Navitron Renewable Energy and Sustainability Forum

BIOMASS => General => Topic started by: reggieroo on August 31, 2009, 01:54:17 PM



Title: Hooking up the back boiler to a new condensing boiler to save on fuel bills?
Post by: reggieroo on August 31, 2009, 01:54:17 PM
I've been thinking about hooking the back boiler back up with a neutraliser to a new regular boiler (my old 25 year one has given up) to save on LPG costs. I had a chap out the other day & told me that the back boiler will only heat the water & not the radiators as it's not that big & to work out if it will make me any savings over the year. I have a coal/log fire nearly every night in Winter so thought it would be wise to use the back boiler so I'm not just wasting the energy.

I was then thinking doesn't your hot water heat up anyway when your central heating is on, which would be on most of the Winter anyway?
So is it worth the extra expense of hooking up the back boiler as the water would already be hot from the central heating wouldn't it?

I can just go for a combi & not bother with the back boiler or get a new regular boiler & hook up the back boiler, just not sure what to do.




Title: Re: Hooking up the back boiler to a new condensing boiler to save on fuel bills?
Post by: dhaslam on August 31, 2009, 02:03:13 PM
There is a lot to be said for not connecting a small back boiler to the hot water system.   The water jacket in the stove lowers the efficiency of the stove which means that you burn more fuel.   If your stove works efficiently for space heating you will be saving a lot of gas anyway and possibly make a net saving. 


Title: Re: Hooking up the back boiler to a new condensing boiler to save on fuel bills?
Post by: reggieroo on August 31, 2009, 02:13:14 PM
Its a small open fire in the lounge & heated the room pretty well last winter while we had no central heating. The rest of the rooms we used had some oil filled radiators to get us through as our old boiler gave up the goose last Xmas & we have been without central heating since but still had hot water as I have the immersion in the airing cupboard.

My dilemma is what boiler to fit to save me money over the coming years & weather to reconnect the back boiler up the the system.

I've been told just to fit a combi, not bother with the back boiler & be done with it but I would like to use it if possible, providing that the extra cost of fitting will make me some savings.



Title: Re: Hooking up the back boiler to a new condensing boiler to save on fuel bills?
Post by: sleepybubble on August 31, 2009, 03:44:37 PM
SOunds like you have a Baxi fireplace, my first thought would be... Why was the back boiler disconnected? and has it been made safe when it was disconnected so that you can use the fireplace as a fireplace?

Quite often folk will have a back boiler disconnected because it has started to leak and its just cheaper/easier to sling in a modern boiler? Or folk will sling in a modern boiler at which point the back boiler gets disconnected and is then made safe. To make a back boiler truly safe it would be quite common to drill holes through it, as filling a baxi with sand is pretty hard to do, due to the nature of how they are fitted (built in).

If niether of the above actions were undertaken when the back boiler was decommisioned it may have suffered corrosion since. I'd reccomend getting somebody in to test the back boiler before going any further in the thought of re-comissioning it.

Proberbly not what you want to hear but....


Title: Re: Hooking up the back boiler to a new condensing boiler to save on fuel bills?
Post by: guydewdney on August 31, 2009, 08:19:38 PM
some basic questions:-

does the room that the wood burner is in get stiflingly hot? Or do you turn it down (reduce air intake a lot etc)? Either way would show that there is 'extra' heat available.

A back boiler / clip-in boiler is no small task. If the above is true, then you can heat somthing (hot water at least - or add to the heating a bit) with some cleverness... But if you have a tiny stove - then is it worth it?


Title: Re: Hooking up the back boiler to a new condensing boiler to save on fuel bills?
Post by: reggieroo on August 31, 2009, 08:56:41 PM
Well from what I've been told the back boiler was disconnected because the previous owner of the house was disabled & wasn't capable of getting a fire going so they disconnected it & fitted a regular boiler for her instead so she had central heating & hot water without any fuss.

The current regular boiler I have in place is around 25 years old so I'd imagine that the back boiler has had no use for 25 years. The pipes have just been cut where they go into the airing cubboard so it has been made safe, as for corrosion hard to tell & nobody is really interested in having a look for me. All the plumbers I get out are only intersted in fitting a combi boiler & most don't even give a quote when I ask about hooking it back up. Only one has so far & the cost was sky high 4800 to connect it back up & fit a new regular boiler!!!  :o


Title: Re: Hooking up the back boiler to a new condensing boiler to save on fuel bills?
Post by: desperate on August 31, 2009, 09:31:22 PM
Hello regieroo

that price is not cheap, but it  doesn,t sound exactly sky high to me I,m afraid, round here people are paying about 3000 plus for a straight boiler swap, and messing around with a 25year old BB sound like grief to me.

Sorry


Desperate


Title: Re: Hooking up the back boiler to a new condensing boiler to save on fuel bills?
Post by: Solal on August 31, 2009, 09:48:31 PM
Disconnected  my Dunsley  about  10 years ago and  filled  the pipe ends with expanding foam.
There's no way  I would  consider  connecting  this back into the system again  as  its bound to be  corroded inside.


Title: Re: Hooking up the back boiler to a new condensing boiler to save on fuel bills?
Post by: reggieroo on September 02, 2009, 07:51:03 PM
Most people don't seem to like the idea of hooking it back up, I just thought it might save me some cash in LPG bills.

I spoke to one chap today who is doing me a quote & he's up for doing it. He mentioned using a twin coil cylinder instead of a neutraliser as he said it would be cheaper, after he's checked if its still ok.

I'm still wondering is it going to save just as much in fuel bills fitting a combi?


Title: Re: Hooking up the back boiler to a new condensing boiler to save on fuel bills?
Post by: Brandon on September 02, 2009, 09:11:03 PM
put in a direct thermal store with a solar coil, and insulate as much as is physically possible (as opposed to as far as you are prepared to "ruin" the "character" of your house.

Then sit back and laugh at the rising price of LPG. ;D