Thouhgts on a new boiler - Combi?

diywhynot

Find a recommended RGI to have a look, discuss your requirements and advise. Have your boiler serviced, replace the pump and HW cylinder, have system flushed, have a magnetic filter fitted, insulate pipework or replace boiler and cylinder. Weigh up the costs and decide which is the money saving option for you and fits in with your long term plans.

MillicentBystander

blogger57 wrote: »

A few points to consider

Instantaneous Electric showers
Depending on kW power, an electric shower can produce around 4-5 litres of water/minute in the winter (more in the summer as the incoming water temperature is higher). Some people think this fine and it is certainly much better than a dribble. Personally I prefer a high pressure mixer shower which can deliver 9-10 litres per minute.

The higher rated 10.5kW electric showers take around 45 Amps. Older houses used to have a 60 Amp mains supply and newer ones tend to have 100 Amp supply. So before investing in an electric shower (or two as someone suggested) you need to find out what the total power supply to your bungalow is. Putting the electric shower and the cooker on at the same time could cause you problems.

New Boiler
A new 'A' rated condensing boiler is rated at being 90% efficient. Depending on the age and condition of your old boiler it could be 50-70% efficient. So it is perfectly reasonable to assume that if you were spending £1200 year on fuel that you could save £300 year on reduced fuel usage. Whilst this may not pay for all your spend, depending on your circumstances you may get a payback.

If you are doing this then make sure the rads are flushed and put a magnetic filtration system on the radiator circuit to avoid the sludge problem in the future. Also I would suggest TRVs on the radiators (except for one) to get the heat where you need it.

If you are experiencing problems which lead to costly heating engineer callouts be aware that most modern boilers come with at least a 5-year warranty.

Hot water cylinder replacement
If I were replacing a hot water cylinder now (for a high presure system rather than an unvented system as you currently have) then I would certainly go for a twin coil cylinder to give the option of using other forms of energy to heat the water in the future i.e. biomass or solar water heating.

Investing in solar water heating does not have a great return currently but there is a £600 grant for those putting it in. Also the government is due to announce the details of the Renewal Heat Initiative during the Summer which is likely to give payments per kW of energy generated by solar water heating panels. This will change the attractiveness of this investment.

Hope this helps. Good luck with your project.

Firstly, who has said the OP is spending £1200 on GAS (not 'fuel' as you suggested)? And even if he/she was, there is STILL an argument to delay the new boiler until the old boiler has died simply because the longer the OP leaves it to replace the old, reliable boiler with a new, not so reliable but sophisticated one the longer he/she should have the new boiler last.

ahar_2

macman wrote: »

If you are putting in an ensuite soon, why would you even consider a combi? No combi can supply 2 bathrooms simultaneously.

I had been looking at one of he combi boilers with attached storage - the vaillant 937 can provide 20 l/min using these for up to 10 mins, so on the few occasions where the showers run simultaneously it could supply 10 l/min to each.

I measured the output if my current shower (using the bucket, stopwatch and maths method) at 10 l/min and I'm perfectly happy with it.

However, I know that if anyone turns on a tap while both showers are running, it'll all go horribly wrong.