Air heater ducting insulation

TheMachMan

TheMachMan

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Anyone ever looked at this?
There seems to a lot of heat losses before the vent outlets around our van. Around the heater there‘s a lot of heat that just soaks into the surroundings at the back of the van under the storage area. And it also radiates into the adjacent bathroom which ends up like a sauna.
Very similar ducting to previous caravans we’ve had that have no insulation on them. Seems a real waste. Must be a more energy efficient way to minimise loses?
 
There is a more expensive blown air ducting that is better insulated as used when pipes pass outside under the floor of a Motorhome, often black. I guess you could lag them too?
 
I have been looking into this as well, even some acoustic ducting and I can’t find anything in 3”. Most is 4” up.
I would be interested what others may come up with.
 
how about this i know its 100mm but does that really ma, maybe run the existing ducting inside it.

easyhvac.co.uk

Aluminium Pre Insulated Flexible Ducts - 100mm, 125mm, 150mm, 200mm, 250mm Dia - All prices inclusive of VAT. - UES Ltd

Flexible reinforced aluminium foil ducting (10m length), wrapped in a 25mm think high-density fibreglass for excellent insulation properties, ideal for supply or extract ventilation. Multi-ply aluminium and polyester laminate construction supported by a high tensile steel wire helix, provides a...
easyhvac.co.uk easyhvac.co.uk

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I covered all our blown air heating ducts in "Armaflex" pipe lagging, made a big difference as the hab space was now getting heated rather the the cupboards and lockers.
This lagging is split so you can cover the ducting in situ rather than having to remove the ducting to cover it.

www.pipelagging.com

Armaflex Self Seal Pipe Insulation Lagging Black Nitrile Foam Class O 2m-76mm-13mm-Wall

Insulation Material: Nitrile Foam Rubber Insulation Thickness: 13mm Suitable for Pipe Size: 76mm Diameter Length: 2 metres Self Seal - Yes
www.pipelagging.com www.pipelagging.com


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Always used armaflex too. Great stuff!
 
Sounds good, I wouldn't mind getting a bit of extra heat to the back of the van but if I insulate the pipes under the floor to achieve it I would end up with a cold floor.
Could be worth doing the smaller 30mm pipes that run up to the outlets that run along the sides of the beds.
Will have to have a look.

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I thought that routing some of the air ducting through lockers/cupboards was to purposefully heat them to prevent cold spots and ultimately condensation/damp?
 
In my case I don’t mind te heat loss as it’s inside the van. I’m more after to dampen the fan noise as I have short runs on 75mm and it can be a nuisance. Somebody on youtube have installed an acoustic ducting that can withstand the heat, with amazing results but can’t find it. I have tried with the intake lengths to balance the flow, a small improvement but not quiet like the acoustic duct. I will give armaflex a go.
 
Agree that some ducting acts as a heat emitter, but around the heater itself there is definitely scope to reduce some of the heat being radiated.
When I took the TV out of the storage compartment it was very warm. That serves no purpose.
 
Alde actually recommend ducting the gas flu in Armaflex to reduce noise. It worked a treat on mine.
 
Perhaps the tv not suitable, but, any solid object it helps with storing heat as thermal mass. The heavier the van the better heat storage. This works both ways, winter and summer.

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The problem is that the more you insulate the ducts the more likely it is that the water pipes in the lockers etc will freeze in very cold weather especially if they are close to the external skin. Uninsulated ducts (and pipes with Alde) are all part of the designed winterising of motorhomes. That is why the ducts and heating pipes are usually close to the water pipes.
 
peterc10 said:
The problem is that the more you insulate the ducts the more likely it is that the water pipes in the lockers etc will freeze in very cold weather especially if they are close to the external skin. Uninsulated ducts (and pipes with Alde) are all part of the designed winterising of motorhomes. That is why the ducts and heating pipes are usually close to the water pipes.
Click to expand...

Ours is a British made motorhome Peter, so none of the above applies. :ROFLMAO:
 
Two on Tour said:
Ours is a British made motorhome Peter, so none of the above applies. :ROFLMAO:
Click to expand...
Well it does still apply a little bit Paul. It means you will no longer be able to use it when it is "a bit nippy", which is, as I understand it, the British standard definition of winterising :ROFLMAO:
 
peterc10 said:
The problem is that the more you insulate the ducts the more likely it is that the water pipes in the lockers etc will freeze in very cold weather especially if they are close to the external skin. Uninsulated ducts (and pipes with Alde) are all part of the designed winterising of motorhomes. That is why the ducts and heating pipes are usually close to the water pipes.
Click to expand...
I found this out when lagged all of mine and used the van, we went out 1 nght and stayed at the pub/hotel we visited as we had trouble getting a taxi back to the van. When we went out we left the heating on low and the forecast was to freeze.
As we hadnt got back till the morning the pipes had froze, not rock solid but enough to not draw.

The lagging I had added had made the garage cupboard where the pipes run too cold, along with the low temp we left the van on. I thnk if we were in the van and having 22 degrees it may have been ok . I have now stripped a section of the lagging from the ducts and also lagged the water pipes.

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Tombola said:
I found this out when lagged all of mine and used the van, we went out 1 nght and stayed at the pub/hotel we visited as we had trouble getting a taxi back to the van. When we went out we left the heating on low and the forecast was to freeze.
As we hadnt got back till the morning the pipes had froze, not rock solid but enough to not draw.

The lagging I had added had made the garage cupboard where the pipes run too cold, along with the low temp we left the van on. I thnk if we were in the van and having 22 degrees it may have been ok . I have now stripped a section of the lagging from the ducts and also lagged the water pipes.
Click to expand...
Depending on how old the motorhome is , whether it is winterised , double floor / single floor etc .
Any pipes that you may have that are "external to the motorhome" ie running under chassis lag as much as possible, the other pipes are normally run in a way to help keep water pipes and possibly your main water tank from freezing , keep damp etc at bay, as well as keeping us warm.

If i lag pipes i would do this in small sections at a time, watch and feel for the effect of your changes.
 
donnod123 said:
Depending on how old the motorhome is , whether it is winterised , double floor / single floor etc .
Any pipes that you may have that are "external to the motorhome" ie running under chassis lag as much as possible, the other pipes are normally run in a way to help keep water pipes and possibly your main water tank from freezing , keep damp etc at bay, as well as keeping us warm.

If i lag pipes i would do this in small sections at a time, watch and feel for the effect of your changes.
Click to expand...
I agree with all the suggestion that people have made but because our pipes run under the floor and can be seen when i lay underneath would it be a disaster waiting to happen,we keep our vehicle in storage so would it be a cost home for mice
 
Bluethunder said:
I agree with all the suggestion that people have made but because our pipes run under the floor and can be seen when i lay underneath would it be a disaster waiting to happen,we keep our vehicle in storage so would it be a cost home for mice
Click to expand...
Double floor vans presumably, like mine, have all the heating pipes between the two floors thus ensuring that in a freeze with the heating on the two water tanks and associated pipes do not freeze also. Lagging them would therefore defeat the object of the design.
 
I lagged mine as others have done in my previous van, made a huge difference to the heating, but after about 8-10 months i had problems with damp, i ended up removing most of the lagging and the damp disappeared
i think it must have been designed with heat loss in mind to keep things dry and ice free.

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What’s the general view of lagging water pipes that are under the chassis exposed to the elements ?
 

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