How is this heat exchanger plumbed internally?

[RobinAbbott]

Untitled

• RobinAbbott
• 9 Oct 2011
• 1

Hi all - I have a complex dual fuel system which I am trying to figure out to understand one or two problems with it.

Any way I have included a pic of the first confusion which is the heat exchanger. The box sits under the tank. There are two pipes (in and out) on each side of the exchanger, 8 in total. The two at the front go to the hot water tank coil as can be seen in the pic. Two at the left to the central heating pump, two at the right to the woodburner, and two at the back to the boiler.

So - I cannot find this exchanger anywhere on the web or anything which looks anything like it. Anyone tell me anything about it ? Is there a link between any of the pipes? Is the box itself full of water? Is it insulated internally ? Grateful for any info at all.

 

[twgas]

I think this site may be able to help explain your "device".
http://www.dunsleyheat.co.uk/neutralizerpics.htm
what actual problems do you have?

 

[RobinAbbott]

OK, got it, so this box which has puzzled me so much turns out to be an empty metal box with 8 pipes connected in to it and full of water !

And worst of all it costs ~£250 !

 

[Dan Robinson]

Depends how you look at it.

 

[bell824]

yep really dependson how you look at it!!
from what i see this looks like a hot water cylinder and not many cost £250 these days!!!

 

[RobinAbbott]

Well, the item of interest is the silver box under the cylinder not the cylinder itself, and I still think it's expensive ! Thanks to my first reply I now know what it is.

It is a "neutralizer" and effectively a water tank with 8 pipes connected in 4 pairs. Two pairs connected to heat sources (the boiler and the wood burner), one pair to the hot water cylinder (gravity fed) and one pair to the central heating circuit (driven by a pump). For anyone else who wants to find out more then the first reply has a very useful link.

 

[Corgigrouch]

The neutralizer is a bit of a niche product that solves the problem of connecting multiple heat sources. I know of no other manufacturer who makes such a product. What you have to calculate is how much would it cost for you to manufacture your own neutralizer including travel time to and from the fabricator. Unless you are a a sheet metal fabricator, then the costs do escalate just to make a watertight metal box.

If you knew the manufacturing cost of an iPhone would you feel that the retail cost was expensive?

Dunsley is a British manufacturing company and so keeps British skilled workers in a job and off the dole queue.

 

[DeltaT2]

Well, the item of interest is the silver box under the cylinder not the cylinder itself, and I still think it's expensive ! Thanks to my first reply I now know what it is.

It is a "neutralizer" and effectively a water tank with 8 pipes connected in 4 pairs. Two pairs connected to heat sources (the boiler and the wood burner), one pair to the hot water cylinder (gravity fed) and one pair to the central heating circuit (driven by a pump). For anyone else who wants to find out more then the first reply has a very useful link.

I can see you're missing a strap on thermostat on your system Robin, there should be one on the neutralizer. What other problems are you having with it?

 

[RobinAbbott]

I did another post concerning the control box which is an electronic thermostat - you can see the two heat sensors in the photo above.

What do you mean by a "strap on thermostat"?

The issue's are :

1) There are two pumps, a central heating one (easy), and a boiler pump. I think the boiler pump is supposed to run when the boiler is on to circulate hot water into the neutralizer. However I found that it is noisy and not necessary - when the heating is off, the boiler works fine on a gravity feed to warm the hot water with the pump off, so I wired the boiler pump to only come on with the heating.

2) I think the control box is faulty as it turns on the central heating pump all the time. The control box is connected to the room stat so that the central heating comes on only when its too cold. However then the central heating pump runs continuiously regardless of hot water so it takes an age to get hot radiators and hot water.

 

[DeltaT2]

All the wiring details are shown in the link above mate, download the installation instructions.
HTH