Custom CH Setup - Advice please?

[dangraham]

Hi All,

I am in the process of re-modelling a house and as such all electrics and plumbing will be replaced. I intend to live in this house with my family for the next 10 years. I have some strange needs from my heating system and the plumber I was hoping to help me has let me down so I need to find a new "professional" to help with install and regulations.

The basic primary hot unvented components are as follows.

Log burning stove with back boiler (20Kw)
CHP (15Kw) (Flat plate exchanger)
Immersion Heater if required

120L direct vented copper cylinder
Feed & expansion tank
3x towel radiators
5x small house radiators (first floor)
4 zone UFH system (ground Floor)
450L Buffer tank

This will then need to be connected to a 500L unvented tank with either a coil or flat plate heat exchanger.

What I want from the system is to use the heat output from the CHP that will be available for approx 4 hours per day and use the log burner in the evenings (6pm-12pm) to provide 500L mains pressure HW and approx 600L of CH. The aim is to keep enough in the buffer so I will not need to use gas or electric and will still have warmth in the morning.

I am now in a position to start installing and hopefully have another plumber coming out next week to discuss. Most of the plumbers I have spoken to shy away when I mention buffer or CHP! I would like to work with someone who understands what I am trying to do and design a system that works within the regulations.

As with any project the more information you have the better you understand. Please give me any information on this system or advice you feel is relevant. I would also like to know if heat exchangers would be better than the coil in the 500L tank.

The reason for this system is I have free fire wood from a farm and CHP provides electric and heat from business with very little cost.

thanks, Dan

 

[dcawkwell]

Underfloor and buffer tank should work well.
large volume of water storage of heat etc.

CHP if you have mains gas can't see the point really. I would
rather "invest" the money in solar panels with an air source heat pump.

Log burner if you must but it's a lot of work and hassle
keeping the thing going and lighting it and the mess.

Depends how long you want to be there. Personally I'd just
shove a combi store gas boiler in job done.
If you are leaving in 10 years time any prospective buyer is going
to be turned off by a complicated heating system. They want
it at a turn of a switch.

 

[Norcon]

Ten years will go by in a jiffy.
Save your money and fit something simple.

 

[Athensgasplumbing]

Dear sir,
you are explaining a complex system here. Whilst nothing is impossible but please take my advice: you have stated that a plumber has already let you down and more are shying away....
What does that tell you? problems.When you get this system up and running make sure that you do not lose contact the guy who installs it, because only he will be able to diagnose and remedy any problems.
On a personal note install something simple
All the best, let me know how you get on