Hi, some professional advice would be greatly appreciated,
We are having an Unvented Cylinder installed into our 2 bedroom ground floor flat. I have had a few quotes and been given lots of differing advice, this always makes me wary, especially having suffered a history of poor quality work by cowboys in the past. Which is why I am here.
The question is in the title: What make of Direct Unvented Cylinder, and what size?
I am going to include all the information so that this thread can be of use to others with the same question.
I have had 3 quotes and 3 different cylinders suggested: Mega-Flo, evoCyl and Main. Everyone knows Mega, the other 2 are a mystery to me.
The specifics:
This is a two bed, one bathroom flat with a P shaped shower bath (similar to the one in the image below), so the bath takes a little more water than average to fill.
We currently have an ageing electric shower and a failing immersion heater and tank. Just barely 20L pm , and just barely 2 bar. Appalling pressure and flow from the current gravity system (ground floor). The flats are all electric, no gas. Almost all the plumbers agree that UC is the answer.
The boiler cupboard is right by the bathroom, as well as by the block of flats mains stopcocks, these have blue pipe, so I presume 25mm.
We are a couple with a 5 year old boy. So we tend to have on average 3 showers a day, although we can easily have a shower, a childs bath and an adult bath in one day. As my wife and I both like baths, sometimes (but not regularly) 2 baths in a day.
There is also a dishwasher and washing machine (I presume these only take cold from the mains).
We have E7 heating.
The electric shower will be replaced by a Mira Excel thermostatic shower, we are also getting a thermostatic bumgun.
Most plumbers have recommended 150 or 170L cylinder, but I am concerned we may run out of hot water.
Will 170L suffice? Is 210L excessive?
There is the space for 210, however it's a small flat which lacks cupboards, and we were hoping to use the extra cupboard space for towel shelves. I am also aware of the money saved on a smaller cylinder and lower annual heating costs.
In terms of the model, my preferrred plumber is recommending a MAIN cylinder (25 year warranty 1 year on parts), but I can find no reviews about this make at all. This makes me wary. I've seen MAIN mentioned once or twice here, just to say they are "ok".
Main Unvented Cylinders - https://www.mainheating.co.uk/main-products/unvented-cylinders/main-unvented-cylinders
The EvoCyl Air has also been quoted for by another plumber (25 year warranty 2 years on parts):
Evocyl Air Standard | ThermaQ - http://www.thermaq.co.uk/products-2/evocyl-air-standard/
Again I can find no reviews, though it's brochure and shpiel are impressive. Is anyone here familiar with either of these?
My third quote was for a Mega-Flo, as I understand it this is the industry standard, (lifetime warranty, 5 year warranty on expansion vessel and 2 years on other parts) and is considered very good, although much more expensive than perhaps equally good competitors.
Apart from the warranty, I do not really see the benefits of it. I am not even sure if an internal expansion vessel is even preferrable.
Am I right in thinking all mid range to top end cylinders do pretty much the same thing? None produce greater flow or pressure, all heat in a similar amount time? All similar quality steel cylinders. Is that right?
In which case which cylinder to choose?
I see on this forum Joule and Gledhill get mentioned favourably.
A couple of further questions:
1) Will using the kitchen tap/dishwasher effect my shower flow/pressure? IF so can I do anything be done about this?
2) We live in London, a hard water area, do I need to do anything about this? My plumber has suggested a limescale inhibitor, and advised against a water softener, in part due to space issues.
------
Once the UC is in we will need to completely redo the bathroom. New sink, bath, Mira Excel shower, electric towel rail, humidistat extractor fan, drop ceiling, ceiling lights, wall tiles and floor tiles.
3) I presume it is best to do the boiler first, and wait and see how pipes react to mains pressure, then do the bathroom. Is that right?
4) What are the annual costs for servicing an unvented cylinder?
Ok, that's about it!
Any advice on the above would be greatly appreciated. Thank you for your time.
[automerge]1600357386[/automerge]
Found this rather excellent response on another thread:
[IMG alt="mubesjnr"]https://plumbers.s3.eu-west-1.amazonaws.com/data/avatars/m/26/26543.jpg?1547491930[/IMG]
mubesjnr
Mar 7, 2019
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.
[automerge]1600357974[/automerge]
Here is a list of recommended cylinders I have seen online:
Best Unvented Cylinders 2020 | Review Brands, Price & Performance - https://www.boilerguide.co.uk/articles/best-unvented-cylinders
We are having an Unvented Cylinder installed into our 2 bedroom ground floor flat. I have had a few quotes and been given lots of differing advice, this always makes me wary, especially having suffered a history of poor quality work by cowboys in the past. Which is why I am here.
The question is in the title: What make of Direct Unvented Cylinder, and what size?
I am going to include all the information so that this thread can be of use to others with the same question.
I have had 3 quotes and 3 different cylinders suggested: Mega-Flo, evoCyl and Main. Everyone knows Mega, the other 2 are a mystery to me.
The specifics:
This is a two bed, one bathroom flat with a P shaped shower bath (similar to the one in the image below), so the bath takes a little more water than average to fill.
We currently have an ageing electric shower and a failing immersion heater and tank. Just barely 20L pm , and just barely 2 bar. Appalling pressure and flow from the current gravity system (ground floor). The flats are all electric, no gas. Almost all the plumbers agree that UC is the answer.
The boiler cupboard is right by the bathroom, as well as by the block of flats mains stopcocks, these have blue pipe, so I presume 25mm.
We are a couple with a 5 year old boy. So we tend to have on average 3 showers a day, although we can easily have a shower, a childs bath and an adult bath in one day. As my wife and I both like baths, sometimes (but not regularly) 2 baths in a day.
There is also a dishwasher and washing machine (I presume these only take cold from the mains).
We have E7 heating.
The electric shower will be replaced by a Mira Excel thermostatic shower, we are also getting a thermostatic bumgun.
Most plumbers have recommended 150 or 170L cylinder, but I am concerned we may run out of hot water.
Will 170L suffice? Is 210L excessive?
There is the space for 210, however it's a small flat which lacks cupboards, and we were hoping to use the extra cupboard space for towel shelves. I am also aware of the money saved on a smaller cylinder and lower annual heating costs.
In terms of the model, my preferrred plumber is recommending a MAIN cylinder (25 year warranty 1 year on parts), but I can find no reviews about this make at all. This makes me wary. I've seen MAIN mentioned once or twice here, just to say they are "ok".
Main Unvented Cylinders - https://www.mainheating.co.uk/main-products/unvented-cylinders/main-unvented-cylinders
The EvoCyl Air has also been quoted for by another plumber (25 year warranty 2 years on parts):
Evocyl Air Standard | ThermaQ - http://www.thermaq.co.uk/products-2/evocyl-air-standard/
Again I can find no reviews, though it's brochure and shpiel are impressive. Is anyone here familiar with either of these?
My third quote was for a Mega-Flo, as I understand it this is the industry standard, (lifetime warranty, 5 year warranty on expansion vessel and 2 years on other parts) and is considered very good, although much more expensive than perhaps equally good competitors.
Apart from the warranty, I do not really see the benefits of it. I am not even sure if an internal expansion vessel is even preferrable.
Am I right in thinking all mid range to top end cylinders do pretty much the same thing? None produce greater flow or pressure, all heat in a similar amount time? All similar quality steel cylinders. Is that right?
In which case which cylinder to choose?
I see on this forum Joule and Gledhill get mentioned favourably.
A couple of further questions:
1) Will using the kitchen tap/dishwasher effect my shower flow/pressure? IF so can I do anything be done about this?
2) We live in London, a hard water area, do I need to do anything about this? My plumber has suggested a limescale inhibitor, and advised against a water softener, in part due to space issues.
------
Once the UC is in we will need to completely redo the bathroom. New sink, bath, Mira Excel shower, electric towel rail, humidistat extractor fan, drop ceiling, ceiling lights, wall tiles and floor tiles.
3) I presume it is best to do the boiler first, and wait and see how pipes react to mains pressure, then do the bathroom. Is that right?
4) What are the annual costs for servicing an unvented cylinder?
Ok, that's about it!
Any advice on the above would be greatly appreciated. Thank you for your time.
[automerge]1600357386[/automerge]
Found this rather excellent response on another thread:
[IMG alt="mubesjnr"]https://plumbers.s3.eu-west-1.amazonaws.com/data/avatars/m/26/26543.jpg?1547491930[/IMG]
mubesjnr
Mar 7, 2019
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.
[automerge]1600357974[/automerge]
Here is a list of recommended cylinders I have seen online:
Best Unvented Cylinders 2020 | Review Brands, Price & Performance - https://www.boilerguide.co.uk/articles/best-unvented-cylinders
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