Magic Box - Snake Oil?

[balbecdaze]

Got a sales call pushing this yesterday. I've sent them an email:

"Thank you for your email, XXXXXX.

I found the promotional literature and your and the manufacturer's website very intriguing. I would be interested to add this product to our portfolio but I wonder if you could clear up two issues for me:


1) Somewhere in the promotional literature I read that: "When a radiator is heated completely from top to bottom, the radiator gives off a radiant heat.". This seems like psychobabble and completely puts me off, if there is any physics behind this statement I would love to know it. It is my understanding that the significant part of heating from a radiator, as it permeates through a room, is due to convection. I fail to see how a radiator being at a uniform(ish) temperature could change this.


2) Also somewhere I read that Trinity College, Dublin had evaluated the product, I would need to see a copy of their report.


I await your response with interest."

If I get a response I will update, it seems to be a mixer for Central Heating Systems.

Now, my understanding of Central Heating is that cold water goes in, get heated and passed through the radiators and then heated up again. So my understanding is pretty basic and I just don't get this system.

Does anyone with any real knowledge have anything to enlighten me? Especially this nonsense: "Condensing boilers will only condense efficiently when the water returning back to the boiler is below 55°C. Unfortunately with the current systems most boilers only condense at start up stage as the return temperature exceeds 55°C. Therefore most households lose out on the benefits that condensing boilers provide. When the Magic Heating Box is installed, the return temperature stays below 55°C keeping your modern condensing boiler in condensing mode. The Magic Heating Box is the only product available on the market today that can keep a boiler in condensing mode without having to sacrifice your comfort levels."

Surely if the return temperature is higher, the boiler has less work to do?

Basically, is this "Magic Box" a good thing or not?

 

[Gavin A]

Does anyone with any real knowledge have anything to enlighten me? Especially this nonsense: "Condensing boilers will only condense efficiently when the water returning back to the boiler is below 55°C. Unfortunately with the current systems most boilers only condense at start up stage as the return temperature exceeds 55°C. Therefore most households lose out on the benefits that condensing boilers provide. When the Magic Heating Box is installed, the return temperature stays below 55°C keeping your modern condensing boiler in condensing mode. The Magic Heating Box is the only product available on the market today that can keep a boiler in condensing mode without having to sacrifice your comfort levels."

Surely if the return temperature is higher, the boiler has less work to do?

Basically, is this "Magic Box" a good thing or not?

well that bit's correct - condensing gas boilers require a return temp of 55 or below to operate in condensing mode, and lower is better. They don;t need to do more work as long as the heating system is designed to operate at lower temps, which most are IME as long as there has been some work done to thermally upgrade the building eg double glazing windows, loft insulation, cavity wall insulation etc since the rads were installed.

re the other bit... well if the entire rad is heated top to bottom then there's more surface area to emit radiant heat from, so I guess that kinda works. I think though that it mostly works by removing air and dirt from the system fluid, which will improve efficiency of heat transfer, and I suppose avoid air locks, as well as operating as a boiler return thermostatic valve to keep the boiler return temp at optimum... something like that.

I'd expect it would have a benefit, but probably in the 5-10% range at an educated guess. Personally, having had a bit of a nightmare with retrofitting TRVs to an old heating system (and power flushing, new controls etc) and realised how much of a can of worms you can end up opening up by messing with old systems, I've no interest in this unit as you'll not be able to charge enough to cover the likely costs of the call backs and fixing the can of worms you've opened up.

If I were installing a new system from scratch though I might consider it, but that ain't our game.

 

[solarsavings]

From what I've seen of the magic box heating system it appears no more than a low loss header with weather compensation controls. The llh will prevent the boiler cycling and should lower fuel usage as a result.....................................................................................................how much will save????????????????? at what cost?

 

[Gavin A]

ah, it's a low loss header... wish they'd just say that instead of babbling

 

[Gavin A]

so erm how does it increase the flow rate through the rads by 70%?

 

[solarsavings]

There's more money for shiny suits in babbling.

 

[solarsavings]

so erm how does it increase the flow rate through the rads by 70%?

Bigger pump, larger pipe size? One of many questions that should be asked.

 

[Earthstore]

Now if it is the Black Magic Box my girlfriend would love them...

 

[balbecdaze]

Thanks Gavin A, I get the 55 degree bit now. I'm going to tape a thermometer to my pipes!

 

[balbecdaze]

Ok, I got an update. It does sound like a low loss header (I had to google low loss header though so I could be wrong), they put in a new pump and the higher flow rate plus the air valve in the Magic Box decreases the temperature the boiler has to heat the water to.

They also fit new (differently designed?) TRV's to all the rads and a new central thermostat. Oh, and open up all the return valves on the radiators.

The convection/radiation bit seems to be that because the radiator is now at a nearly uniform temperature, there is little convection inside the radiator. They aren't making any claims about what the heat does when it gets into the room.

I have to give the company credit for a prompt, polite and thorough response.

Personally it's too far out of my skills set for me to recommend to customers, I'd have to know how efficiently their present central heating was working amongst other things. If I hadn't gone the wood burner route in my own home I wouldn't be averse to getting a quote though.