Viessmann WB1B 13kw

[desktop987456]

Hi,
Attached please find pictures of a boiler that I intend to buy for my home; a 13kw (used) viessmann regular boiler with pump and diverter valve (in the picture). What else do I require for installation and spares that I can get from London before it is shipped to me. I am not in UK and this will be installed in my home town in Pakistan so it will be sent to me from London. The smallest boiler available here is 24kw!

I intend to use it for Central heating only, my current boiler is non condensing type so this would be a huge improvement for me.
Thanks

 

[desktop987456]

Anyone? What else do I require for installation and spares that I can get from London before it is shipped to me. Thanks.

 

[dilalio]

 

[desktop987456]

I understand.
Current boiler - Non Condensing
System - OV, CH only, no DHW
Feeder Tank - Yes
Expansion vessel - No
Pressure Relief Valve - Yes
Radiators - 10.
No TRVs or thermostat
No fancy system.
Don't want to spend >300 on boiler, its a risk but I couldn't get a smaller boiler 11-13 kw in my home country. This is what I could afford to minimise gas usage.

 

[roguetrader]

Hi,
Attached please find pictures of a boiler that I intend to buy for my home; a 13kw (used) viessmann regular boiler with pump and diverter valve (in the picture). What else do I require for installation and spares that I can get from London before it is shipped to me. I am not in UK and this will be installed in my home town in Pakistan so it will be sent to me from London. The smallest boiler available here is 24kw!

I intend to use it for Central heating only, my current boiler is non condensing type so this would be a huge improvement for me.
Thanks

Out of interest desktop987456,
Are there registered gas engineers in Pakistan?
And a building regulations system?

 

[desktop987456]

Winters here don't last as long as in UK and very few people have CH systems. There are lot of HVAC technicians in this part of the world but not many heat engineers. I couldn't find a 15kw system here that is why I am getting one for my needs from UK after doing heat loss calculation of my property.
No building regulations enforced here for CH or insulation of property.

 

[dilalio]

Winters here don't last as long as in UK and very few people have CH systems. There are lot of HVAC technicians in this part of the world but not many heat engineers. I couldn't find a 15kw system here that is why I am getting one for my needs from UK after doing heat loss calculation of my property.
No building regulations enforced here for CH or insulation of property.

Are you on a gas main?
Or tanks of lpg?
Is the gas the same as would be used in boilers in the UK?
Would a product designed and used in the UK be happy running on Pakistani gas?
There's a lot more to using minimum KW output boiler to conserve fuel.
You should be looking at load/weather compensation and turndown ratio for efficient modulation.

Viessmann are good for low modulation but depends on model and age.

You mention nothing fancy, but your boiler will operate much more efficiently with the right controls and TRVs on rads.

 

[dilalio]

Pressure Relief Valve - Yes

Why?

 

[desktop987456]

Why?

There is a PRV in my existing system.

 

[dilalio]

There is a PRV in my existing system.

But you said its open vent! Why does it need a pressure relief valve?

 

[desktop987456]

Are you on a gas main?
Or tanks of lpg?
Is the gas the same as would be used in boilers in the UK?
Would a product designed and used in the UK be happy running on Pakistani gas?
There's a lot more to using minimum KW output boiler to conserve fuel.
You should be looking at load/weather compensation and turndown ratio for efficient modulation.

Viessmann are good for low modulation but depends on model and age.

You mention nothing fancy, but your boiler will operate much more efficiently with the right controls and TRVs on rads.

Natural Gas - yes. GCV value around 1050 btu.

I have read a lot about turn down ratio that is why I have chosen viessmann. My plan is to upgrade the boiler first, it will be a huge improvement to my existing boiler. If for some reason the boiler doesn't like NG here then my other plan is to convert it onto LPG.
I live in a hard water area so limescale build up could be an issue.

The only boiler I could get here was 24kw and that too for ~1000GBP! This is going to be 1/3rd of a price delivered here so I am going to take a gamble and if it turns out Ok then I'll upgrade controls.

My inclination for this purchase is 10-20% saving from non condensing to condensing world. My target is to bring gas consumption down from 19000 kwh/annum to 15000kwh in FY24. With DHW being diverted to electric (since I have 10.8kw solar) and efficiency gains in boiler upgrade I should be able to bring my usage below my target. This winter will be moment of truth for this project, if it didn't work the way it should then I can always put the old boiler back in winters.

The post was to get expert views such as yourself if I need to get anything else for installation here. I have access to couple of good technicians who would do the job for me. The main thing is to get the right sized equipment. My two boilers (a 26kw and 16kw both non condesing )will also have some salvage value so economics for this upgrage looks right to me.

How big expansion vessel would be required for this; 8 litres? Thanks in advance.

 

[desktop987456]

I inherited the system and I have brought the usage down over the 3 year period.
2nd HW storage tank made redundant in 2021, last year decommissioned the other boiler and extend the pipework to 1 boiler operation for the whole house. I have already fixed gas leaks in internal pipework (two kitchens in two floors) this week and it is going to bring gas usage down to 5%. The rest I am counting on boiler upgrade.

 

[dilalio]

Open vent or sealed?
You've been alluding to both!

 

[ianmcd]

edit

 

[desktop987456]

Open vent or sealed?
You've been alluding to both!

Open vent please.