Airflow through 3.5 tonne

[SEL]

I picked up my lorry in torrential rain, drove it home down the motorway cursing lorries - and then I don't think we've had more than a shower since.

Baby cob is sweating up in it a lot - to the extent where he spends 24 hours after a trip looking nicely slimline due to dehydration. I didn't take him out last weekend because I don't function at 30 degrees and we've got family stuff this weekend but I need to find out if its him just struggling or if the air isn't moving in the van properly. I can see him on camera and when we went to the "I'm going to show the in hand judges how athletic I am" show he really looked like he was struggling coming home. I was putting my foot down on the straight bits to try and see if that would get air through, but he was head to toe drenched by the time we got back.

He's young so once he's hosed off and turned out he really couldn't care less thankfully but he was sticky getting back on the box and he's been a walk straight on type so if there is a problem I need to sort it.

Facing towards the rear so bum behind the driver. Two little windows just beyond his head and a roof pop up vent thing. All open as wide as they can be. I'm pretty sure that's the normal design in a 3.5 tonne but if anyone has any advice or has improved ventilation let me know.

OH is wondering if we could fix a fan to the battery somehow.

Thank you

 

[shortstuff99]

I have a ceiling fan in mine, but you also have to put the air vent at an angle and then the hot air is pulled out via vacuum

 

[Squeak]

I *think* there should be two windows by his head and then a smaller higher one by his quarters and in an ideal world a roof vent too.

Kevin Parker Horseboxes did a great post on FB about it a while ago, I'll go and see if I can find it.

 

[Squeak]

Unfortunately I could not work out how to link to the FB post this time so I've copied and pasted for Kevin Parkers FaceBook post and all credit to them because it's a really informative and helpful post:

To pre-empt the forecast for much warmer weather I have added some information on designing horseboxes to cope with heat and a few pointers for horsebox ventilation in hot weather.

Designing primarily around horse safety and comfort, we dedicated many hours to the issues of heat build-up. There is without question plenty of research already out there on the effects of prolonged exposure at high temperatures and how it causes heat stress, heat stroke, dehydration, muscle spasms and colic. These are all avoidable issues if addressed as part of the overall ventilation design.

Heat and colour

From previous research and development, roof colour has to be white to reflect heat. Dark colours absorb heat, so avoiding a dark finsh is essential.

Head room

I cannot understate the importance of head room as part of any good ventilation strategy. It is a crucial aspect of any horsebox design. As heat rises, the hottest part of the horse area is always going to be nearest the ceiling. For our part we use 8’ up to 8’ 6” headroom. Not only does this make horseboxes suitable for the largest of horses, it keeps the hottest air high up above the horses head height, where ventilation systems can easily remove it.

Windows and air flow

Glass and especially colour play an important part again and tinted glass is preferable. It reduces direct sunlight that adds extra heat to the horse area, so tinted glass is good as long as it remains clear enough for the horses to see out. Widows are basically the starting place for good air flow and heat removal. Window size plays an important part in the cooling effect of air drawn over the horses. A good design will see one large horse window for each horses head and smaller higher windows at the tail. This window size difference is crucial as it allows air flowing past a moving horsebox to cause a greater vacuum on the larger windows than the smaller ones. This vacuum effect draws air into the horsebox through the small windows, across the horses and out of the larger head windows. However, it is worth noting that if both windows were the same size, air pressure would be equal both sides of the horsebox and little to no air would move inside the horse area. This effect is mostly for a moving horsebox with all the windows open. For a stationary horsebox very little air moves across the horses apart from that caused by wind. It is also noteworthy that for hot or stale air to leave the horse area, fresh clean air must have a way in. For example, closed tail end windows would stop air flowing in and being drawn over the horses, so no cooling effect would be present.

Roof vents and air flow

Let’s start with a hot horse area and a stationary horsebox. The hottest air is at the ceiling and cooler air low down. Opening a roof vent fully will allow hot air to flow up and out causing cooler air to flow in through the windows. A clever trick here and one we use in our own horsebox design maximises this effect by allowing much cooler air to flow in at floor height.

For a moving horsebox with a hot horse area things get more complicated still. Opening the roof vent and windows fully will remove some hot air, however, there is a way to move much more hot air out by tilting the vent. Actually opening fully the rear most part of the vent and closing the cab end of the vent fully will cause a considerable vacuum effect as air passes over the horsebox roof and tilted vent. At speed this vacuum effect will be considerable and as long as the windows are open the cooling effect will also be considerably increased, even removing more hot air more than an extraction fan!

Intake and extraction fans

These can be even more complicated depending on the size of horse area and the amount fitted. For a moving horsebox fans actually remove less air than a tilted roof vent. Where fans really shine, is parked or stationary traffic and even ferry or tunnel crossings where little air flow is possible. For small horseboxes with open windows probably one extraction fan is all that is necessary. For larger horseboxes intake and extraction fans are fitted and this negates the need for open windows. Remember fans use considerable power and if the engine is not running they can soon flatten batteries.

Air conditioning

This is the most controllable option and one we use for our largest HGV horseboxes. These only work as long as every window and vent is closed. They work by drawing fresh air in and cooling it to a set constant temperature for the horse area. These are a very good option but expensive and power hungry.
Lazy air

Muddying the water further and adding another level of complication to cooling is the fact that air is extremely lazy and this applies to all the options above with the exeption of AC. Now you have to bear in mind that your goal is to remove hot air and draw cooler air across your hot horses. I will use an extraction fan as an example here.

So, you are loaded with horses, all the windows are open and you turn on the fan to keep them cool. However, you have forgotten Mr Lazy air, he cannot be bothered to travel all the way across your horses and cool them, his far easier option is to take a direct route from the nearest open window straight to the extraction fan. Hot air will still be removed, but the cooling effect on your horses will be much reduced.
Now you have some trial and error ahead of you to get this working properly. Starting by partly closing the nearest windows to the fan, you should be able to even out air flow from each window so air has to travel over your horse to reach the exit fan.
For testing we did all this with a smoke machine and it was still surprisingly difficult, but very enlightening.
There you go, complicated but something to think on and I hope it helps.
Kevin..

 

[Red-1]

A lot of it is due to having an insulated roof, so the sun doesn't beat in like a shed.

Mine has the insulated roof, 2 head windows, 2 bum windows, a face window, a roof vent over the head and forced air over the quarters. It is a longstall with bars, so the air flow goes right through the box, and has an 8' roof so isn't stuffy. It is cooler than my house, many days!

I used it up to 38 degrees. That was to come home from camp where it warmed up while we were there - I wouldn't have deliberately set off in that heat!

 

[SEL]

I knew I could rely on this forum!

I need to get OH playing with the roof vent over the weekend I think (I'm too short.....). He's an engineer and has already muttered about angling it so it looks like that might help.

otherwise I'm bashing a hole in the side for another window.....

 

[Boulty]

I’m having issues with this in my box atm (it seems that by sorting out all the bits rain was leaking in I’ve also reduced the airflow!). Mine has a window by the butt, a roof vent, a window between the horse area & completely closed off tack area & then 2 tack area windows. It seems to get hotter than my old coachbuilt that literally had 3 windows (but a larger internal space & no dividing wall).

I’m going to try getting the aircon fixed (if it can be) & then opening the window between cab & horse area & seeing if that helps & also debating a second roof vent with fan or replacing my existing vent with one with a fan.

Would be interested in what others have found works (esp how to set my vent up as it didn’t used to stay on an angle so just used to fully open but it’s been fixed so should now, although again I think the way we’ve fixed it may have reduced the airflow)

 

[SEL]

@Squeak I've just pasted that into an email for my OH. Thank you so much.

Obviously we'll need to work with what we've got and I'm not planning on long distances especially when its hot, so hoping some tweaks will help.

@Boulty I also have a closed off tack area. Wonder if the door came off that it would help.

I might give one of the local horsebox places a call and see whether they can properly bash another hole for me (aka another window). Although given I nearly hit a barrier the other day I'm at risk of doing a DIY job at some point

 

[Identityincrisis]

I had the same issue with my young horse, he would sweat rivers even when it wasn’t that hot, a lot of this was due to nerves while travelling but I decided if it was more comfortable for him to travel in, he would hopefully get better.

At the time i had a roof vent, two small side windows in the upper half of the ramp and 2 in the back of the van although I have a really high wall (effectively a stallion wall) so I decided those more or less were ineffective. I decided to travel in the back one day to find out exactly what the air flow was like, it was nonexistent! I was very surprised.

I decided to put a roof fan in and it has helped hugely, i can now see on the camera the air flowing through his forelock he still occasionally, on a very hot day, has sweaty pits but that’s all, and he now travels like a dream which I expect wouldn’t be the case if I hadn’t sorted the airflow

 

[millitiger]

I've just put 2 x rechargable fans up in my horsebox and the difference they have made is remarkable.
I travelled on Sunday and my horse was lovely and cool when we arrived and he can be prone to sweating in the box.

Fans were £32 each and last around 10 hours on one charge so plenty for getting there and back on any of our horsebox journeys.

 

[Lady Jane]

@SEL I have same as @Red-1 but only 1 bum window and a fan that extracts or sucks in air. You can have extra windows etc put in but if your roof isn't insulated I would probably do that first. I have a gadget that tells me the temp in the back and the temp drops in mine by a few degrees when I start moving. Who built your box?

 

[Lady Jane]

@millitiger I was reading about this on FB. Which models did you buy? Where have you attached them?

 

[SEL]

I've just put 2 x rechargable fans up in my horsebox and the difference they have made is remarkable.
I travelled on Sunday and my horse was lovely and cool when we arrived and he can be prone to sweating in the box.

Fans were £32 each and last around 10 hours on one charge so plenty for getting there and back on any of our horsebox journeys.

Ooh can you let me know which ones?

@Identityincrisis I'm going get OH to drive me at the weekend because I suspect the airflow just isn't good enough

 

[Melody Grey]

@Squeak thanks for posting this, really useful.

 

[The Xmas Furry]

I have in my coachbuilt, a window each side nr horses head, one in back door, plus another small one in cab (the partition is hinged just to the side) and I get plenty of air through.
Also have fully lined roof, a breast wall so air can go right through and out.
I always park where i know the sun will beat down on the drivers side if no shade, it stays more cool than Shady bits outside. I see so many parking where the sun streams in the ramp side thus heating into the box.

Only once have i had one get too hot and that was picking up a friends neddy after a breakdown in 33 degrees, i think it was more the stress tho.

 

[Identityincrisis]

I have in my coachbuilt, a window each side nr horses head, one in back door, plus another small one in cab (the partition is hinged just to the side) and I get plenty of air through.
Also have fully lined roof, a breast wall so air can go right through and out.
I always park where i know the sun will beat down on the drivers side if no shade, it stays more cool than Shady bits outside. I see so many parking where the sun streams in the ramp side thus heating into the box.

Only once have i had one get too hot and that was picking up a friends neddy after a breakdown in 33 degrees, i think it was more the stress tho.

Yes, I always park so the sun isn’t shining into the horse area, even if he’s not stood in it, I imagine it makes a difference for when he’s onboard

 

[Chippers1]

This is interesting as I often worry about travelling in the heat. Mine is a light colour, plus Buzz has plenty of head room being only 14hh so that probably helps. It has two windows at the rear and a small window going through to the cab so I often open all the windows and when there's airflow it goes through to the back. He doesn't often come off sweaty so I think it works! If we keep having these really hot summers I will look into a roof vent too.

 

[Bernster]

@millitiger I was reading about this on FB. Which models did you buy? Where have you attached them?

Interested in this too please!

 

[millitiger]

@Lady Jane
@SEL
@Bernster

I have 2 x of these ones, I have cable ties them to my rug rack which is in the last partition, so they face the side of my horse.

Amazon.co.uk

 

[Squeak]

I've just put 2 x rechargable fans up in my horsebox and the difference they have made is remarkable.
I travelled on Sunday and my horse was lovely and cool when we arrived and he can be prone to sweating in the box.

Fans were £32 each and last around 10 hours on one charge so plenty for getting there and back on any of our horsebox journeys.

Sorry for bumping an old thread but do you think these fans would be powerful enough/ do enough to help with a horse standing in a 3.5t on a hottish day? Got a long day at a show next weekend and want to make him as comfortable as possible.

 

[SEL]

Sorry for bumping an old thread but do you think these fans would be powerful enough/ do enough to help with a horse standing in a 3.5t on a hottish day? Got a long day at a show next weekend and want to make him as comfortable as possible.

I've got one in after millitigers recommendation and I'd want more than one if he was in the lorry for any real length of time - although I've been sloshing down too so fan + wet horse = much cooler.

 

[millitiger]

Sorry for bumping an old thread but do you think these fans would be powerful enough/ do enough to help with a horse standing in a 3.5t on a hottish day? Got a long day at a show next weekend and want to make him as comfortable as possible.

I have x 2 in my 7.5t and in June it was 30c and we had a dressage comp- my horse was lovely and cool stood in the box with both fans directed on him.
They're attached to my rug rails at the back so the range covers him from mid neck to mid quarters (he is 17hh).

They make a big difference when travelling home too- he usually breaks out sweating on the way home from most events but not with these.

 

[Squeak]

I've got one in after millitigers recommendation and I'd want more than one if he was in the lorry for any real length of time - although I've been sloshing down too so fan + wet horse = much cooler.

I have x 2 in my 7.5t and in June it was 30c and we had a dressage comp- my horse was lovely and cool stood in the box with both fans directed on him.
They're attached to my rug rails at the back so the range covers him from mid neck to mid quarters (he is 17hh).

They make a big difference when travelling home too- he usually breaks out sweating on the way home from most events but not with these.

Brilliant, thank you both. I will get two ordered today.

 

[SEL]

Brilliant, thank you both. I will get two ordered today.

If I was out this weekend I'd get another! Mine is on cable ties to the window bars in the section in front of where the horse is. To avoid untying it to recharge I've got a portable battery charger thingy.

 

[Squeak]

If I was out this weekend I'd get another! Mine is on cable ties to the window bars in the section in front of where the horse is. To avoid untying it to recharge I've got a portable battery charger thingy.

Ooh that's a good idea, I've got one of those. I was thinking I could charge it to take with me so that I could blast the fans all day without worrying about it but hadn't made the leap that it would mean I wouldn't need to remove the fans for charging then.

 

[Boulty]

I’ve just bought one… going to hang it creatively in the box and also do something with my mini aircon. Hoping these plus hosing down before I set off (& doing a bib & belly clip) will keep pony cool this weekend. If the answer is yes I might be spending a lot of my non riding time with them directed at me!

 

[peanutsmumma]

Does anyone have a picture of the fans mounted in their lorries please ?

 

[Squeak]

Thank you so much for the recommendation of the fans. I had two going today whilst waiting between classes and they were brilliant, horse was cool and happy. In fact he was far better off than us trying to find some shade from the lorry and hopped off the lorry for his second class ready to go.

I've had them on at night in our bedroom too and have been surprised how effective they are.

 

[Keith_Beef]

A lot of it is due to having an insulated roof, so the sun doesn't beat in like a shed.

Series II, IIa and III Land Rovers were sometimes fitted with a "tropical roof". Basically, a white double-skin aluminium roof with a space of about an inch and a half between, open at the front and back edges. As you drive, air constantly passes through the space, keeping the inner skin of the roof cool.

Land Rover Series 2a , 1963 ,SORRY NOW SOLD TO WARWICKSHIRE | Jake Wright Ltd | Specialists in Land Rover and Range Rover | Yorkshire

Here for sale is a very n

www.jakewright.com

 

[Lady Jane]

@Red-1 & @Keith_Beef - you have just explained to me why my horse is cooler in my Theault Proteo than my 7.5t lorry - the Theault is fully insulated (and has several windows/roof vents etc). The 7.5 has lots of windows but isn't insulated