Hello
I live in a 3 bed/1 bathroom mansionette and I've always had a conventional boiler, so when the boiler is working ok it's something I'm happy with and I don't give it a second thought. After on going issues with my current boiler (Baxi Solo 3 PFL 50), the time has come for a replacement, however, Smith & Byford want to rip out my conventional system and replace with a combi. When I was told this I advised I'd much rather stick with conventional. Reply was that they will add a note to the quote given to the council saying I'd prefer conventional replacement, but as it will be cheaper to install combi they can't see council opting for anything else.
Given the fact that to install a combi would need a lot of extra pipe work in kitchen, extra new mains pipes runs upstairs and removal of HW tank and cold water storage tank, I cannot see how installing a combi would be the cheaper option over simply removing old conventional boiler and replacing with new. That just seem logical to me, but I'm no expect in these matters so it would be good to hear your thoughts on this please?
As I'm 'just' a tenant I don't have much say in the matter at the end of the day, as was so clearly illustrated to me by surveyor who advise council will simply say 'you're get what you are given', however, if my logic is correct that like for like replacement should actually be cheaper (or at worst same price) than converting to combi, then I'll have a good reason to backup my argument.
Until my recent boiler problems, I knew next to nothing about combi. The only think I knew of combi was that they produce 'instant' hot water. I'm perfectly happy with my hot water which is pretty much already instant, so this benefit is lost on me. Another main benefit appear to be that you can get rid of tanks, but I already have enough space that only fills with junk. Thought I'd do some research re conventional vs combi and opinions still seem largely divided, and very much depends on user demands.
From extensive reading various forums and guides, I think I've pretty much got to the bottom of the pros and cons of the two systems now, and I'm sure the conventional will still suit me much better, but would still like others opinions in case I've missed something. I've included some facts and questions below so you can tell me what you think is best suited for my situation... conventional or combi?
I got surveyor to measure mains. He used just the kitchen tap (no others were running). His meter reader maxed out at 22 liter, so couldn't gather an accurate reading other than it was over 22 litres.
Mains litres per minute: 22+ litres
Mains Pressure measured: 3.8 bar
Current Boiler: Baxi Solo 3 PFL 50 (around 15 years old)
Proposed combi: Valliant ecotec Pro 28
Proposed conventional: Valliant 615 or 618 (IF council would agree to conventional)
1. I use very little hot water. I heat up just enough to cover for what I use. The boiler is on 30 mins in the morning and 30 mins in afternoon ready for a bath after work. Other than that it's on for heating 1-2 hours some nights. Gas usage averages around £30 a month which I think this is pretty good. Combi are said to reduce bills, but is this likely considering my limited use already?
2. I mainly bath and understand that it will take considerable longer to run a bath with a combi. Takes about 5 mins at present. Taking in to account my mains pressure/flow rate (3.8 bar / 22), any ideas how much longer it would take? Boiler they propose to install would be Valliant ecotec pro 28 which has 11.1 flow rate.
3. Some years back I saved and got a power shower (Mira Excel) installed. 2 bar pump and shower is fantastic, very powerful to the point you get that tingling feeling from water hitting the skin (on particular head settings). Some people have said it's a little TOO powerful as they feel like they have just been beaten up by it! Of course I can kiss good bye to the pump if combi is forced on me. Using pretty basic method of bucket and measuring jug I measured 11.5 litres per minute for current setup. This was surprising as thought it would be more. Taking into account mains pressure/flow rate (3.8 bar / 22) and combi boiler output (11.1), would I noticed a considerable difference? Would shower still be half decent at least?
4. If I have no choose but to accept the combi, I'd consider asking if I can pay the extra for next models up (maybe Plus 832 with 13 litre per min) for increased flow rate for better shower and faster filling baths. However, I've read that while a more powerful combi will help achieve this, the output for the heating would then be overkill and therefore it won't run as efficiently. True? Would 13 l/m vs 11.1 l/m give noticeable different that you can feel in shower?
5. I haven't done much reading up on conventional boilers, but IF council would agree to go with another of these, is the Valliant 615 or 618 a good choice, or should I look toward next models up? I understand bigger combi's equals better flow rate, but as flow rate wouldn't be issue with new conventional, not sure of any benefits of bigger/more power conventional? Considering current boiler has output of 18.3kW, Vallient 615 has 15.9kW and 618 has 19.1kW makes sense to opt for 618 as this is closest to my current boiler's output (which I'm happy with... when it works). Make sense or would 615 be ok? What difference if any would I notice with lower output of the 615?
6. Surveyor said they would only do a chemical flush (not power flush). All rads have typical 'mountain' shape area at bottom of rads which I understand is a clear indication of sludge. Is chemical flush acceptable in such instance?
Thanks for reading, and sorry it's so long. I just want to make sure I don't end up disappointed. Might not have much say in the matter really, but have a better chance if I can put forward a well informed argument.
Thank you
I live in a 3 bed/1 bathroom mansionette and I've always had a conventional boiler, so when the boiler is working ok it's something I'm happy with and I don't give it a second thought. After on going issues with my current boiler (Baxi Solo 3 PFL 50), the time has come for a replacement, however, Smith & Byford want to rip out my conventional system and replace with a combi. When I was told this I advised I'd much rather stick with conventional. Reply was that they will add a note to the quote given to the council saying I'd prefer conventional replacement, but as it will be cheaper to install combi they can't see council opting for anything else.
Given the fact that to install a combi would need a lot of extra pipe work in kitchen, extra new mains pipes runs upstairs and removal of HW tank and cold water storage tank, I cannot see how installing a combi would be the cheaper option over simply removing old conventional boiler and replacing with new. That just seem logical to me, but I'm no expect in these matters so it would be good to hear your thoughts on this please?
As I'm 'just' a tenant I don't have much say in the matter at the end of the day, as was so clearly illustrated to me by surveyor who advise council will simply say 'you're get what you are given', however, if my logic is correct that like for like replacement should actually be cheaper (or at worst same price) than converting to combi, then I'll have a good reason to backup my argument.
Until my recent boiler problems, I knew next to nothing about combi. The only think I knew of combi was that they produce 'instant' hot water. I'm perfectly happy with my hot water which is pretty much already instant, so this benefit is lost on me. Another main benefit appear to be that you can get rid of tanks, but I already have enough space that only fills with junk. Thought I'd do some research re conventional vs combi and opinions still seem largely divided, and very much depends on user demands.
From extensive reading various forums and guides, I think I've pretty much got to the bottom of the pros and cons of the two systems now, and I'm sure the conventional will still suit me much better, but would still like others opinions in case I've missed something. I've included some facts and questions below so you can tell me what you think is best suited for my situation... conventional or combi?
I got surveyor to measure mains. He used just the kitchen tap (no others were running). His meter reader maxed out at 22 liter, so couldn't gather an accurate reading other than it was over 22 litres.
Mains litres per minute: 22+ litres
Mains Pressure measured: 3.8 bar
Current Boiler: Baxi Solo 3 PFL 50 (around 15 years old)
Proposed combi: Valliant ecotec Pro 28
Proposed conventional: Valliant 615 or 618 (IF council would agree to conventional)
1. I use very little hot water. I heat up just enough to cover for what I use. The boiler is on 30 mins in the morning and 30 mins in afternoon ready for a bath after work. Other than that it's on for heating 1-2 hours some nights. Gas usage averages around £30 a month which I think this is pretty good. Combi are said to reduce bills, but is this likely considering my limited use already?
2. I mainly bath and understand that it will take considerable longer to run a bath with a combi. Takes about 5 mins at present. Taking in to account my mains pressure/flow rate (3.8 bar / 22), any ideas how much longer it would take? Boiler they propose to install would be Valliant ecotec pro 28 which has 11.1 flow rate.
3. Some years back I saved and got a power shower (Mira Excel) installed. 2 bar pump and shower is fantastic, very powerful to the point you get that tingling feeling from water hitting the skin (on particular head settings). Some people have said it's a little TOO powerful as they feel like they have just been beaten up by it! Of course I can kiss good bye to the pump if combi is forced on me. Using pretty basic method of bucket and measuring jug I measured 11.5 litres per minute for current setup. This was surprising as thought it would be more. Taking into account mains pressure/flow rate (3.8 bar / 22) and combi boiler output (11.1), would I noticed a considerable difference? Would shower still be half decent at least?
4. If I have no choose but to accept the combi, I'd consider asking if I can pay the extra for next models up (maybe Plus 832 with 13 litre per min) for increased flow rate for better shower and faster filling baths. However, I've read that while a more powerful combi will help achieve this, the output for the heating would then be overkill and therefore it won't run as efficiently. True? Would 13 l/m vs 11.1 l/m give noticeable different that you can feel in shower?
5. I haven't done much reading up on conventional boilers, but IF council would agree to go with another of these, is the Valliant 615 or 618 a good choice, or should I look toward next models up? I understand bigger combi's equals better flow rate, but as flow rate wouldn't be issue with new conventional, not sure of any benefits of bigger/more power conventional? Considering current boiler has output of 18.3kW, Vallient 615 has 15.9kW and 618 has 19.1kW makes sense to opt for 618 as this is closest to my current boiler's output (which I'm happy with... when it works). Make sense or would 615 be ok? What difference if any would I notice with lower output of the 615?
6. Surveyor said they would only do a chemical flush (not power flush). All rads have typical 'mountain' shape area at bottom of rads which I understand is a clear indication of sludge. Is chemical flush acceptable in such instance?
Thanks for reading, and sorry it's so long. I just want to make sure I don't end up disappointed. Might not have much say in the matter really, but have a better chance if I can put forward a well informed argument.
Thank you
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