Changing an oil fire boiler
Discussion
Our oil fired boiler is now 20 years old and starting to show its age. Despite regular servicing it trips out fairly regularly.
As such, I'm thinking that it might be time to bite the bullet and replace it. Presently we have a conventional system - hot water cylinder in airing cupboard, cold water tank in loft. Again, fairly typically, we have a pump fitted to improve water pressure, particularly to the showers. Serves a reasonable size four bed house.
I'm trying to decide on a number of things:
a) should we move to a boiler mounted in a cabinet on the exterior of the house, to free up wall space when we do over the kitchen
b) is there significant additional value in switching to a combi.
In terms of the former, it'd be nice, but not essential.
The latter interests me, as it opens up the later option of a loft conversion, but we don't really need the space anytime soon. I'm more interested in whether we'd notice performance gains from swapping to an oil combi.
If we were on gas, the decision is easy. I'm new to oil though, so interested in thoughts.
As such, I'm thinking that it might be time to bite the bullet and replace it. Presently we have a conventional system - hot water cylinder in airing cupboard, cold water tank in loft. Again, fairly typically, we have a pump fitted to improve water pressure, particularly to the showers. Serves a reasonable size four bed house.
I'm trying to decide on a number of things:
a) should we move to a boiler mounted in a cabinet on the exterior of the house, to free up wall space when we do over the kitchen
b) is there significant additional value in switching to a combi.
In terms of the former, it'd be nice, but not essential.
The latter interests me, as it opens up the later option of a loft conversion, but we don't really need the space anytime soon. I'm more interested in whether we'd notice performance gains from swapping to an oil combi.
If we were on gas, the decision is easy. I'm new to oil though, so interested in thoughts.
We`ve got a Grant condensing oil boiler mounted outside, it certainly cuts down the noise and smell. Its moderately insulated, but because of the air intake, it cant really be fully covered in insulation, so when it gets really cold the frost prevention kicks in and it fires up. Probably the main downside.
Oh, its a conventional boiler, much prefer these to combis..
Oh, its a conventional boiler, much prefer these to combis..
Edited by .:ian:. on Friday 21st October 15:25
I think oil fired combis are flawed, certainly my experience. Gas combis on the other hand seem to be great as long as you have sufficient pressure / flow.
After a lot of research we went for a Grant oil boiler in the garage with an unvented 250l tank also in the garage. We have 7 Bar and about 30 l/min coming into the house, reduced to 3 bar will still power two showers simultaneously upstairs well.
After a lot of research we went for a Grant oil boiler in the garage with an unvented 250l tank also in the garage. We have 7 Bar and about 30 l/min coming into the house, reduced to 3 bar will still power two showers simultaneously upstairs well.
FWIW this guy is a PHer and runs his own oil-fired boiler company: https://www.facebook.com/HounsfieldBoilersLtd/
Venom said:
Our oil fired boiler is now 20 years old and starting to show its age. Despite regular servicing it trips out fairly regularly.
As such, I'm thinking that it might be time to bite the bullet and replace it. Presently we have a conventional system - hot water cylinder in airing cupboard, cold water tank in loft. Again, fairly typically, we have a pump fitted to improve water pressure, particularly to the showers. Serves a reasonable size four bed house.
I'm trying to decide on a number of things:
a) should we move to a boiler mounted in a cabinet on the exterior of the house, to free up wall space when we do over the kitchen
b) is there significant additional value in switching to a combi.
We have an oil boiler approaching 20yrs old. It's a Worcester Bosch system boiler floor standing & 'kitchen' model which means it has a bit more sound insulation than a 'utility room' model. It lives inside a cupboard in our utility room (which abuts the kitchen) and although it's always been pretty quiet I'm glad it's not located in the kitchen. Not sure any oil boiler will ever be a quiet as a comparable output gas boiler. It has a very, very faint whiff of oil when operating (even when brand new) though most people wouldn't recognise the smell. However when it is serviced there is an overpowering but short term stench of kerosene/home heating oil when the plumber changes a few service items. Wouldn't want that smell in a kitchen even just for a couple of hours!As such, I'm thinking that it might be time to bite the bullet and replace it. Presently we have a conventional system - hot water cylinder in airing cupboard, cold water tank in loft. Again, fairly typically, we have a pump fitted to improve water pressure, particularly to the showers. Serves a reasonable size four bed house.
I'm trying to decide on a number of things:
a) should we move to a boiler mounted in a cabinet on the exterior of the house, to free up wall space when we do over the kitchen
b) is there significant additional value in switching to a combi.
Traditionally, combis were specced for flats/small houses where HW demand was lower at peak times than larger properties. Combi technology may have moved on though.
Our oil boiler is 30 years old. It's looked after by a damn good local guy. All the parts are available apart from the 'block' when that goes, it's a new one. He said there's no point replacing it at the moment. If yours keeps tripping out, then I'd be looking at getting a decent service engineer who can look after it properly rather than making it look bad so you spend lots of money with him to replace it.
We had a really old Worcester Bosch oil combi in the kitchen when we moved in, it was really noisy, big and smelly, but did have great hot water flow rate and worked well.
We then started the process of installing a new kitchen and to make the units work how we wanted we had to change to a conventional boiler and put in an unvented cylinder. This also gave us a backup of having the immersion heater in the cylinder just incase we either run out of oil, the oil gets pinched or the boiler breaks.
The new boiler is another Worcester Bosch and is built into a cupboard in the kitchen, the noise certainly isn't intrusive and we don't get any oil odour anymore.
One reason oil boilers smell is careless engineers who drop oil on the floor, don't clean it up and it soaks into the concrete. To prevent this prior to installing it I sealed all of the concrete under the boiler and around it so if there is a small spill when servicing it can be easily cleaned up.
We then started the process of installing a new kitchen and to make the units work how we wanted we had to change to a conventional boiler and put in an unvented cylinder. This also gave us a backup of having the immersion heater in the cylinder just incase we either run out of oil, the oil gets pinched or the boiler breaks.
The new boiler is another Worcester Bosch and is built into a cupboard in the kitchen, the noise certainly isn't intrusive and we don't get any oil odour anymore.
One reason oil boilers smell is careless engineers who drop oil on the floor, don't clean it up and it soaks into the concrete. To prevent this prior to installing it I sealed all of the concrete under the boiler and around it so if there is a small spill when servicing it can be easily cleaned up.
V8RX7 said:
jmsgld said:
unvented 250l tank also in the garage. We have 7 Bar and about 30 l/min coming into the house, reduced to 3 bar will still power two showers simultaneously upstairs well.
To be clear you are running your house on 3 Bar, 7 is just the incoming mains pressure ?I think the tank is only rated to 3 Bar, so to keep it balanced the cold is also reduced to 3 Bar.
Oil combis are evil - I don't know anyone who has one in a house, but a few of our work buildings have them. Terrible things.
OP - have you considered just replacing the burner? Typically around £130 for a Riello (market leaders), and one or two bolts hold it on. It'd take you an hour, max to do it.
OP - have you considered just replacing the burner? Typically around £130 for a Riello (market leaders), and one or two bolts hold it on. It'd take you an hour, max to do it.
Our oil combi boiler was a `Warmflo` which was sited outside in an insulated box. Most of the internals seemd to be Riello. Worked well, but even better when the internal expansion vessel was replaced with a much larger one housed inside the adjacent wall. We did worry about arriving home to find it had all disappeared on the back of a transit pickup (only 3 or 4 pipes to cut through) but it stayed happily in place.
When I absolutely HAVE to spec an oil combi, I always spec Kabin Paks by Warmflow. Sits outside in it's own little box, no big flue needed, expansion vessel and all in the cabinet, and a good Riello burner.
They are the only ones I have ever had any real success with, but according to our contractors they are a ball-ache to work on if they do go wrong.
That could be because they are pretty rare, though.
http://www.warmflow.co.uk/products/boilers/k-serie...
They are the only ones I have ever had any real success with, but according to our contractors they are a ball-ache to work on if they do go wrong.
That could be because they are pretty rare, though.
http://www.warmflow.co.uk/products/boilers/k-serie...
LambShank said:
I had a new floor standing oil combi installed in the utility room a year ago.
Absolutely nothing wrong with it whatsoever.
Great flow, lovely hot shower and no oil smells at all.
I reckon those with issues have obviously had a crap installation.
Agreed, oil combis typically outperform their gas counterparts in the hot water flow department.Absolutely nothing wrong with it whatsoever.
Great flow, lovely hot shower and no oil smells at all.
I reckon those with issues have obviously had a crap installation.
They have a slow heat up time compared to gas boiler, so wouldn't be able to produce hot water instantaneously like a gas model. So they use a thermal store to keep a small quantity (I'd guess 50L) of water at high temperature, ready to pump round the plate heat exchanger to create domestic hot water, this gives the burner and the main heat exchanger time to play catch up.
An oil fired Worcester Heatslave 25/32 will produce hot water at 22L/min compared to the gas fired CDI Classic 42kw at 17L/min.
That said, combis are a compromise! I'd have a conventional boiler with an unvented cylinder everytime if money and space wasn't an issue.
Rickyy said:
oil combis have a slow heat up time compared to gas boiler, so wouldn't be able to produce hot water instantaneously like a gas model. So they use a thermal store to keep a small quantity (I'd guess 50L) of water at high temperature
^^^ Lambshank - that's why everyone says they aren't great because the entire point of a combi was near instantaneous hot water without having to store it.If you're going to store it you may as well do so in a larger tank and have a considerably cheaper boiler.
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