Gas or Oil

turboace

My property is heated by a 20 year old oil boiler.  It runs ok but engineers say its about 30% inefficient. 

The property is a 1970s bungalow with a well insulated loft, cavity wall insulation, and double glazing. 

Quotes suggest costs to upgrade the heating system are £8k for oil and ££6.5k for gas, including connection.  My calculations suggest annual heating by oil would be about £350 cheaper or £550 with the predicted 20% increase.

What to do? 

BUFF

is there mains gas already supplied to the house or at least in the street nearby?
are you including the cost of maintaining/replacing over time the oil tank?
It is only relatively recently afaik that oil has become cheaper to run than gas & who knows what may happen to prices in the future ...

 

lohr500

Hi turboace.

Firstly I would say that £8k sounds very expensive to replace an existing oil boiler with a new one. Does the quote include relocating the boler or changing it to a different type with associated plumbing changes? (eg regular boiler to combi).

We paid £5k a couple of years ago to replace ours (32kW boiler) and that included relocating the boiler to the outside of the house, fitting a magnetic filter, converting the system to a fully pumped s plan configuration, installing one larger radiator and plumbing in an under kitchen unit plinth heater.

Aside from the relative costs of replacing oil vs gas, as Buff has commented, the biggest unknown is the future price of oil and gas. In your position I think I would stick with oil but shop around for some more competitive quotes.
You should be able to get an oil boiler with a 10 year parts & labour guarantee (subject to annual servicing by an approved technician) and oil boiler servicing shouldn't be much more expensive than gas. 

Buff is also correct to ask about the maintenance/replacement of your tank. That is something to factor in when comparing costs of oil vs gas. You should assume somewhere in the region of £2k to £3k to replace the tank depending on size and location. And depending on age and condition expect to have to do this every 10 to 15 years. Many tanks will last much longer, but most of the plastic tanks usually only have a 10 year warranty. Safer to budget for a replacement at some point. 

drsquirrel

30% inefficent? meaning its 70%? Sounds non condensing.

Condensing only really get you over 90% in certain circumstances (return flow needs to be cold enough).

Replacement boiler in place should be 3k ish depending on how much you want to cheap out on the boiler (you could go lower).

Probably getting yourself an extra 10% efficency... for thousands in outlay.

I'd keep it until it dies. Oil boilers seem more modular too so maybe it could just have a burner replacement instead.

simoncorkswill1

turboace said:

My property is heated by a 20 year old oil boiler.  It runs ok but engineers say its about 30% inefficient. 

The property is a 1970s bungalow with a well insulated loft, cavity wall insulation, and double glazing. 

Quotes suggest costs to upgrade the heating system are £8k for oil and ££6.5k for gas, including connection.  My calculations suggest annual heating by oil would be about £350 cheaper or £550 with the predicted 20% increase.

What to do? 

Old boilers tend to be more reliable as they have a simple construction with less to go wrong , at 20yrs though yours may well have quite a few circuit boards etc I am talking about 40yr old ones , however if it ain’t broke don’t mend it . In terms of overall cost you will not recover replacing the boiler  in fuel savings , oil price has the benefit of going up and down , I aim to buy 500 litres at a time or more if price has fallen a lot , gas seems to have a one way trajectory.