my_name_is_slim_daisy
Member
- Messages
- 42
- Location
- London
Good question! Why am I doing this…. A few of the radiators are sludgy (2-3).
When I had my new combi boiler installed last year, the gas engineer did a flush of the system, although I don’t think this was a long-running flush. Should I consider doing a longer flush first before replacing? I worry slightly that it’ll be pointless and I’ve forked out a few hundred bob (probably more with London plumber prices), which could have gone towards the replacement radiators.
Then one radiator is too small for the room it’s in. I sourced the radiators based on the BTUs calculated by one of the cast iron radiator companies (the few days I was on cloud nine dreaming too big, after being inspired by the fine houses in Bridgerton). Coincidentally most of the prospective radiators ended up being similar dimensions to the existing ones. The hallway radiator could actually be smaller based on the BTU I was given, but I do like the hallway warm and therefore opted for the same size. Happy to rethink this as it would give me a bit more room to get a small wardrobe in the hallway for hanging coats and storing shoesies.
In terms of positioning of radiators, I’m quite happy with where they are already - mainly below the windows in each room (which are single glazed in most places). After reading the scientific explanations in this thread
, I think I’ll leave them under the windows! The dining room one I’m tempted to move to the wall adjacent to the hallway, but this would mean installing the radiator onto the wall holding the fusebox and electric meter on the other side, and it would then also be roughly 1 metre away from the hallway radiator - I don’t know if this is an efficient layout? The other reason to move it is, in the future (could be 2 years, could be 5 years, could be 50) I’m planning a side return, and the dining room wall where the existing radiator sits, will probably have french doors opening into the kitchen.
Now one of the other reasons I’m doing a blanket replacement of ALL radiators is because of a micro leak (and also because the existing pipe work is very exposed and hideous). After the new boiler was installed, the boiler pressure dropped from ~1.5 to 0.9 in the space of around 3 weeks (the engineer explained it as the system still settling down, and we do know there was some air in the system). He was quite an unpleasant person after getting his money and was extremely defensive/difficult about his work and my questions, so I contacted Vaillant. They suspected a micro leak somewhere in the system, but said it’s hard to pinpoint because it’s so small it will probably evaporate before finding it. They topped up the pressure to ~1.4, and 3 weeks after their visit it dropped to 1.3. Over the next 3 months it dipped to around 1.1. I last topped up the boiler in Aug 2025 to 1.6 and it’s currently around 1.5. Long story short, I’m hoping by replacing some of the radiators and pipework, we may find/fix the leak. I know I should lift up the floorboards and try to find the leak myself, but with it being the first house, everything feels like “101”…. my head is exploding with bits and bobs of DIY, and it doesn’t help that when I attempt some DIY (wallpaper, painting) I do a horrendous job, causing more work (sorry about the rant).
I hadn’t thought about the disposal of radiators, I’d better clear that up with the plumbers. It’s not an option for me to dispose of them! I already have a garden shed full of insulation and rubble that’s been sitting there for a year, and my lovely garden already looks like a scrapyard, just without a Rottweiler! @a twig , good suggestion, but the neighbours will have my guts for garters.
So my revised plan now is to just replace the sludgy radiators and small radiator for now and leave the rest as they are (after winter of course, unless I find a good plumber before winter kicks in). Also gives me time to pick shrouds/collars to hopefully neaten up the pipe work and floor area.
When I had my new combi boiler installed last year, the gas engineer did a flush of the system, although I don’t think this was a long-running flush. Should I consider doing a longer flush first before replacing? I worry slightly that it’ll be pointless and I’ve forked out a few hundred bob (probably more with London plumber prices), which could have gone towards the replacement radiators.
Then one radiator is too small for the room it’s in. I sourced the radiators based on the BTUs calculated by one of the cast iron radiator companies (the few days I was on cloud nine dreaming too big, after being inspired by the fine houses in Bridgerton). Coincidentally most of the prospective radiators ended up being similar dimensions to the existing ones. The hallway radiator could actually be smaller based on the BTU I was given, but I do like the hallway warm and therefore opted for the same size. Happy to rethink this as it would give me a bit more room to get a small wardrobe in the hallway for hanging coats and storing shoesies.
In terms of positioning of radiators, I’m quite happy with where they are already - mainly below the windows in each room (which are single glazed in most places). After reading the scientific explanations in this thread
, I think I’ll leave them under the windows! The dining room one I’m tempted to move to the wall adjacent to the hallway, but this would mean installing the radiator onto the wall holding the fusebox and electric meter on the other side, and it would then also be roughly 1 metre away from the hallway radiator - I don’t know if this is an efficient layout? The other reason to move it is, in the future (could be 2 years, could be 5 years, could be 50) I’m planning a side return, and the dining room wall where the existing radiator sits, will probably have french doors opening into the kitchen.Now one of the other reasons I’m doing a blanket replacement of ALL radiators is because of a micro leak (and also because the existing pipe work is very exposed and hideous). After the new boiler was installed, the boiler pressure dropped from ~1.5 to 0.9 in the space of around 3 weeks (the engineer explained it as the system still settling down, and we do know there was some air in the system). He was quite an unpleasant person after getting his money and was extremely defensive/difficult about his work and my questions, so I contacted Vaillant. They suspected a micro leak somewhere in the system, but said it’s hard to pinpoint because it’s so small it will probably evaporate before finding it. They topped up the pressure to ~1.4, and 3 weeks after their visit it dropped to 1.3. Over the next 3 months it dipped to around 1.1. I last topped up the boiler in Aug 2025 to 1.6 and it’s currently around 1.5. Long story short, I’m hoping by replacing some of the radiators and pipework, we may find/fix the leak. I know I should lift up the floorboards and try to find the leak myself, but with it being the first house, everything feels like “101”…. my head is exploding with bits and bobs of DIY, and it doesn’t help that when I attempt some DIY (wallpaper, painting) I do a horrendous job, causing more work (sorry about the rant).
I hadn’t thought about the disposal of radiators, I’d better clear that up with the plumbers. It’s not an option for me to dispose of them! I already have a garden shed full of insulation and rubble that’s been sitting there for a year, and my lovely garden already looks like a scrapyard, just without a Rottweiler! @a twig , good suggestion, but the neighbours will have my guts for garters.
So my revised plan now is to just replace the sludgy radiators and small radiator for now and leave the rest as they are (after winter of course, unless I find a good plumber before winter kicks in). Also gives me time to pick shrouds/collars to hopefully neaten up the pipe work and floor area.
, I'm just surprised people ignore the window rule, its always seemed quite prevalent.
