Central Heating – which system

[redleader]

I’m worried my approx. 20 year old boiler will conk out soon and want to replace it before the cold weather starts. I’ve had a couple of heating engineers come round to look at it and they’ve given conflicting advice as to what system I should replace it with. I’d like to see what other people with a similar situation have done of if anyone else knows what I should do then please let me know!!

The house is a 3 storey, sandstone Victorian house (large rooms, high ceilings), 5 bedrooms, 2 bathrooms – but possible making more in the future, cast iron radiators. Boiler is currently in the kitchen and the hot water tank is in the upstairs bathroom. There are tanks up in the roof space but I'm totally confused what they're for!

Option A – install combi boiler (Valiet 937) - has a small internal water storage - I'm worried it won't have the capacity for the house

Option B – install new boiler – keep the same system – maybe replace the water tank

Option C – Install new ‘system’ boiler – I think I’m heading for this option but I’ve been told that my pipes might not be up to it and any leaks might not be found until they’ve done some damage.

WHich option would you go for?

[PigletJohn]

with two bathrooms, I'd go for an unvented hot water cylinder (often called Megaflo, but this is just one brand name). You can heat it from your old boiler until you need/can afford to change the boiler as well. Some old iron boilers are sturdy with not much to go wrong, but new ones are much more efficient and your gas bill may drop by a quarter.

The new cylinder will be much better insulated and economical than your old one, and probably quite a bit taller.

However, you will need a good incoming water flow, because you will no longer have a cold water tank in the loft, so you need the watermain to deliver water as fast as your taps can use it. Fill a bucket at the cold tap in the kitchen sink (and the garden tap if you have one), time it. How many litres per minute do you get?

You also need good flow if you go for a combi. It might be necessary to run a new pipe right out to the pavement in either case, if you do away with the cold water tank in the loft. You will be amazed what an improvement it makes. If you have an old house with lead pipes, get the water co to test your drinking water (free) for lead content. There might be a lead replacement subsidy.

Old lead, and iron, pipes are quite likely to be leaking by now, or to start soon, so this is a good time to think about replacement. Digging a trench across a garden is easy, but concrete drives and floors are harder. The new pipe need not follow the same route as the old.

If your radiator pipes are old, it is possible to get a new, modern, conventional vented boiler, which does not put them under pressure so less likely to find leaks.

We are now approaching winter and heating engineers will be very busy for six months when people urgently want their neglected old heating mended. People are more available, and sometimes cheaper, in warm weather.

[PigletJohn]

BTW before you put anything new on your system, or start disturbing it, have a system filter fitted (to trap sediment and sludge) and give it at least a chemical clean. Otherwise blockages or other damage may occur.

A filter costs about £100 plus fitting, and a simple chemical clean about £30 for chemicals, it can be DIY, otherwise half a day's work on top.

A powerflush will be strongly advised before you get a new boiler, but a filter and a chemical clean (get the plumber to show you how to empty dirt out of the filter) are a very worthwhile first step, and you can keep the filter with your new boiler.

[RandomMess]

What PigletJohn says, having followed his advice and got that system for our 5 bed 2-3 bathroom house. Fab showers and cheap bills!

[specialsubject]

to add to all this; if you have smaller pipes (8/10 mm) a powerflush is a waste of time. Chemical flush for older systems is the way to go.

start getting quotes NOW.

[WaitroseEssentialPancetta]

Piglet john bossed it again.

Does a megaflo system have drinking water in all cold taps?

[PigletJohn]

A Megaflo is for the hot water, but you would connect your cold taps to the incoming cold supply from the main (there is no cold water tank)

[RandomMess]

Something else good to know is that the expansion tank (I think this is what it is called a little baby tank???) doesn't have to go next to the huge storage tank so ours was able to be tucked away in some nearby otherwise dead space.

Something to bear in mind when deciding what to do is that it is relatively little extra cost in replacing pipes and radiators (although with cast iron certain costly) at the same time meaning that the plumbers are then entirely responsible for the whole thing working properly. The inconvenience and cost of having to drain down the whole system at some future point to have to replace, say one radiator etc - nightmare.

It may also be work installing the pipe work for future bathroom at the same time?