Question about installing a wood boiler stove

[lennox]

Hi

I am going to install a wood boiler stove for central heating and hot water. I have the instruction manual which states " A safety relief valve should be fitted to the expansion pipe close to the boiler"

Can anyone explain exactly what the safety valve is and how it would work in this setup.

Thanks

Lennox

 

[justlead1]

Hi, A safety valve on this type of installation (open vented ) was quite common it is a spring loaded valve (the jumper being held down by the spring) in the event of pressure building up in the system the spring would be overcome by the internal pressure and allow water to pass, reducing the system pressure, but spraying super heated water over the living accommodation. Some manufactures copy dated info and publish. There are more sophisticated methods of protection now that can be piped to a safe discharge point. However good frost protection of the vent pipe will go a long way to avoiding such events. Good luck

 

[lennox]

Thanks for the reply, Is a safety valve just the same as a expansion relief valve, that is used on an unvented system?

 

[migoplumber]

yes it is lennox, but dont go there without specialist advice.
shaun

 

[lennox]

I'm hoping to get specialist advice here!! Would it be correct procedure to have a discharge arangement from the expansion relief valve to a tundish discharged outside the property???

 

[migoplumber]

sorry lenox, but youve asked the same question on different threads, you dont know what you are doing judging by your answers, and its not a case of being rude, i would love to help you, but you need some basic fundamentalist knowledge in not killing people. i wont post to you anymore, sent you a private message explaining what could happen. google it, then you can blame google when you do vaporise some womans head off.

 

[lennox]

Shaun, I put it on a different thread because there was no response on this one at first. What are forums for? I think you are being very negative and rude. If you can't help then don't.
Lennox

 

[migoplumber]

didnt mean to sound or be rude. my apologies. good luck.
shaun

 

[buffy27]

lennox,whats the craic.
are u going to go ahead with this your self against migo s advice.what ever was said in the private messages between ye i don t know but he obviously has reason to be questioning your knowledge.
if u are in anyway unsure don t attempt this work.even seasoned plumbers run into difficulties with open vented heating systems,especially when they are used in dual systems etc.

 

[lennox]

Shaun,
Apologies accepted

Lennox

 

[buffy27]

lennox are u going ahead with the job

 

[lennox]

Yes of course!!! I was just unsure what the safety valve was for on the vent pipe. It was kindly explained to me by another member. What was shaun going on about i haven't a clue, but it was very negative. I am a full time property renovator, even though I don't trade solely as a plumber. I have a city and guilds in plumbing installation, unvented cert and b pec solar installation cert. I've installed 2 solar domestic hot water systems in the last 2 weeks... so why shouldn't I install a wood boiler stove????

 

[buffy27]

whats the craic.
how many rads . what size boiler kw output.where is it located.location of f&e in relation to cylinder{type of cylinder ,indirect,direct,single or dual coil]
is there a second heating medium in the house and how is this piped in relation to the existing system.
the safety valve is the least of your worries[the spiders will be living in it for years if the system is set up right ,ie it won t ever blow off] i do alot of this type of work and can help.be accurate in the details and honest with your abilities and i will help u .answer the above questions first and we ll take it from there .

 

[lennox]

The system will have 5 rads plus a heat-leak rad.
boiler stove is a villager 14kw.
stove located on the ground floor.
cylinder on the first floor.
210lt unvented indirect single coil cylinder (maybe a twin coil for solar)
f and e tank in the loft.
No other heating system.

lennox

 

[plumbnuts]

Lennox
I am not registered for solid fuel, however I am sure that you cannot connect a wood burning stove to an unvented cylinder as there is no control over the amount of heat produced by the burner.
Steve

 

[lennox]

Steve,
I thought the same as you, I emailed villager tech dept the question, with a diagram. They replyed :
Assuming the cylinder itself has the usual safety valve set up to deal with excess pressure in the cylinder, there is nothing wrong with what you propose to heat the water at all – the coil in the cylinder, and the remainder of the circuit is vented by the F&E system you have drawn, so no problem.

Regards

Richard


Villager Stoves
Millwey Industrial Estate, Axminster, Devon, EX13 5HU
Telephone: + 44 (0) 1297 35596
Fax: + 44 (0) 1297 35900
Web: www.villager.co.uk

Lennox

 

[plumbnuts]

Richard
As I thought it's a big no no. I have looked at my course notes albeit they are 7 years old and it states that under no circumstances can a unvented cyl be connected to a solid fuel boiler as it's primary heat source as the temperature is not controlable. You must remeber from your G3 that heat=pressure. I would be inclined to recontact the manufacturer and explain the situation again. How could you regulate the temp of the DHW and if done by the normal means i.e cylinder stat/thermal cut out and motorised valve where would the excess power go once the cyl reached temp?
Regards
Steve

 

[justlead1]

Hi Lennox. I think they have given you bad advise, and may live to regret it if you install. Check out regs. G3 comes to mind. Check out this link. Un-vented hot water heating systems Good Luck

 

[lennox]

I will contact villager again tomorow. I fully undestand that a wood boiler stove is uncontrolable heat, but so is solar. Why can solar heat an unvented cylinder but not a wood boiler stove?

 

[buffy27]

i think it can be done.
if the heating is left open vented,with an f&e tank .think of the coil as an additional rad to the 5 new rads. allow it heat the cylinder by convectional heat currents and with a pipe stat on the flow set at say 65/70degrees have it teed into the rads with a pumping into the rad circuit. making sure that the expansion pipe is workable at all times,put a gate valve on return from coil before the t into the heating.have this slightly closed.the pump will push the water through the rads and make its circuit[path of least resistance.].
u could also do it with a pump at the back of the b boiler.there would be a stat on the flow to activate the pump [pump must be on ret to boiler allowing the expansion pipe to work at all times]i put in a 4 way blending valve with the pump between b boiler and blender,this works as a by pass,and mixes the tempeture back a tad with returning water from heating being cooler.up in the hot press then u tee to rads and coil with gate valve cracked slightly.
i have done a few ti-sun cylinders [sealed systems]
blending valve ,pump ,expansion vessel!!!!yes expansion vessel.
i always put a 3 bar blow off at b boiler piped to outsid on all my installations[spiders are living in all the ones i have done so far]
i always install temp relief valve on dhw.. come on with the questions.i will answer all.

 

[plumbnuts]

Buffy
With respect and as said you are not allowed to connect solid fuel heating to an unvented cylinder.

Richard
Solar is different and requires a drainback unit/ thermostat and suitable controls. This will control the temperature of the dhw in the cylinder and meets the building regs.
Steve

 

[buffy27]

Buffy
With respect and as said you are not allowed to connect solid fuel heating to an unvented cylinder.

Richard
Solar is different and requires a drainback unit/ thermostat and suitable controls. This will control the temperature of the dhw in the cylinder and meets the building regs.
Steve

check out the ti sun cylinders -thermal stores.i ve done about 8 in the last year.they come with scematic detailed drawings. i don t do anything that may damage my so far good name. i do nothing absolutely nothing unless i am 100percent certain i know what i am at.was expecting your reply.we do alot of this type of work the boss is operating with 22yrs now.all private large houses when we do domestic stuff.

 

[stevetheplumber]

in this case would a heatstore system be better ?still mains fed hot water but open vented and no blow out pipes from the cylinder to run not something i know much about and would be interested to hear others comments on this set up

 

[plumbnuts]

Buffy
No offence meant and I'm sure you do a good job.
You are talking about thermal stores which are a different ball game altogeather, the topic got onto unvented cylinders and solid fuel
Steve

 

[buffy27]

Buffy
No offence meant and I'm sure you do a good job.
You are talking about thermal stores which are a different ball game altogeather, the topic got onto unvented cylinders and solid fuel
Steve

the heating loop in the thermal store is a closed circuit was what i was sayin and we do the solid fuel systems in the same type of manner.

 

[plumbnuts]

The thermal stores have an overheat protection and will discharge water to drain in order to lower the temperature, unvented cylinders do not and cannot control the temp from solid fuel although they are a far better system and not so prone to limescale build up as thermal stores. However thermal stores can be connected to a gas boiler, solar, electrical heating and solid fuel or all four at once.
Steve

 

[buffy27]

The thermal stores have an overheat protection and will discharge water to drain in order to lower the temperature, unvented cylinders do not and cannot control the temp from solid fuel although they are a far better system and not so prone to limescale build up as thermal stores. However thermal stores can be connected to a gas boiler, solar, electrical heating and solid fuel or all four at once.
Steve

spot on steve from what i know of thermal stores.
back to the back boilers...our systems seem to work perfectly with the addition of blow off pressure and temp. maybe its technically incorrect but i have not made this up myself only learned it from the company i work for.the boss is a mechanical engineer with 40 yrs plumbing experience.apparently he is very highly regarded in ireland.one of the first registered solar,heatpump,air con installers in the republic as they came on line over the years.i value your comments .things are more strict in the uk as regards regs.we are a tad behind on the paper work stuff.i can only vouch for work i have done and seen done from personnal experience.

 

[plumbnuts]

Too much red tape in the UK Buffy!

 

[migoplumber]

solar heat is controlled, it has or should have a pump and by pass incorporated on the pipework between panels and cylinder, operated by the controller and pipe stats.
shaun

 

[buffy27]

solar heat is controlled, it has or should have a pump and by pass incorporated on the pipework between panels and cylinder, operated by the controller and pipe stats.
shaun

did u post this on wrong thread.what are u talking about here.

 

[migoplumber]

oops, soz buffy and cheers.
shaun

 

[leakylea]

the stove will have an amount of water in it,the relief valve should be as close as possible,in case the circs comming of it are isolated or blocked.
without the relief valve the stove would super heat the water, resulting in the stove exploding throwing red hot , water and steam over every one in the room, if you were lucky to miss the water the burning wood and the embers would ignite what was left of the room and its hysterical occupants. picking white hot cast iron off their burned scalded bodies
if you dont know don't do

 

[buffy27]

the stove will have an amount of water in it,the relief valve should be as close as possible,in case the circs comming of it are isolated or blocked.
without the relief valve the stove would super heat the water, resulting in the stove exploding throwing red hot , water and steam over every one in the room, if you were lucky to miss the water the burning wood and the embers would ignite what was left of the room and its hysterical occupants. picking white hot cast iron off their burned scalded bodies
if you dont know don't do

lee i am beginning to consider my part in the death of some poor unfortunate as a result of this job.
lennox. i stated already that even experienced plumbers would have difficulty with such an installation.i am only fortunate to work alot on this type of thing and thats why i tried to help.if u are going ahead with this u need to post drawing of what u are going to do exactly. p.s can u leave the b boiler open vented altogether.

 

[migoplumber]

sorry lenox, but youve asked the same question on different threads, you dont know what you are doing judging by your answers, and its not a case of being rude, i would love to help you, but you need some basic fundamentalist knowledge in not killing people. i wont post to you anymore, sent you a private message explaining what could happen. google it, then you can blame google when you do vaporise some womans head off.

At the end of the day, this is a website for burying our own super plumber ego, and for helping and advice, both giving and recieving.

sometimes the best help is no help !!

shaun

 

[lennox]

Hi Buffy, thanks for the advise you have gave to me. I have made a drawing for my proposed installation can I e.mail it to you for your coments.

regards

lennox