Replacing gas boiler - BER C3 rating

Geuze

Just bought a house, built 2004, BER rating C3, 150 sqm detached.

Ferroli Tempra 24 gas boiler, BER says it's 78% water and space heating efficiency.

Two zones, i.e. two thermostats, upstairs and downstairs, no separate water zone.

One of the four showers runs off hot water, i.e. it isn't an electric shower.

Got an RGI to look at boiler, it hadn't been serviced, got it working, but the timer clock sparked.

So now no timer.

I would like to upgrade the boiler as I feel it's not the best.

RGI recommended Viessmans, it seems he is a registered installer.

• He said something like the 5yr warranty is extended to 10yr if he installs it, and services it.
• He mentioned 2,500 for boiler.
• He mentioned adding third zone on water cylinder.

This could all be a sales spiel, but they do seem like good gas boilers.

My questions:

(1) I read here that it's not much use replacing boiler unless house is well insulated. So am I wasting money on a new boiler with a C3 rating?

(2) Should I try to improve C3 rating first?

(3) Are Viessmanns a good boiler?

(4) What model would I need for 14 rads, of various sizes.

Vitodens 100-W or 200-W?

https://www.viessmann.co.uk/products/gas-boilers/vitodens

What KW output?

(5) I think I would qualify for the 750 boiler heating control grant?

I really, really appreciate any advice.

Idbatterim

It’ll be a fair while before an eighty odd percent efficiency gas boiler pays back the 2500 ...

Geuze

Thanks.

The Vitodens 100-W is "High efficiency - SEDBUK 2009 seasonal efficiency: 89.5%"

Is this what you are referring to?

So your point is that the efficiency increase from 78% in the BER to 89.5% isn't much for the large capital cost?

Geuze

https://www.homeheatingguide.co.uk/efficiency-tables?make=Viessmann

The 100 and 200 models all seem to be around 89-90%.

Dardania

Geuze wrote: »

Thanks.

The Vitodens 100-W is "High efficiency - SEDBUK 2009 seasonal efficiency: 89.5%"

Is this what you are referring to?

So your point is that the efficiency increase from 78% in the BER to 89.5% isn't much for the large capital cost?

Totally agree with idbatterim, and your summarisation of his point.

If I was doing any capital investment, it’d be first for improved controls (I think SEAI are still offering a grant for this,) and then if the main heating plant is beyond economical repair, for a heat pump of some configuration.
If theb irsh government grows a pair of balls, they will carbon tax gas and oil boilers to extinction, so are you willing to take the risk of buying a 15-20 year lifespan item of plant which ought to be taxed out of feasibility before 2030?

rightjob!

Dardania wrote: »

Totally agree with idbatterim, and your summarisation of his point.

If I was doing any capital investment, it’d be first for improved controls (I think SEAI are still offering a grant for this,) and then if the main heating plant is beyond economical repair, for a heat pump of some configuration.
If theb irsh government grows a pair of balls, they will carbon tax gas and oil boilers to extinction, so are you willing to take the risk of buying a 15-20 year lifespan item of plant which ought to be taxed out of feasibility before 2030?

There is alot more to it than just installing a heat pump.
A heat pump would be a waste of money in a house that in not air tight.

The Viessmann is a great boiler,you will qualify for the grant if you get heating controls done and it is definitely worth while getting them.

DGOBS

Fitting a heat pump to a house that does not meet the correct insulation criteria, would be like trying to keep your fridge cold with its door ajar.

Don't get me wrong, heat pumps are fantastic bits of kit, but would only be suitable for new builds or older houses that are undergoing a deep retrofit for insulation.

Geuze

Thanks for all comments.

I had ruled out the heat pump as that requires new pipework / new cylinder?

I accept that carbon taxes will be increased, but I assume that any carbon tax on gas is low, as gas is cleaner than oil?

https://www.bonkers.ie/guides/gas-electricity/what-is-carbon-tax%3F/

What does the carbon tax cost me on my gas bill?
Natural gas suppliers in Ireland, such as Bord Gáis Energy, Electric Ireland and Energia, are all obliged to add a carbon tax charge to all customers' bills, which works out at 0.42 cent (including VAT) for every kWh of gas used.

Considering that the average Irish household uses 11,000 kWh of gas every year, the carbon tax adds around €46.20 to your annual natural gas bill, which works out at around €7.70 on every bi-monthly bill.

Carbon tax is not applied to electricity bills (although here there is the PSO levy).

Oil

https://www.revenue.ie/en/companies-and-charities/excise-and-licences/excise-duty-rates/mineral-oil-tax.aspx

50.73 per 1000 L.


Hmm, the carbon tax on oil is not much lower than gas........

Dardania

Geuze wrote: »

Thanks for all comments.

I had ruled out the heat pump as that requires new pipework / new cylinder?

I accept that carbon taxes will be increased, but I assume that any carbon tax on gas is low, as gas is cleaner than oil?

https://www.bonkers.ie/guides/gas-electricity/what-is-carbon-tax%3F/

What does the carbon tax cost me on my gas bill?
Natural gas suppliers in Ireland, such as Bord Gáis Energy, Electric Ireland and Energia, are all obliged to add a carbon tax charge to all customers' bills, which works out at 0.42 cent (including VAT) for every kWh of gas used.

Considering that the average Irish household uses 11,000 kWh of gas every year, the carbon tax adds around €46.20 to your annual natural gas bill, which works out at around €7.70 on every bi-monthly bill.

Carbon tax is not applied to electricity bills (although here there is the PSO levy).

Oil

https://www.revenue.ie/en/companies-and-charities/excise-and-licences/excise-duty-rates/mineral-oil-tax.aspx

50.73 per 1000 L.


Hmm, the carbon tax on oil is not much lower than gas........

Doesn't necessarily need new pipework and cylinder at all. Although as other posters point out, it might drive not insignificant air tightness and/or insulation upgrades, depending on the build quality of your house.
SEAI have some sort of a partial grant for an assessment of suitability for a heat pump - see the details here:
https://www.seai.ie/grants/home-energy-grants/heat-pump-systems/
Maybe your house is built relatively well, and capable of taking a heat pump without too much hassle - or is it highly draughty / cold even with the heat on?

RE carbon tax, my point isn't what the carbon tax is now. My point is that it needs to increase, big time, for all of our health, and if that happens, you will have spent an amount of money on a new boiler which you expect to have for 15 to 20 years, and be locked into paying the carbon tax on. See here:
https://www.irishtimes.com/news/environment/massive-hike-in-carbon-tax-needed-if-ireland-to-meet-targets-esri-1.3704655
and bear in mind Eamonn Ryan of the Greens managed to get an all parties agreement that all parties would support this approach.

If you go down the gas boiler route, as another poster mentioned, there are grants for better controls which are well worth while. In fact, maybe you just need new controls, and keep your current boiler chugging along:
https://www.seai.ie/grants/home-energy-grants/heating-upgrade-grants/

Charlie 08

isn't the SEAI grant for heat pumps for houses around the C1 BER?