Central Heating question

[weakestlink]

We are currently renovating a big victorian villa starting things month by month as we have funds rather than borrowing or extending mortgage (until I crack!!!).

Anyway we can't afford a new boiler at the moment and as the current one (baxi Bermuda back boiler) is going strong it's not a priority. The house does take longer to heat up that our old (modern) house but it heats up fine and isn't cold.

We need to move a couple of radiators due to our structural work and I was wondering how much difference new rads will make as we could change them all to new ones while the system is drained... We are adding TRVs to few rads which don't have them anyway so should we just change all rads for new ones or is this a waste of time and best left until we change the boiler?

if your existing pipes are 15mm and 22mm, you can put new rads on if you want, may as well use bigger ones too. If the piping is microbore it will need to be thrown out anyway.

however be aware that if you add more rads onto an existing 15mm pipe, there may not be enough flow to feed more rads. Much better to Tee off a 22mm pipe.

I would recommend that you bale out all the mud from the feed and expansion tank, and run the system with X400 for a few weeks to loosen the old sludge before you drain it out. Use an inhibitor such as X100 on final fill.

This would be a good time to fit a (or the Sentinel one) system filter to start trapping the circulating sediment. I wouldn't have a Magnaclean as they are prone to leak.

BTW a Bermuda is very old now and due for replacement and there will be a lot of sediment, mostly black, which is liable to cause blockages and increase pump wear.

Thank you for the excellent advice.

What are the replacement options with very very limited external wall space (middle terrace with big bay windows). We do have excellent loft space if that helps?

Boiler was serviced in Sept and was told all a-ok for now...l

What about this ?

a modern boiler will go on the wall and can be the size of a small kitchen wall cupboard. It can go in a kitchen corner with easy connection to water and gas pipes, and the condensate waste pipe can easily connect, indoors, to the waste pipe, where it will not freeze.

Putting a boiler in the loft will be a great nuisance, it will be more likely to freeze, more difficult to get to and maintain, and more trouble to install. Try carrying one up a ladder.

I can't see any reason to buy another back boiler.

The only space in the kitchen is 400mm from the window edge to the wall. No other outside wall space due to windows / doors.... Apart for the loft which does have excellent access but will be converted to a bedroom / ensuite in a couple of years time. Would noise be an issue?

Wouldn't another back boiler be cheaper as no need to move pipes? Moving from current site in Dining room to kitchen is quite a way and floor would have to come up.

Also no gas in kitchen currently....

Hi weakest, I may be in a similar situation if I get to keep my house (currently going through the big D)

My boiler is about 20 years old but still going strong, hopefully. My pipe work is microbore though and chased into all the walls when the house was originally built.

piglet do you think this would all need to be replaced along with the currently crap rads and ancient boiler that I had knew i needed to replace anyway?

Sorry for hijack weakest, it's a nightmare trying to plan works that you have to do in stages as everything always seem entwined and dependent on something else needing to be done first! I will have to lose a rad when a wall is taken down but may end up having to live with heaters until I can afford to replace the entire ch system if needed.

wooden floors come up easily, especially as you are renovating.

Baxi is not a first-class make.

Pipe is cheap enough. Kitchens ought to have gas.

my boiler is very small. The flue can go up, back, or sideways, and can run along on top of kitchen units to the most convenient wall if not adjacent.

Spider
I think you should expect to replace the whole lot.

Thanks piglet, had a feeling that might be the case, bugger.....

Can I also hi-jack this?

We plan to add gas to our bungalow in the New Year (all electric at present!): we also plan to rip out and replace old kitchen. My desire would be to put boiler on outside wall and (because of limitations of size) cover it with a floor to ceiling cupboard which could then also be used to hold ironing board, brooms, mops etc. standing on the floor. How much ventilation would be required to this cupboard to satisfy the boiler (if we can do this at all)?

We are scarcely at the planning stage at the moment as we have to have a gas supply brought in from the road.

Ok piglet you have made a strong case for a new boiler...!

The pipework is 15mm as far as I can see and the upstairs rads were installed less than 10 years ago so they could stay and just change the downstairs ones for new and I would add 3 as well (currently none in porch, kitchen or study). Would also want the boiler to be large enough to cope with extra capacity when we convert the loft - say 2 more rads and a towel rail plus hot water for sink (shower would be electric though).

I will get a few quotes.... no idea how much really but can see online that the boiler itself is around £1k - could possibly confirm which model with the plumber and buy this on interest-free c/c to spead the cost if needs be.

I think labour for plumber round here is £180-200/day is this fair?

gotolder

modern boilers are almost invariably room-sealed with a balanced flue, and generally do not have any special need for ventilation. Have a look at the manufacturer's instructions for whatever you want to have. Vaillant and Worcester Bosch are two good brands (I have a Viessmann which I prefer, but they are not so common, so you need an experiemced local installer)i

Leave enough room all round the boiler for the cover to be taken off and the innards to be serviced. A modern boiler will usually be more powerful than an old one and is likely to need a new, larger gas pipe from the meter if the old one is just 15mm

weakestlink
The pipes to each radiator may be 15mm, but the pipes from the boiler, which the 15mm are tapped off, will usually be 22mm (28mm if a large old house)

Thankyou for your reply; I'm delighted.

As there is no central heating at present, only storage heaters, all the piping will be new - from the supply in the road to the final radiator!

We've just gone through a decision process as well re: radiators, new boiler or switching to a combi. It was a bit of a rushed decision in the end as our bathroom is currently being fitted (few pics on profile if interested! ) and that plumbing would also be changed slightly if we took the cold water storage out of the loft/fitted a combi (which is what needed to happen if we were going to convert the loft - so hear you on each decision being linked to another!)

As I understand it/the advice I got was if you're planning to convert your loft then you should probably be considering a combi as firstly you will lose quite a bit of space to the storage tank and secondly if you plan to have an ensuite in the loft then you'll really most likely need the increased water pressure a combi will produce (ironically the water pressure in our road is pretty crap though so might have looked further into megaflow had it all not got a bit too much like all the constant decision making was KILLING ME!).

As you've mentioned doing the loft in 'a couple of years' wouldn't it be better to put this in to place now rather than a stop gap that will also cost a fair amount of money and then be no good to you when you come to do the loft.

We decided against the loft in the end or else the combi would have been going in this week... as it was we replaced the older style radiators with double convectors that throw out much more heat (except in the kitchen where I went for pretty over function - it's a small room anyway and won't really need much in th eway of a radiator). This isn't our forever house and that also played its part.

All modern boilers have been reduced in max heat output than the older models as part of the energy saving "concept". They are also larger, not smaller, and no longer fit inside a small cupboard with a door. My daughter had a new combi-boiler installed after her old one broke down, but was too big to fit in the cupboard with the door shut.
My brother's 1984 boiler is also very small in the kitchen which fits into a wall cupboard, but a new one will be bigger he was told by the plumber.
My 24 W Worcester/Bosch combi is also much too big to fit in a small kitchen cupboard.

ps.
A new boiler must be installed by a CORGI registered plumber/heating engineer, and you must have a corgi registered certificate, that the installer will send you.

"All modern boilers have been reduced in max heat output than the older models as part of the energy saving "concept". They are also larger, not smaller, and no longer fit inside a small cupboard with a door"

I have to disagree.

Many old boilers were in the region of 11, 15 or 22kW output. Modern combis are generally in the 30 to 35kW output.

My 24kW Viessmann (not a combi) is considerably smaller that my old 15kw Potterton was, as well as far more efficient and uswing much less gas. It is capable of modulating its output down to 8kW for economy when not much heat is required, but will deliver full output when, for example, it is heating up a cold house and cylinder when the house has been unoccupied and set to Frost Protection.

BTW "Corgi" has been replaced as the authorising body by "Gas Safe"