UKC

Hi.

Thinking we need to replace our gas boiler. It's been in place since Jan 2006 and leaks a fair bit, water and some green coppery residue. Had engineers look at it. Said it might last the winter. Model is an Alpha boiler, CD32C, a condensing boiler.

What model would UKCers recommend? For a three bedroom flat with seven radiators and one bathroom (bath and shower).

Look at boxt.  Went through them to replace our boiler in Dec 2017 - it had to be one of the coldest days of the year!  Fitter was excellent, arrived on time and neat work.  I'd selected the boiler using their online guide though the fitter recommended a smaller model, still Worcester, and my card was refunded the difference in price within a few days.

Did system pressure test, flush and fitted magnetic filter before the boiler went in.

See they are advertising on the telly box now.  

Cheers and happy heating...

We had a Wiessman fitted a couple of years ago. Fitted by British Gas. Stainless steel heat exchanger because we’ve got a water softener. Flushed the system and fitted a magnetic filter. Very pleased with the service.

Do you need to stay with gas or would switching to electric be a sensible move?

Worcester Bosch.  Not the cheapest but certainly reliable and reputable.

And DON'T get British Gas to fit it, they charge way over the odds, find a local person.

Switching to electric is never a sensible move for a home, your heating costs will go through the roof.  A heat pump may be worth looking at if viable, but I think they're borderline yet - I'd still suggest "one more boiler", they may be more mainstream by the time that one needs replacing in 10-20 years.

I've heard that they are living on reputation alone in recent years and that other makes are just as good now.

Some of the cheap companies like Baxi, which sometimes get a kicking on forums, are now offering 7-10 year guarantees on their more premium line boilers so can't be total crap if the company can afford to offer this.

I had a Baxi fitted back in  Jan 2012, it went wrong once about 8 months ago and cost ~£250 to replace, but a Bosch at the time was £500 more and would have been well out of warranty and probably equally expensive to repair.

Also, you can get a service plan on a boiler for £3 a month, covering you for breakdowns with a small excess to pay.

Worcester come with a 7 year warranty as standard, or 10 years for a small cost.

Had a Worcester installed at home in January 2017, no issues at all. The elderly Baxi in the house that my wife owns and we rent out has just failed and we have ordered a Worcester to replace it.

Vaillant or Bosch- I would try & find a local fitter with a good recommendation- then ask their opinion which model was most suitable. Also both these companies have good back up-

https://www.gassaferegister.co.uk/find-an-engineer/

That's outrageous. The boiler in our last house was over 25 years old and it's still going strong today. There needs to be a longevity law introduced methinks. 

I'd say think carefully about Veissmann - I've got one (came with the house). No one in our area knows much about them as they are relatively rare. Very complicated settings under the hood, I spent a lot of time reading technical manuals to get it to work with my newly installed Evohome heating system as the plumbers didn't have a clue!

While you have a point, I reckon in the next 10-20 years most people will have switched to air source heat pumps.  So there only really needs to be one more generation of boiler.

Why stainless because of a water softener?

Checking their website, only selected boilers get a 7 year warranty, some only get a 5 and to extend your warranty to 10 years (from 7) you have to use their specified installers and buy and fit extra filters (for extra cost obviously).

The Baxi boilers offering a 10 year warranty include the extra filters inbuilt.

As I said, there isn't as much between manufacturers as there was say 10 years ago. Other companies have caught up, although WB prices have dropped a small amount in comparison to others (probably recognising the above).

That's a shame: they get the better ratings (than Worcester)

Another vote for Worcester Bosch, pretty much all the plumbers I know recommend this. Its certainly not the cheapest in terms if initial outlay but you will probably get way more life from it. I have one in my house it has been grand since it was fitted several years ago.

We have BG boiler cover, so up to them if it breaks down. Very happy with the boiler and BG service. Works fine with our Hive. 

Because that's what the rep recommended was the best for our situation, and even on Worcesters web site, it stated which boiler they recommend if you have a water softener. 

We went with a Viessman.

I had a Vaillant installed last year and have the vSmart thermostat. Very happy with the system. It seems similar to the Hive app. Looking on the app is interesting to see the power level it uses. It only got to 100% twice so far and usually runs at 30-40%. 10 year guarantee at no extra cost as long as you use a Vaillant registered installer.

I didn't know it made a difference, whether you had a softener or not, we've got a softener and I don't think I'd be without one now. But I didn't know about matching a boiler to it, thanks for the info.

We have a Chaffoteaux, it's been great, it's not a condenser, but it's very efficient or was 20 years ago. Only had to replace the thermocouple once, other than that it just keep working.

Off to see what our HE is made of now, I think it is SS, but that's just by accident

I really wouldn't worry too much about that. The installer should be able to show you how to set the boiler up, and there should be a help line of some sort. I have a Worcester Bosch about 12 years old and it's completely reliable, but a couple of times a year I remove particles of aluminium that have come from the heat exchanger from the syphon.

Neither did I. When the rep came out to give us a quote, we told him we had a water softener and he then said there was only a couple of Worcester boiler that were suitable. The Viessman had a SS heat exchanger, so we went with one of them. I just think a SS heat exchanger sounds like its better made than an Aluminum one. We have an heat only boiler and still have a hot water tank.

Our water is very hard. Wouldn't be without a softener either. Our old Potterton Netaheat 16 boiler was 27 years old, we only changed it because it was kettling badly. Can't see this one lasting that long. If it hadn't been for the noise it made, we'd have kept it.

I would agree. Have had a Worcester Bosch for 17+ years. It is still going strong but hot water takes a while to arrive via taps + newer boilers are more efficient so we are having a new boiler installed. Plumber we use recommends Vaillant so, after, consulting WHICH, we are having Vaillant boiler installed. WHICH gives Worcester Bosch 90% satisfaction from customers / heating engineers. Vaillant gets 89%. Other boilers get around 60/65%. I think extra money for Vaillant will be worth it.

Modern boilers tend to have a pre-heat tank that at the expense of slightly poorer energy consumption keeps a small vessel of water hot for immediate delivery.  I turned this off, however, as the flow of my shower is too high for it so it'd go hot, cold, then hot again, which was really annoying, I also felt it a bit of a waste of energy.

I have no issue thus far with the boiler don't get me wrong, it works a treat (35 kW system boiler). It was just a very 'interesting' process getting it running nicely after a pretty much full re-pipe and radiator replacement. Stainless steel heat exchanger does suggest longevity but I'm no expert.

You really sure it needs replacing. They love saying it's knackered new boiler time. Our combi is at least 25 years old and there is absolutely no problem getting parts for it. Get someone who specialises in repair to have a squint before chucking it.

If so go electric combi then green tarrif, much better for the world. 

I know it's been mentioned elsewhere in this thread, but the current edition of Which magazine (Oct 2019) has an article on Boiler Reliability:

• Top 3 brands: Worcester Bosch; Vaillant, Viessmann
• Bottom 3 brands: Heatline, Ferroli, Biasi

It is right on the edge.  We're doing this right now, and for us, the cost of a heat pump, minus the cost of the new gas boiler, minus the RHI, and making some guesstimates about future savings, is more or less zero, depending on your electricity tariff and how you set things up.  Even if a bit more expensive you might consider paying 'green tax' worth it.

If you have solar PV to run the pump off, it's possibly now actually cheaper to go down the heat pump route. 

This does depend on having a heating system that's appropriate for the lower output of the heat pump - UFH or oversized rads.  If you have neither of those then the gas will still win out, cost-wise.

'If you have solar PV to run the pump off, it's possibly now actually cheaper to go down the heat pump route'

Of course, solar PV only generates electricity when the sun is shining, which is when you are least likely to need you heat pump.

Ahead of you already  - with Ecotricity for both electricity and green gas

You're still getting output on cloudy days, and due to heat effects on cell efficiency, you get a lot of output on cold, sunny days. Couple that to some home storage (i.e. a big battery) and you're generating a lot of your own needs. The "solar is useless because it's not sunny in the UK" argument is a bit out of date with modern PV panels and batteries.

On an hourly basis, a decent sized thermal store can cancel out the solar variation.  I'm probably going for a 1000L store so daytime PV running the pump will be able to heat the house overnight. I'll be timing the pump to run at the sunniest part of the day and making sure nothing else runs simultaneously.

The seasonal variation is obviously more significant. The store can tide me over for a day or two of poor sun but beyond that, yes, there'll certainly be quite a bit of grid import.

I do have solar panels myself, so I am familiar with how they work. The seasonal variation is significant - between May and July they generated 1580 kwh, while between November and January they generated 421 kwh. Of course it's on winter nights that your demand for heat will be greatest.

It depends on the cost of gas  - we don't have natural gas here, mains gas is butane/air mix and the most expensive heating option in the island. Oil is cheapest, then electric, then gas.

Of course.  My point is simply that, even without PV, a heat pump is now more or less cost neutral compared to a gas boiler once you factor in RHI and the CoP savings.  If that is the case, then having PV will therefore push it into profit, even if you still need to import some of your energy.

What is green gas?

We've got an Intergas which seems good (and various friends in the gas fitting trade are keen on this brand).

I think it is probably good to hae a fitter who knows the system they are installing.

A lot now depends on the electronics...got a 'Nest' which is good. Again a fitter who understands it is probably more important than the system.

Do wonder if we should have got a heat pump, but I think our house is not ideal for that.

https://www.ecotricity.co.uk/our-green-energy/our-green-gas/what-is-green-g...