Evening all, I'm after some advice/guidance.
I'm refurbing my 2 bed bungalow and will be extending it in the near future. I need to replace my heating system but I'd like to understand my options and requirements before I engage with an engineer. I've tried to do some research but I'm relatively new to this area so if I've misunderstood anything, please correct me!
The renovation & extension will see up to 9 additional radiators, a second bathroom/shower and a utility room with a shower specifically for the pooch.
One engineer suggested a 30kW combi based on my plans for the extension, but I've since read that even a high powered combi may not be able to cope with multiple showers; and whilst I live alone and its unlikely more than one tap or shower will be running simultaneously, I don't want to have to replace the boiler prematurely should the demand increase!
I'm therefore considering a system boiler with unvented hot water storage. Alternatively, a combi for now, which I've read can be 'converted' to use an unvented cylinder in the future. Used in this way, would a combi boiler still be efficient?
Either way, how do I ensure the boiler isn't oversized? I've calculated the future heating requirement at 13.6kW (although it's an older 60s property so it could be a little more.) I'd prefer to have a lower flow/return rate (to ensure the boiler actually condenses) so I plan to oversize the radiators to compensate (adjusted for Δt40).
This may seem a stupid question, but should the boiler meet the heating requirement for the house (13.6kW) or does it need to meet the total output for the oversized rads (18.2kW)? What about the cylinder? Should this be included in the kW output? How do I calculate this?
Thanks for any advice - like I said, I will be speaking to an engineer - I just want to make sure I have enough knowledge so I don't get sold something that isn't suitable or oversized.
Art
I'm refurbing my 2 bed bungalow and will be extending it in the near future. I need to replace my heating system but I'd like to understand my options and requirements before I engage with an engineer. I've tried to do some research but I'm relatively new to this area so if I've misunderstood anything, please correct me!
The renovation & extension will see up to 9 additional radiators, a second bathroom/shower and a utility room with a shower specifically for the pooch.
One engineer suggested a 30kW combi based on my plans for the extension, but I've since read that even a high powered combi may not be able to cope with multiple showers; and whilst I live alone and its unlikely more than one tap or shower will be running simultaneously, I don't want to have to replace the boiler prematurely should the demand increase!
I'm therefore considering a system boiler with unvented hot water storage. Alternatively, a combi for now, which I've read can be 'converted' to use an unvented cylinder in the future. Used in this way, would a combi boiler still be efficient?
Either way, how do I ensure the boiler isn't oversized? I've calculated the future heating requirement at 13.6kW (although it's an older 60s property so it could be a little more.) I'd prefer to have a lower flow/return rate (to ensure the boiler actually condenses) so I plan to oversize the radiators to compensate (adjusted for Δt40).
This may seem a stupid question, but should the boiler meet the heating requirement for the house (13.6kW) or does it need to meet the total output for the oversized rads (18.2kW)? What about the cylinder? Should this be included in the kW output? How do I calculate this?
Thanks for any advice - like I said, I will be speaking to an engineer - I just want to make sure I have enough knowledge so I don't get sold something that isn't suitable or oversized.
Art