New Boiler & Vented Heat Bank Location

[megawatt]

Firstly ... Happy New Year to you all.

I'm considering having my current Worcester Highflow 3.5 Combi replaced (Feeding DHW to 4 bed house with 2 bathrooms and Sealed System CH with 13 rads) and quite like the look of DPS's Pandora vented heat bank fed by either a conventional or system boiler to give full flow hot water ... I like to do most things myself (other than gas) so the Pandora setup presses all my buttons

I have quite a few options for locations of the new kit but need to make some decisions now as I'm about to re-fit the utility room which is where the current boiler lives.

I have a couple of questions ...

1. Is it permissible to house the boiler and heatbank in the garage (ours is quite large) rather than the utility room i.e. Are there any regs or issues preventing doing this?

2. I quite like the idea of using a conventional boiler (say the Worcester Greenstar 30CDi as an example) rather than a system equivalent (Greenstar 30CDI System HE) as all of the additional components can be supplied fitted to the Pandora and are then far easier to maintain/replace than when they are fitted inside the boiler case. Are these boilers interchangeable in this way and only differ in the fitting of the additional system components ... Expansion tank, PRV, PUMP etc etc or am I missing something?

Thanks in advance

Andy

 

[Water Systems]

Firstly ... Happy New Year to you all.

I'm considering having my current Worcester Highflow 3.5 Combi replaced (Feeding DHW to 4 bed house with 2 bathrooms and Sealed System CH with 13 rads)

What is wrong with it?

and quite like the look of DPS's Pandora vented heat bank fed by either a conventional or system boiler to give full flow hot water

The Pandora, as I know it and could have changed, is heated via quick recovery coil, so a system boiler is best here.

... I like to do most things myself (other than gas) so the Pandora setup presses all my buttons

I have quite a few options for locations of the new kit but need to make some decisions now as I'm about to re-fit the utility room which is where the current boiler lives.

I have a couple of questions ...

1. Is it permissible to house the boiler and heatbank in the garage (ours is quite large) rather than the utility room i.e. Are there any regs or issues preventing doing this?

No problem.

2. I quite like the idea of using a conventional boiler (say the Worcester Greenstar 30CDi as an example) rather than a system equivalent (Greenstar 30CDI System HE) as all of the additional components can be supplied fitted to the Pandora and are then far easier to maintain/replace than when they are fitted inside the boiler case.

As I said, I understand that the Pandora is heated via a large internal coil so a normal system boiler is the best option here.

Are these boilers interchangeable in this way and only differ in the fitting of the additional system components ... Expansion tank, PRV, PUMP etc etc or am I missing something?

Thanks in advance

Andy

The best is have the CH off the heat bank and have a Grundfos Alpha pump on the CH circuit and TRVs all around. Then fit a Magnaclean filter on the CH return to the cylinder. Not sure if this is an option on the Pandora. The DHW only Pandora is a brilliant alternative to an unvented cylinder: safe, no overflow, no expensive annual service and higher mains pressures can be used.

 

[ChrisR]

Basics come frst - what's your current mains pressure and flow, and what do you need?

 

[Bigburn]

megawatt

Are you a spark ?? (not that its anything to do with your post but your name makes me think this)

 

[Water Systems]

Basics come frst - what's your current mains pressure and flow, and what do you need?

He already has a mains pressure system supplying two bathrooms.

 

[ChrisR]

He already has a mains pressure system supplying two bathrooms.

I know.
My question is valid, and stands.
As you claim to be a hyper-intelligent megabeing I really shouldn't need to explaiin why.

 

[megawatt]

Wow guys, thanks for the quick response.

Bigburn: Amongst other things nowadays

ChrisR I could measure the pressure and flow of the current system (and will do before making any final commitment) but I'm sure that they will be fine for the Pandora as both are sufficient at both bath hot taps opened simultaneously ... problem is the combo can't heat the water at the max pressure/flow.

Water Systems Apart from the time it takes to fill the bath the boiler is starting to have issues due to it's age (over 15 years old) ... Kettling and related problems etc. I would like a new installation prior to fitting the new utility room as I will need to do some extensive re-piping if I move everything to the garage and one which will offer piping hot water at full flow.

Best wishes

Andy

 

[megawatt]

I forgot to add ... If you wish to see my proposed Pandora config ...

http://www.heatweb.com/techtips/panex.html

Click on "Enter Design Code" and enter CPC-210-AKMCB

With this configuration I'm not sure why I need the system boiler rather than a simple conventional one?

 

[Water Systems]

I forgot to add ... If you wish to see my proposed Pandora config ...

http://www.heatweb.com/techtips/panex.html

Click on "Enter Design Code" and enter CPC-210-AKMCB

With this configuration I'm not sure why I need the system boiler rather than a simple conventional one?

You NEED a system boiler with this setup. The Pandora is heated via a large coil not direct. There is no F&E tank with this setup. It has an integral S plan system using zone valves. The CH is heated directly from the boiler not the cylinder.

What you need is a DPS GXV heat bank. Look it up. This can incorporate a heating (non-system) boiler and heat the CH directly. The Range Flowmax is similar, so price this up as well - Probably cheaper.

 

[megawatt]

Water Systems: Whilst I don't usually question the experts, are you sure about this?

My current CH system is pressurised and it is my understanding that the GXV system can only be used on OV CH systems?

Maybe I didn't ask the question very well ...

No problem using the system variant of the 30cdi though as it will work out cheaper and not have the additional components on the Pandora (other than the zone valves).

I've asked the same question to the DPS guys (don't know why I didn't think of it earlier) to see what they reckon.

Thanks for the help.

Andy

 

[Water Systems]

Water Systems: Whilst I don't usually question the experts, are you sure about this?

My current CH system is pressurised and it is my understanding that the GXV system can only be used on OV CH systems?

The GXV yes, not the Pandora. The Pandora can have an open vented boiler but you need a separate F&E tank. Best have a system boiler and a pressurised system on the Pandora

No problem using the system variant of the 30cdi though as it will work out cheaper and not have the additional components on the Pandora (other than the zone valves).

The Pandora is a DHW only heat bank. The S plan valves are bolted on for convenience only. An integrated heat bank (CH & DHW) has the CH and DHW off the same cylinder, heatede by the stored water. The Pandora has the CH heated directly from the boiler. An integrated system gives superior buffering of the boiler and CH circuits.

 

[Bigburn]

megawatt wrote

My current CH system is pressurised and it is my understanding that the GXV system can only be used on OV CH systems?

The GX Heat Bank for Sealed Systems

To provide greater flexibility in design and installation, we developed along-side the GXV, the GX Heat Bank for a sealed systems.

Where the installation will not allow the fitting of an F&E tank, the GX overcomes the problem by the use of a built in expansion vessel. The entire GX and heating system is pressurised, and no separate F&E tank is required. The GX is fitted with all the usual sealed system controls including:

Expansion Vessel
Pressure Relief Valve
Pressure Gauge
Overheat Thermostat
Filling Loop

It states the above on the DPS website .
Hope this helps.

 

[ChrisR]

WS seems to be confusing System boilers with open systems.
There's nothing whatsoever stopping you using a non-system boiler with an external pressure vessel and pump.
"System boiler" is undefined really - some of them have/had diverter valves in as well. More often than not it's a combi with bits missing...

 

[megawatt]

I'm with you now WS

Yes, the Pandora is just for the HW and the CH will be supplied direct from the boiler.

DPS can provide a lower sealed circuit on the Pandora for CH (another plated heat exchanger and pump) but it seems a bit of an overkill (and more £'s) so I may as well let the boiler get on with the CH, got to get some benefit from the Condensing after all

I don't plan on having more than 1 CH zone either so could use Y plan also but everyone keeps telling me S plan is better as it avoids the use of mid-position valves ... Any views on this?

There's a couple of problems with the GX systems ... They're pressurised so they're not DIY'able (I believe) and having primary water flowing through the store surely makes them more prone to corrosion etc. The thing I like about the Pandora is that the store water is totally self-contained ... And filled with a hose through a hole ... By eye

ChrisR: Thanks for that, it's what I had originally hoped as all the system bits and pieces look cramped in the boiler yet nice and easy to work on when fitted to the Pandora. It's interesting though that Worcester state that the 30cdi Conventional is for a small/medium house but the 30cdi System is for a medium/large house ... Yet the figures for the boilers look remarkably identical as do the internals ... Hardly any cost difference between the two makes the system variant it a little more cost effective, though I still fancy having all the components easy to replace even if a little more expensive up-front

Andy

 

[Water Systems]

WS seems to be confusing System boilers with open systems.

I am not. In the context of what he is talking about, no.

"System boiler" is undefined really - some of them have/had diverter valves in as well. More often than not it's a combi with bits missing...

A system boiler is well defined. The minimum is :

- pump
- pressure vessel
- pressure guage

Many have more.

The idea is to just connect it up and not worry about F&E tanks and pumps. The only external controls were zone valves. They were intoduced to the UK in the 1980s, after the combi. In 1980 the UK had no system boilers for sale, locally made or imported.

I believe either Chaff or Vaillant brought the first out in the early 1960s. The UK was way behind making cast-iron crap - we still are way behind, especially in implemetation stil using cold tanks and cylinders.

Chaff introduced the combi in the 1950s.