Oil Central Heating to Gas Combi Boiler Install

[Darkitect]

Hello. Thank you in advance for any advice. It is much appreciated. I am interested in converting our home from oil central heating to a gas combi-boiler. Background/Existing house system: We had a gas supplier promotion slipped through our letterbox saying that gas is available on our street and we could contact them if we were interested in converting to it. Our townhouse is currently fed via a large oil tank that is located in our back yard. The oil tank connects to an internal room on the ground floor where an oil boiler is located. It has a flue through the roof. The system has an insulated tank on the first floor. The system also has a water storage tank in roof space (above second floor). We have two showers. The shower on the second floor is an Aqualisa Aquastream pressure shower unit. I assume to increase water pressure. The shower on the first floor is an electric pressure & heating shower (it backs onto insulated tank/drying cupboard). Elsewhere, there are 7 handbasins, 3 toilets, 1 sink, 1 dishwasher & 1 washing machine.

From my research I understand the following:

1) The combi-boiler may cause water supply issues if more than one fixture is used at the same time. I have a 4 person family, so is this a big issue? Is there any way around this?
2) The electric showers may need to be replaced with normal shower taps/rose. I'm ok with this but there is an additional cost I need to allow for for replumbing & plumbing fixtures.
3) The roof tank will no longer be needed as the combi-boiler will suppy a water pressure comparable to that from the street. Will this pressure be enough to go up 2 storeys?
4) The insulated storage tank will not be required as hot water is delivered direct from Combi-boiler.

If there is any concerns I should have for this, I would love to hear them. And if anyone give me a rough idea of overall cost for install in Northern Ireland.

Thanks in advance.

 

[ShaunCorbs]

I would ask and see how much it would cost to get mains gas in

 

[king of pipes]

A combi boiler is not the way to go by all means get some estimates to get you connected to the gas network but don't be talked into a quick fix combi .Cheers Kop

 

[gmartine]

Again, a combi is not necessarily a panacea to your HW supply issues and besides the cost of heating oil isn't too bad atm and a maintained oil boiler is generally reliable. Unless you really need the space why are you thinking of changing?

 

[Darkitect]

No, we don’t need the space. The house is huge. The reasons are:

1) The convenience of reticulated gas vs having to get the oil tank refilled all year.
2) The removal of the roof space water tank, which currently sits on a party wall. We will then be able to install fire walls in the roof space to separate the roof space from the neighbours.
3)The removal of power showers will simplify the system. We will
also not have to pay for the power shower wall switch to be relocated as it currently sits too close to the recently installed bath.
4)All rooms have basins (it’s an old house) and mains feed hot and cold water supply is more potable than the water from the roof tank.
5) Oil boiler in room and oil tank out back smells of oil. Tank out back is nasty looking and sits prominently in back garden.

Thanks again.

 

[Harvest Fields]

If your house is a 4 bedroom or bigger a Combi is not recommended.

 

[Darkitect]

If your house is a 4 bedroom or bigger a Combi is not recommended.

Thanks for the advice. Is there a reason why this is? And is there an alternative gas boiler that can be used instead of a combi-boiler? Cheers.

 

[Harvest Fields]

Thanks for the advice. Is there a reason why this is? And is there an alternative gas boiler that can be used instead of a combi-boiler? Cheers.

Hot water demand and yes. It will be almost what you have now but for gas.

 

[Best]

A quality install of a good oil boiler (I prefer Grant Vortex oil boiler) with full controls would be very comparable to a gas boiler, in efficiency, running costs and performance.
You could go with an unvented cylinder if pressure and flow rates of your mains supply is ok, using a gas or oil boiler.
That would allow you to have high pressure and good flow at every shower valve and tap. Still could also have electric (heating element) showers, but not any pumped showers, or separate pumps.
A new bunded oil tank can be very neat.
You shouldn’t really have smell of oil at a bunded tank and definitely no smell around a modern oil boiler