Condensing Boilers

[Endulini]

Hi,

I am currently looking to upgrade my boiler and was wandering what experiences people have had when buying the condensing boilers. My father was advised that he needed to change all the rads as none of the companies he approached would guarentee the boilers unless he did so. The advice I've had from the companies I've spoken to is that a power wash is sufficient if not a bit over-kill and a chemical wash would also do. I'm consciouss that the reputation of the condensors is that they are susceptible to crud in the system but the advice does seem somewhat confused.

Also anyone got some recommendations for decent manufacturers (for a 3 storey, 4 bed, 2 bathroom house)

Thanks

[Rob]

Very good, it uses a lot less gas than by old boiler behind the gas fire!

That's because they want to rip him off by fitting a whole new system. It's all down to money and how much they can make. Greed. Probably cowboy companies. Take no notice of people paying for adverts in Trading Standards Magazines, they offer no guarantee, don't inspect the work of people they recommend and it doesn't apply to subcontractors.

That's right, that's all I had on my system.

It's deliberately being confused in order to be used as "sales talk".

[John Stumbles]

Much the same as buying non-condensing boilers: just walk into the plumbers' merchants, pay some money and take it away. For a somewhat larger value of 'some' than the old ones, but hey! that's progress.

How many companies was that? He needs to try some others.

Condensing boilers in general probably have smaller waterways more susceptible to blocking, but some designs are more likely to be prone to this than others. There was a thought-provoking article in gas news about the potential for un-clearable blockage in the current poxi/batterton design with its multiple parallel waterways in a vertical circular arrangement. The current Worcester-Bosch design with its vertical axis seems to me inherently less susceptible, though it may have other weaknesses we haven't learned about.

[PC Plod]

I think many manufactures will only guarantee a boiler if the old system has been power flushed out. Saying that we had our system power flushed and the plumber then fitted one of these

Incredible product that actually works, after only 10 minutes of running the heating the magnet had a thick layer of sludge attached to it.

[PC Plod]

Vaillant is a well respected make and Worcester-Bosch is another

[Andy Hall]

Which wouldn't be needed had he cleaned the system properly and if a corrosion inhibitor was used and maintained. Keep in mind that this is treating the symptom and not the disease. The system is continuing to corrode and deteriorate and the radiators are likely to develop holes and leak.

With correct system design and use of inhibitors, radiators will not produce sludge and will last for decades.

[John]

We had an Alpha CD32C condensing combi installed about two years ago and it's brilliant, especially when coupled with the Wireless 7-day EasyStat programmer/timer thingy, and it comes with a manufacturer 3-year warranty. We had a complete new system installed because the old system was what I believe is called a "Primatic" system - only one header tank in the loft and no way to insert chemical inhibitors etc., into the system so rads needed far more than a powerflush.

John

[dennis]

Collects iron oxide from where exactly? Did he flush the crud or no? If he did there shouldn't be any iron oxide to collect. Check he put inhibitor in the system and it isn't fresh corrosion or your system won't last long before it leaks.

[Ed Sirett]

Various ppl have given quite sensible answers, i.e. ones I agree with. A lot more info is in the boiler choice FAQ.