Combined T&P relief valve

[Nordio]

I'm just about to plumb in my new air assisted 40kw solid fuel boiler in combination with my oil boiler which is in my garage.

My current system is vented so I will be maintaining this and using a couple of nrv's to prevent backflows.
The cold feed and expansion pipe will have a clear path to the boiler but the flow pipe has no clear path to vent.

I have an idea I will probably use but would like to hear from the professionals how you would acheive some level of safety in the system without going to too much expense.

Nordio.

 

[stem]

Combining boilers in practice, is not as straight forward as it might appear. Use a neutraliser for linking two heat sources. You can download a brochure with diagrams here

 

[Nordio]

The neutralizer would mean to much pipe work.
Thanks but not an option.

I want to use a T&P valve on the solid fuel boiler outlet to cater for an over heat discharge @90c as the path to vent has a circulator, nrv and zone valves.
Is this feasible?
The cold feed is unrestricted.

 

[Biggles..]

have a look at Nabic valves, that said your idea is a bodge, mutiple heat sources should be combined by neutraliser,thermal store,low loss.All of these alter the neutral point.

Obviously your not Heatas registered either for your solid fuel

 

[Nordio]

I don't think it will be a bodge.
Seen one yesterday installed on a sealed system although it was converted over to pellets but he changes back to logs when he builds his stock pile up.

The plumber just T'd into the oil boiler primary f&r with an nrv on the solid fuel stove flow.
He plumbed it all in within a day.
You can see my boiler here... The KSW plus 40kw....
http://www.per-eko.pl/?-b-seria-ksw-plus-b-,37

Its a real beast and weighs in at a hefty 330 kilos. Had to shift it into place with a telehandler.

How much would you guys be quoting to install this?

 

[transam]

Soild fuel wood burner on a sealed system ????? how has he acheived any over heat protection ????

 

[Nordio]

The fan shuts off when the set temperature is reached via the ST-28 controller.
There is also an auxillary bi-metal sensor in addition to the furnace sensor which cuts off the fan operation when 85c exceeded.

An air flap (which is settable through an adjustable balancing pivot) then prevents the flue from drawing air also.
An alarm is activated if an excess temperature occurs.
An alarm is also activated if the furnace sensor fails.
Its all very safe.
Heat leaks or great whopping thermal stores are not needed.

 

[transam]

Interesting !! so the boiler is designed to be fitted to a sealed system ??

 

[Nordio]

Interesting !! so the boiler is designed to be fitted to a sealed system ??

Well thats what I was led to believe but don't quote me.
It looks a very neat installation from what I seen. Its a new build.

The set temperature on the controller needs to be set about 10c lower as an overshoot will occur.

My system is vented though and I want to maintain that but have a slight issue with the open vent which is why I want to fit a T&P valve in addition to a 3 bar prv.

 

[transam]

Must admit I have not taken alot of notice of solid fuel appliance's over the year's , but if one were to apply a gas boiler scenario , to a sealed system , the boiler would have to have a high limit or over heat stat in order to achieve burner shut down in an over heat situation , this stat would require a manual reset , in solid fuel I don't see how a burner can be shut down ??? completely ??? on an open system a different scenario , would or should be present , uniterupted cold feed to boiler , uniterupted vent to a metal (not plastic) feed tank , with a metal (not plastic ) over flow !! basically fail safe ,.
Not saying you are wrong but something does not sit right with me on this ,????????

 

[Nordio]

in solid fuel I don't see how a burner can be shut down ??? completely ???

Not completely but shut the air supply off and it chokes literally.
I'm confident it will work OK on my retrofit as have now seen a working solid fuel boiler on a sealed system in the UK and lived to tell the tale.

 

[transam]

I don't doubt that it work's , most thing's do , i have seen many non aproved gas boiler's on sealed system's , & they work perfectly o.k , I have seen over heat stat's dissconected the boiler's work o'k , the problem that occur's is the ' What if scenario ' , as I see it if the boiler you speak of is not designed or approved by the manu' to be sealed , than it could present problem's if , a given scenario occured , heat water to high tempreture's under pressure , & it can become very volatile , 1 litre of water can produce 1600 litre's of steam , your average sealed H.W cylinder has potentially the sane explosive power of 3 pound's of T.N.T.

The boiler's you listed as per your website , which appear to be Polish do not appear to be compatablre with a sealed system this seem's to be stated under the heading common error's !!!!?????

 

[stardanny]

It still need to be on a gravity flow and return to cylinder and a heatsink.

The boiler connector is 1 1/2 inch so I don't see how it can be connect to existing system.

Solid fuel boiler on sealed system is high risk and may not be legal.

How big your house? 40kw is a lot.

 

[Nordio]

The boiler's you listed as per your website , which appear to be Polish do not appear to be compatablre with a sealed system this seem's to be stated under the heading common error's !!!!?????

I have not seen that but my polish installation manual seems to indicate the use of a zbiornik wyrownawczy.
Which I assume is an expansion vessel as used on sealed systems.

 

[transam]

The boiler's you listed as per your website , which appear to be Polish do not appear to be compatablre with a sealed system this seem's to be stated under the heading common error's !!!!?????

I have not seen that but my polish installation manual seems to indicate the use of a zbiornik wyrownawczy.
Which I assume is an expansion vessel as used on sealed systems.

On there website , if u translate to English it state's

Most common mistakes 2) Installation of boiler's in a closed system , This is not compatable with existing standard PN-91/B-02413 for solid fuel boiler's , according to the standard required compensatory vessel ?????

Make what u can of that statement ??????