Finned pipe radiators

[clankypipes]

Hi,

Hoping for some advice. I'd like to install the 'finrad' type of radiator in a particular place in my house, and they seem to vary hugely in price. Aluminium ones like this seem to be quite cheap - ALDE FINRAD CONVECTOR ALUMINIUM 400MM - Midland Chandlers - Canal and Narrow Boat Equipment

I know they're sold for narrowboats and the like, but is there any reason why I couldn't hook one of those up in place of a normal domestic radiator? Is there any problem with using aluminium pipes? I currently use the Corgi corrosion inhibitor that Toolstation sell. And mine is a pressurised system running off a combi boiler.

Thanks in advance!

 

[Chuck]

Is there any problem with using aluminium pipes?

There is a potential issue with 'electrolytic corrosion', which can be overcome with care.

How To: Control Corrosion in Central Heating Systems | Sentinel

Why Buy Aluminium Radiators?

The problem with systems that need to be treated 'with care' is that many owners and some plumbers are not careful...

 

[ShaunCorbs]

They don’t kick out enough heat / they need to be long

 

[chris watkins]

Search "Gilled Tube" for a better solution

 

[clankypipes]

Thanks very much for the advice! Sounds like aluminium is fine as long as an inhibitor has been used.

Any advice on the best way to join those 22mm aluminium tubes to the rest of the system? I've used compression fittings almost everywhere else, but I wonder if aluminium might be too soft...?

 

[chris watkins]

They are listing a 22mm push fit coupling along side the convectors so i would guess you use them to make the connections on each end, not compression. Coming out of the other side I would install a short of copper with a 22 to 15mm reducer then a straight TRV (possible with remote sensor) to the flow side & a straight patten locksheild rad valve or gate valve on the return, this will allow the water flow to be adjusted right down as required.
Please remember wherever they are install there must be a minimum of 100mm clear air space below & no boxing / shelfs above, you should also allow access as they will need to be carefully cleaned every year for them to give the stated outputs.

 

[clankypipes]

Hi Chris

Thanks so much for all that advice - really appreciate it.

Can I ask why it wouldn't be OK to put them in an enclosure though? That was very much where I was heading. Are they not normally installed behind grilles or boxed in?

My plan was to install 12v fans in a bank behind a pair of those radiators (installed in series) hooked up to a simple thermostat to activate the fans once the temperature in the enclosure gets above a certain level. It would be vented on three sides with mesh or grilles or some such thing, but only minimal venting above. Probably sounds rather complicated, but it's for a space where there isn't really room for a standard radiator, and where I want the heat to go out rather than up, if you see what I mean.

 

[chris watkins]

Simply the air flow if required to carry the heat way if you are using natural convection then it need to be as unrestricted as possible.
If you go for a forced using a fan, someone beat you to it I would suggest trying to use one of these as there are other issues with air flow when heating is not on.
https://www.myson.co.uk/static_files/my/media/downloads/01. Kickspace.pdf

 

[Chuck]

Any advice on the best way to join those 22mm aluminium tubes to the rest of the system?

What does the radiator manufacturer recommend?

In theory, at least, a wet joint between Al and Cu is going to suffer from quite severe electrolytic corrosion. Inhibitors correctly used will slow this process but I'd still make sure that any such joint was not hidden away so that when it starts to leak it will be noticed and easily repaired/replaced.

I'm at the paranoid end of the spectrum when it comes to this sort of thing because I like plumbing to last 50+ years not just five.

 

[clankypipes]

Thanks all for the advice. Took it to heart and ordered a copper pipe based version instead, here: Gunning Finned Tube Heating Elements/Exchangers

Bit more expensive, but removes any doubts around corrosion.

Swapped a few emails with them, and they were really helpful actually. Quite looking forward to getting it set up to be honest - be interesting to see how well it works.

And take the point re the plinth heater idea, it's just that even secondhand they seem out of my budget, whereas I can do this for comfortably under £100 and it'll all be brand new. Plus it'll be fun figuring it all out!

 

[chris watkins]

Thanks for the link, I hadn't come across them before.
Let us know how it all works.