Hot water - howto ?

OK - as there might just be someone with experience of gas boilers listening ...

We are currently planning some rebuilding work to our house, to replace a clutter cold and poorly thought out extensions with something that suits our purposes better.  This would involve a new kitchen. utlility, and a warm workshop for me

Currently the kitchen houses a gas boiler for CH and DHW.  It is a gravity fed system which I installed years ago (with a bit of help from a tame Corgi where legally required).  It is very tempting to think of replacing with a combi boiler to get all that cupboard space back. It would be nice to have a mains pressure shower. Maybe more eco not to have all that hot water hanging around, especially in summer. And the hot tank needs replacing anyway.  But - I have bad experience of Combis.  The old Gloworm in my previous home was terrible.  It wasted huge amounts of water before delivering hot and could not keep up with the flow rate to the bath taps. Heck, it even struggled to deliver a decent shower.  Are they good now ?  Can one be sufficient for 2 adults and a (not far off) teenager who likes wallowing ?  Do they deliver hot water without needing two days written notice

To answer your specific question, yes combi boilers are much improved, and you will get what you need BUT ONLY if you buy a good quality - Worcester Bosch or Vaillant.

However, for your family and circumstances, we (the man and I) would never actually recommend a combi. By retaining a hot water cylinder, you can have an immersion heater, so emergency hot water in the event of a boiler breakdown. If you install an unvented cylinder, you will have your HW at mains pressure. We would recommend a good quality system boiler (ie one that has the pump and expansion vessel inside the boiler case.

If you are employing builders to carry out the work, I would strongly recommend that you don't let them do the boiler work. Employ a Gas Safe registered central heating installer. I have seen so many shoddy installations carried out by builders' sub-contractors. It might cost you a bit more to do it that way, but providing you choose a reputable company, it will be cheaper in the long run. They will flush the system before installing a new boiler, make sure the gas pipe is sufficient, etc all of which help prevent breakdowns in the future.

Worcester Bosch boilers have far and away the best after sales service.

Happy to answer any other questions, but you might want to PM or email them.

Thanks for that. I am no hard core survivalist, but one of the things I like about having a wood burner is being able to be warm in a pretty self-reliant way on the event of breakdown or power cut - both have happened omce since we installed it. The lack of a backup plan without the hot cylinder had crossed my mind as being not great.

I suppose I should keep solar in mind - our roof is not at an ideal orientation though, and chatting to a Navitron guy I met at an agricultural show, he seemed to be steering me towards a PV system with immersion heater to dump unused power - largely to harvest subsidies I think.

I might PM you if I have any specific / off topic questions - thanks.

Neither do we have ideal orientation for our solar panels - our roof faces ESE, and also gets chimney shadow as the sun goes round. Our panels are purely thermal, so HW only, but we get significant gain from April to October. Even a sunny day in mid winter can give us a 13 degree rise. Not sure we could consider PV, as I know that partial shading can create problems.

Probably a good idea to do some homework before you make concrete decisions.