help with choosing new boiler

[Water Systems]

you want reliabilty avoid a combi,you want something that will work for years without attention avoid a combi.

You obviously have no experience of high class boilers.

 

[Water Systems]

Would everyone pretty much go with that?

you want reliabilty avoid a combi,you want something that will work for years without attention avoid a combi.just my personal opinion out of your selection worc or the vailiant would be the safer bets,have a look at viessman boilers vitodens 200 would be a good one,a bit dearer than the ones you mentioned but more reliable long term

So would you recommend a system boiler with unvented clyinder, so I can get high pressure hot and cold to all taps, plus free up loft of tanks?

It depends on what your DHW requirements are. In a house with one bathroom and one shower over the bath, a high flow combi is more than suitable. Get a top quality one. System boilers and unvented cylinders are overkill (and far more expensive too) with one bathroom.

 

[Water Systems]

Thanks everyone for their thoughts!

OK just had an installer come round to give price on system.

If thinks it best to go for the Rolls Royce of boiler systems: Heatrae Sadia Megaflo!
Reasons
-High Pressure,
-Flow rate, upto Up to 72 litres per minute depending on adequate supply conditions.
-Built in immersion heater, backup hot water if boiler goes down
-Gets rid of Header and expansion tank

He recommend the Valliant ecoTec plus system, not sure exact model.

My only concern is what kind of recovery rates are we looking at, if the clyinder runs out of hot water?

Is there any other thoughts on unvented solution?

Also I have old lead mains coming into the house, but 3 bar pressure from kitchen. Might need to upgrade mains coming to 30mm plastic.

I would tell him to go away nicely. A Glow Worm HXi boiler (made by Vaillant) and an integrated heat bank (thermal store with a plate heat exchanger) . The CH is taken off the store.

Unvented cylinders require an annual service so at today’s prices £2000 over 20 years for just a storing water.

Heat banks give:

- high pressure mains water that is instantly heated.
- No annual service.
- no risk of explosion. Unvented cylinders can do this:
http://www.waterheaterblast.com
- a buffer for CH
- a buffer for the boiler
- TRVs on all rads when a Grundfoss Alpha pump is fitted on the CH.
- High flows than megaflos
- A neutral point for the system
- elimination of boiler cycling.

Cost about the same as a Megaflo but offers so much more and safer and no £100 a year to service it. Megaflo charge £120 for a service.

No contest the Heat Bank wins hands down.
Range Cylinders http://www.range-cylidners.co.uk Flowmaster, and
DPS http://www.heatweb.com make them.

Or go for the ACV HeatMaster. All one unit floor mounted combi at £2,400 complete. But does two bathrooms.

 

[Water Systems]

Thanks everyone for their thoughts!

OK just had an installer come round to give price on system.

If thinks it best to go for the Rolls Royce of boiler systems:
He recommend the Valliant ecoTec plus system, not sure exact model.

Vaillant is not RR quality. Viessman and ECO-Homtec, Etag, Qantum and Atmos are that.

 

[corgiman]

Water systems this is not fair and you have to stop doing it now

This is the second time i have found myself agreeing with you



Thermal stores do deliver a much better flow rate and require little in the way of servicing as water said, but dont forget that they also increase the capacity of the central heating system considerably and require MORE INHIBITER

they amount I have gone to that have sludged up to wotsit in no time cos the original installer just whopped a litre of sentinel in it is untold.

one thing though which may be of relevance to you is that not many jobbing plumbers now a lot about thermal stores (that said not many BG lads do either) so this may effect you when you need a repair made on it when it is out of warrantee

just a thought thats all

PS do not need any special registration to fit a thermal store unlike a unvented hot water storage system, though you'd like to know

 

[kier]

all the boilers you mentioned on page one are fairly decent.
BUT
you need a decent engineer to maintain all of them.
SO
get any of the 3 mentioned,get it fitted properly.
AND
get makers extended warranty and makers to maintain your boiler.

condensers not a diy job as gas valve set up is critical.

 

[novicetodiy]

would tell him to go away nicely. A Glow Worm HXi boiler (made by Vaillant) and an integrated heat bank (thermal store with a plate heat exchanger) . The CH is taken off the store.

Unvented cylinders require an annual service so at today’s prices £2000 over 20 years for just a storing water.

Heat banks give:

- high pressure mains water that is instantly heated.
- No annual service.
- no risk of explosion. Unvented cylinders can do this:
http://www.waterheaterblast.com
- a buffer for CH
- a buffer for the boiler
- TRVs on all rads when a Grundfoss Alpha pump is fitted on the CH.
- High flows than megaflos
- A neutral point for the system
- elimination of boiler cycling.

The Glow Worm sounds like a very go solution to the unvented cylinder. Looked at the spec and the DHW flow rate is 14 l/per min, where as the unvented can, from what I understand, deliver considerable more.
The movie clip has phased me, wouldn't want that to happen in my house. Looks like a scene from Lebanon, Hizbullah RPG coming from the ground

 

[Moz]

Alpha boilers are what I fitted an really liked them ..dead simple an good honest recommend

 

[Moz]

kier
"condensers not a diy job as gas valve set up is critical....."

an not forgetting the extra regs on this product being a hot water time bomb if not fitted right /discharge an safty etc, remember that woman who was scolded to death from hers in RGI mag

 

[Water Systems]

would tell him to go away nicely. A Glow Worm HXi boiler (made by Vaillant) and an integrated heat bank (thermal store with a plate heat exchanger) . The CH is taken off the store.

Unvented cylinders require an annual service so at today’s prices £2000 over 20 years for just a storing water.

Heat banks give:

- high pressure mains water that is instantly heated.
- No annual service.
- no risk of explosion. Unvented cylinders can do this:
http://www.waterheaterblast.com
- a buffer for CH
- a buffer for the boiler
- TRVs on all rads when a Grundfoss Alpha pump is fitted on the CH.
- High flows than megaflos
- A neutral point for the system
- elimination of boiler cycling.

The Glow Worm sounds like a very go solution to the unvented cylinder. Looked at the spec and the DHW flow rate is 14 l/per min, where as the unvented can, from what I understand, deliver considerable more.
The movie clip has phased me, wouldn't want that to happen in my house. Looks like a scene from Lebanon, Hizbullah RPG coming from the ground

Yep one can take down the side of your house and £100 a year to have serviced. Go integrated heat bank - DHW and CH heated by a Glow Worm "heating" boiler.

 

[Water Systems]

Water systems this is not fair and you have to stop doing it now

This is the second time i have found myself agreeing with you

This is encouraging. It shows progress.

Thermal stores do deliver a much better flow rate and require little in the way of servicing as water said, but dont forget that they also increase the capacity of the central heating system considerably and require MORE INHIBITER

they amount I have gone to that have sludged up to wotsit in no time cos the original installer just whopped a litre of sentinel in it is untold.

That is ignorance not the product itself.

You can eliminate that by design. Have the boiler heat the cylinder by a quick recovery coil - many Gledhills do this. Have the CH taekne off the store via a coil too - the boiler and CH circuits can be sealed by using a system boiler. The two circuits are joined by one 8mm, 10mm, 12mm or, 15mm, pipe. Have an anti convection loop in this pipe to avoid the boiler heating the CH circuit (this you don't want). The sealed system's pressure vessel and pressure relief controls operates on both circuits.

The store is vented with the same water only ever staying in teh cyodiner. it os just heatend and cooled (the storage mediun, the thermal store). It doesn't even need inhibitor in the cylinder as this water only stays in the cylinder, although an initial 1 litre can does no harm. 1 litre can in the boier/CH circuits.

Or, have just the one quick recovery coil in the cylidner and have the boiler use it to heat the store (pumping heat into the store ASAP with no boiler cycling) and using zone valves have it reverse it operation (pumping heat out of the store) heating the CH system.

So you can use the same cylinder coil to heat the store and the same to extract heat from the store to the CH circuit.

one thing though which may be of relevance to you is that not many jobbing plumbers now a lot about thermal stores (that said not many BG lads do either) so this may effect you when you need a repair made on it when it is out of warrantee

just a thought thats all

They are simple enough for anyone to figure out the operation. In fact they are very simple indeed.

PS do not need any special registration to fit a thermal store unlike a unvented hot water storage system, though you'd like to know

 

[corgiman]

Good points all

As to my last bit about repairing them, I find therm simple, you find them simple but i have followed many many many op's who dont and give every excuse under the sun just to get the hell out of it. You will find someone to sort it but you may have to go through a few before you find them

And I feel this should be a consideration when selecting any type of system.

 

[Water Systems]

Good points all

As to my last bit about repairing them, I find therm simple, you find them simple but i have followed many many many op's who dont and give every excuse under the sun just to get the hell out of it. You will find someone to sort it but you may have to go through a few before you find them

It doesn't give me confidence in abilities of the average British tradesman

 

[corgiman]

Why not

do you seriously expect every bloke out there to know about everything?????? we cant all be Agile (amen )

Why even doctors practice water systems

cut everyone a break for the love of god, we are all on a perpetual learning curve.

Sheesh, bet even you had to do something for the first time once.

Up untill recent (thanks to gledhill) thermal stores were something of a rarity, so why would anyone spend their hard earned training up on something they would have seen once in a blue moon.

That said they would be well advised to get up to speed very quickly now

 

[Water Systems]

Why not

do you seriously expect every bloke out there to know about everything?????? we cant all be Agile (amen )

If a plumber of heating man can't understand a thermal store he should get a job on the milk.

Up untill recent (thanks to gledhill) thermal stores were something of a rarity, so why would anyone spend their hard earned training up on something they would have seen once in a blue moon.

That said they would be well advised to get up to speed very quickly now

In the modern sense Gledhill developed them with B Gas in the 80s. There are countless makers of them. Whole estates are full of them.

I know of one instance where the Range Flowmax store had a failed blending valve (£35 to buy). The local idiot plumber came along and said get rid and installed a tank and cylinder with a power shower pump. I would have taken the sod to court for that.

The ignornace that surrounds thermal stores/heat banks is phemominal. You only have to read the tripe so-called professionals say about them here. One was onj about them never being in a position to make a condensing boiler condense. They are now becoming the norm in Germany - they call them buffer stores. Buffer storage is becoming big in Germany - they will fit a small CH buffer in a system to eliminate boiler cycling, reduce boiler size and have TRVs on all rads.