Incorporating Solid Fuel Stove into existing heating system.

Mister Mac

Hi, I am looking for advice on the best way to incorporate a solid fuel stove into my existing heating system.

In a nutshell my existing system consists of an oil boiler heating the Rads, underfloor and DHW and solar panels running through Cylinder.

When building I had pipes ran to the side of my chimney breast to facilitate a stove at some stage. With the price of oil that stage has now arrived!

This is the breakdown of my heating system in more detail:

House is a dormer, system is a presurised system

The main flow comes in from the outdoor boiler it Tees one way into the Underfloor manifold system. all loops of the underfloor controlled by room stats , the other way via a motorised valve into the manifold for the downstairs rads,( underfloor downstairs except bedrooms which have rads)
Just before the motorised valve it tees upstairs to the manifold for upstairs rads via a motorised valve before manifold, and also into the cylinder coil for the DHW again via a motorised valve controlled by d tank stat.

When I install the stove I wish to be able to heat the down and upstairs rads. I do not want the stove to feed the UFH or run through the Cylinder.

My plumber has suggested changing the system to a open vented system and installing a new header tank in attic, or installing new circlating pump on stove loop along with a combination of non return valves and also a N/O motorised valve on the stove bypass loop( in the event of a power failure)

I have studied the system schematics and cannot see how the arrangement can be achieved if the UFH, DHW and rads are all calling for heat at the same time and the stove is lit and suppling hot water also.

Any advice appreciated

heinbloed

My plumber has suggested changing the system to a open vented system and installing a new header tank in attic, or installing new circlating pump on stove loop along with a combination of non return valves and also a N/O motorised valve on the stove bypass loop( in the event of a power failure)

Modern solid fuel boilers can be run with pressurised/closed CH systems.
They have safety valves build-in or allow for the inclusion of these, in case of a power failure.
Modern circulation pumps use so little energy that an emergency back-up via a car battery will suply the pump and control for many hours.

Contact a heating engineer for a detailed lay-out. Ask for an optimised CH system.

Think about an indoor (oil-) boiler, each boiler is a powerfull radiator in itself, it's thermal energy shouldn't be wasted to heat the environment.
Reducing this wastage could be more economical than installing a solid fuel boiler.

cabledude

heinbloed wrote: »

Modern solid fuel boilers can be run with pressurised/closed CH systems.
They have safety valves build-in or allow for the inclusion of these, in case of a power failure.
Modern circulation pumps use so little energy that an emergency back-up via a car battery will suply the pump and control for many hours.

I had a stove fitted last spring 2010 and was told by the stove retailer and 3 plumbers that under no circumstances could a boiler stove be fitted to s closed pressurised system. They all told me that what you'd be doing is making a potential bomb....

heinbloed

Cabledude wrote:

I had a stove fitted last spring 2010 and was told by the stove retailer and 3 plumbers that under no circumstances could a boiler stove be fitted to s closed pressurised system. They all told me that what you'd be doing is making a potential bomb....

They propably don't know what is available on the market. Or do not want to share their knowledge.
Boilerstoves in household size are available for up to 13 bar pressure.
And all boilers must have an over-pressure valve, a safety device letting out the steam avoiding explosions.

On the EU continent unpressured/open heating systems are hardly known. That is where the boiler stoves where developed.

Cheap copies of these are now sold in the UK and Ireland. But hardly as efficient as the originals.
An open/vented system always asks for thermosyphoning, waste of energy. And risk of freezing. And oxidation (rust) and sludge build-up.
And a damp attik, condensation.

heinbloed

Here is one of these safety valves designed for boilers with a max. pressure of 4 bar:

http://kotly.com/product_info.php?products_id=1771&language=en&topSsid=2984f

cabledude

heinbloed wrote: »

Here is one of these safety valves designed for boilers with a max. pressure of 4 bar:

http://kotly.com/product_info.php?products_id=1771&language=en&topSsid=2984f

It this what is knows as a pressure release valve.?

Carlow52

this thread is talking about soil fuel stoves, as discussed by the OP, and solid fuel boilers as discussed by others.

They are not the same, pressurized or not.

OP what temp is the ufh run at and if less than boiler temp how is it reduced?

heinbloed

The OP asks how to incorporate a solid fuel stove into an existing heating system and

...installing new circlating pump on stove loop along with ...

Many don't know the difference between a boiler and a stove.

Boilers prepare warm water, in short. Stoves don't, unless we call a cooker a stove and place a pot on it.

Cabledude asks about the link posted:

It this what is known as a pressure release valve?

Yes, a pressure release valve. A safety device.
But note that here with this valve cold water is mixed into the circulating hot water to cool it down, reducing therefore the temperature of the system. When the cold water from the mains enters the circuit a similar volume of water is released into the sewer.
It is not a plain blow-off valve similar to an emergency valve in the pressure cooker or a steam engine which would run dry after a while of releasing steam.
Click onto picture 3 at the bottom of the description.

As said before in this thread and previous ones: ALL boilers MUST have a safety valve, usually two. This mandatory valve can look differently than the one linked, it can have different limits/release pressures as well.
The risk with all pipe work is that it can be blocked, by debris or by error by false installation methods or sabotage etc... Here the blow-off safety valve as a last resource will help to safe lifes.

heinbloed

@ Cabledude:

Here a simple safety valve which blows off at 2 bar:

http://kotly.com/product_info.php?cPath=36&products_id=63&language=en&topSsid=50c1316a76b77d1bab0ed4a37da36bba

Only the water content/steam will be released. After this the boiler would be ruined - if it is running dry and the fire still burning.

martin3757

HI , I wanted to connect a multi fuel stove with boiler into my existing oil heating system , i asked the plumber that fitted the system , he said no because it is a pressurised system , looking at threads it may be possible , but im unsure with the technical side , any help , please .

heinbloed

....any help , please .

What sort of help ?

martin3757

help as in advice please , is it possible to connect using a magic valve ,

heinbloed

ALL thermal sources can be combined with ALL distribution systems.

Get a different heating engineer in, the one you have chosen seems to be incompetent. Check the yellow pages for adresses.

combine96

Mister Mac wrote: »

Hi, I am looking for advice on the best way to incorporate a solid fuel stove into my existing heating system.

In a nutshell my existing system consists of an oil boiler heating the Rads, underfloor and DHW and solar panels running through Cylinder.

When building I had pipes ran to the side of my chimney breast to facilitate a stove at some stage. With the price of oil that stage has now arrived!

This is the breakdown of my heating system in more detail:

House is a dormer, system is a presurised system

The main flow comes in from the outdoor boiler it Tees one way into the Underfloor manifold system. all loops of the underfloor controlled by room stats , the other way via a motorised valve into the manifold for the downstairs rads,( underfloor downstairs except bedrooms which have rads)
Just before the motorised valve it tees upstairs to the manifold for upstairs rads via a motorised valve before manifold, and also into the cylinder coil for the DHW again via a motorised valve controlled by d tank stat.

When I install the stove I wish to be able to heat the down and upstairs rads. I do not want the stove to feed the UFH or run through the Cylinder.

My plumber has suggested changing the system to a open vented system and installing a new header tank in attic, or installing new circlating pump on stove loop along with a combination of non return valves and also a N/O motorised valve on the stove bypass loop( in the event of a power failure)

I have studied the system schematics and cannot see how the arrangement can be achieved if the UFH, DHW and rads are all calling for heat at the same time and the stove is lit and suppling hot water also.

Any advice appreciated

Easy but not the cheapest way ( but has added benefits ...) is to install a buffer tank between your existing system and your new stove.


Added benefits first :

You would be able to run your stove near flat out for a while and make use of all the heat generated

Steadier supply of heat too the rest of the system , won't have to keep topping up the stove to keep rads warm as the evening wears on.

Much simpler setup , non-return valve and all that stuff fail/act up when you most need them.

You can just use an "ordinary" stove , readily available here in reality land instead of some magic yoke of questionable origin - buy Irish etc .

It means you can keep your sealed system - i believe these are better at reducing corrosion inside radiators as atmospheric oxygen can't sneak into the water circulating.


Roughly the same idea : http://www.firebird.ie/Portals/0/docs/4.3.4.%20Bio-Tec%20gasification%20boiler%20installation%20instructions.pdf

combine96

heinbloed wrote: »

Modern circulation pumps use so little energy that an emergency back-up via a car battery will suply the pump and control for many hours.

Car batteries are designed to live in cars afaik. Not powering heating pumps.
They are designed to handle the short high load of starting the car along with a bit of drain now and again as your suffer in stop n go traffic.

cabledude wrote: »

I had a stove fitted last spring 2010 and was told by the stove retailer and 3 plumbers that under no circumstances could a boiler stove be fitted to s closed pressurised system. They all told me that what you'd be doing is making a potential bomb....

You could make it safe-ish with pressure storage vessels and valves and and and sorta - much better to have it safe by design

heinbloed wrote: »

They propably don't know what is available on the market. Or do not want to share their knowledge.

o rly ?

heinbloed wrote: »

Boilerstoves in household size are available for up to 13 bar pressure.
And all boilers must have an over-pressure valve, a safety device letting out the steam avoiding explosions.

heinbloed wrote: »

On the EU continent unpressured/open heating systems are hardly known. That is where the boiler stoves where developed.

Last time I checked we here were not all speaking German ( and driving Mercedes ....)

Why ? simple stuff wins and .... the eu isn't always better

WW2 German aircraft had fuel injection , gave them an advantage.
Some lady in the UK aircraft plant just suggested adding a second bowl to the carb system so it would work upside down after being on what must have been inspiring trip to the loo.

heinbloed wrote: »

Get a different heating engineer in, the one you have chosen seems to be incompetent. Check the yellow pages for adresses.

heinbloed

Combine 96 wrote:

Car batteries are designed to live in cars afaik. Not powering heating pumps.
They are designed to handle the short high load of starting the car along with a bit of drain now and again as your suffer in stop n go traffic.

Obviously you haven't seen nor heard nor read about of what apeared on the market in last decade.

I run circulation pumps with car batteries. Check with your electrician for advise. Or buy the plumbing/heating press organs - and read them.