water tank insulation Orian Zeta

[Minnie]

I have just downsized from a Bessie 760 to an Orian Zeta (aka Nuevo) and see the underslung water tank is not insulated. Can anybody out there advise of a suitable material to insulate the tank bearing in mind it is a bit exposed under between the chassis members. (?)

[chas]

I have seen some vans with the underfloor tanks coated in a type of spray on insulating foam, how easy this is to apply I do not know . It could be easier to remove the tank and treat it and reinstall back into position. Your dealer should be aware of these type of jobs, if not it may be worth enquiring at C.A.K. tanks of Kenilworth. There is not much they do not know about motorhome water tanks. chas

[breakaleg]

Hi Minnie, the downside to insulating the tank is, it takes longer to unfreeze once it has.

pete

[Mike Chapman]

Hello Minnie,

 

Chas is spot on. CAK Tanks sell insulation blanket and the sticky tape to secure it. You can also use either strips of the blanket wrapped round the pipes to and from the tank and secure it with the tape, or buy some foam pipe insulation tubing from a local plumbers merchants and make it waterproof by wrapping in the tape.

 

Caution though, Pete raised a good point about freezing and also the tank may have to be removed to insulate it.

 

Regards,

 

Mike.

[Guest starspirit]

It might be easier to fit a small 12v (or mains if you use site hook ups?) heating element into the tank or maybe even box it in with plywood and run a branch from the warm air heating (if you have it?) around the tank?

 

Autosleepers build fine vans but always have had a reputation for being poorly insulated and unwinterised.

[Minnie]

Thanks for the ideas. I think I will give CAK Tanks a call and see what material they have then look forward to a nice job for the summer!

 

Mike

[Guest peter]

You can buy cans of spray on expanding (polyurethane) foam. or coat it wit polstyrene tiles or sheet. The sheet they use in between the walls of modern buildings is about 50mm thick and is easilly available at a builders merchants. Just don't use a solvent cement to stick it on, water based (latex) or PVA is o/k though.

[Guest starspirit]

Spray foam would be a pain to use especially upside down under a van as it expands very quickly and while expanding can exert a lot of pressure.

Even if you made a containment box first you might find that refitting the box and tank 'foamed up' would be next to impossible?

[Guest peter]

Foam would not exert any pressure unless contained an even then only minimal, it would just be more dense. I would use Polystyrene sheet.

[peejay]

Hi Minnie,

 

I had a Nuevo with the water tank internally mounted under the nearside settee (a factory option) which is their official factory 'solution' to winter camping.

Unfortunately they then ran the water pipe from the tank underneath the van to the waterpump on the other side which easily freezes (doh). I had the ASSC reroute the pipe (at their cost) through a covered channel under the floor to the other side of the van to connect to the waterpump. This worked fine until you got into really cold (alpine) conditions when it would still eventually freeze.

 

My point being that they use the same external tank but just relocate it under the settee, so it might be easier to relocate your tank in the same location and follow the same pipe routing for normal winter conditions, but if you want to use your van in alpine conditions then consider a different route for the pipe internally across the floor between the dinette seats at the front of the vehicle. Sounds like a lot of work but more effective than trying to insulate an underslung tank which is rarely a totally effective solution.

 

The only issue here is if you can do without the storage space beneath the dinette.

Unfortunately Autosleepers are not at the forefront for winterising the water systems on their motorhomes, unlike their european counterparts.

 

pete

 

[Brian Kirby]

Don't forget that no amount of insulation will prevent the tank from freezing, it will only extend the time it takes to do so.  As above, once frozen, the time to thaw out again will be similarly extended.

However, unless you are proposing to visit (or live in) areas where the temperature under your van will remain below freezing for extended periods, you shouldn't generally have a problem.

If you think freezing will be a problem, I don't think a heater would necessarily be the best solution.  Stored water should be kept at a low temperature, around 5C is I believe regarded as about ideal.  If you can get a heater that is guaranteed not to raise the water above that temp, fine, but then insulate the tank to protect the corners.  However, do check the heater is 12V powered, or dual voltage, and you have means to generate the necessary 12V power when on hook up.  If you use a mains only unit, your tank will probably freeze in the 60mph cold blast underneath, as you drive!

If none of that will work, you'll probably have to leave the tank empty and your water system drained, or face shifting the tank and all the water lines to the inside of the van, above the insulated floor.