactures recommend a minimum of 1.5 Bar and 20 l/m flow rate.
The customer has 2 bathrooms and 3 on-suites.
Be good to know what you guys suggest.
 
Accumulator needs to be installed

Is that a 4 bar dynamic or static eg with an outlet open ?
 
An accumulator would be perfect then do you know how to size them ?
 
As Shaun says PDS an accumulator would be ideal for your situation, this will maximise working pressure and flow rates but do need to be sized properly or if it runs dry the working conditions will revert back to what you have now. Also and this is not the case now sometimes a charging pump is needed to boost flow but this is usually when incoming pressure and flow is very low. Upgrading pipework can also help in this situation depending on what the original carcass is but as Shaun said the accumulator will do. If an accumulator is sized correctly and installed correctly then there’s virtually no limit to the amount of appliances working from it. Although I have done my G3 in the past and done a few cylinders I can’t say what size is needed but I’m sure Shaun can advise as he said.
 

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