heating

[steve_5065514]

Can anyone tell me how the blown air system works on a van. The best I've ever managed is tepid air blowing in the bathroom.

 

[moncman]

I would also appreciate advice. Our Lunar Zenith works quite well on the normal heater but once the blown air system is brought into play it cools to a gentle off-cold even when on max. On the plus side the cool air does feel nice and dry.

 

[RayS]

The warm air system has a fan which can be set either to manual - with you choosing the speed or automatic. In either case it is quite possible to blow air across the heating elements faster than it can become warm, so the first thing is to keep the fan speed low.

All the air gets pushed into the ducting system and will take the path of least resistance. So if you have a short length of duct with the vent into the van fully open, most of the warm air will come out here, rather than go down a long duct to the other end of the van.

So close, or nearly close, some of the vents - say in the living area if you want to heat the bed area or bathroom and vice versa. Put the heat on full ( 10 on the gas setting or 2000 on electric) and the fan on such that you can barely fell any coming out of the vents.

Do not expect instant warm up. i usually run the heater as convector - i.e. without any fan for the first 10 - 15 minutes and then put the fan on with the vents selectively closed. Even with vents seemingly closed there will be some airflow as they are not a tight shut-off.

Some modern vans have trunking which goes down through the van floor and then back up again. it is worth checking that this has some protection outside the van, as otherwise much of the heat will be lost here.

In the extreme you can use most Truma / Carver heaters with both gas and electric on at the same time for quick warm up, but do read your particular instruction book to make sure this is allowed.

If using gas in cold weather it should be propane not butane (see current threads elsewhere on the forum) as butane does not vapourise freely in the cold.

Hope this helps - another winter time trick particularly with a fixed bed van is to fit an electric blanket - uses relatively little current but gives a very cosy bed. how soft we get in old age !

 

[gary]

This question keeps coming up but the answers always the same, the blown air heating does/should work very well. I believe then the problem is how it's used.

The van will be very cold when you arrive on site so best to use both gas and electric on full for a fair while, this will belt some heat into the fabric of the van not just the air. Once the vans really warm then the gas can be turned off and the electric can be turned down to a temperature setting to suit you.

If you don't give the van plenty of time to heat up, you will be forever playing catch up as the fabric of the van constantly pulls heat from the air and you feel draughty.

The Truma fan is best used on 'A'utomatic, this allows the air temperature to control the speed, the number setting you choose then only dictates the maximum speed the fan can spin up to. Initially while gas and electric are used together you should choose 5, after that something to suit, perhaps off or 1 overnight and 2-3 during the day

On the subject of which wattage setting, the different wattages are to suit different amperage hook ups, 500w for 6amp, 1000w for 10amp and 2000 for 16amp, their not for setting the temperature of the van.

Both gas and electric are thermostatically controlled so will switch on and off automatically when required, the only difference the wattage 'should' make is how long it's on, ie, (and roughly speaking), 15 minutes at 2kw requires 30min at 1kw and an hour at 500w for the same amount of heating,

So if it does not work like that, theres something wrong with the control, this is more often than not the position of the electric sides temperature sensor and easily sorted. Another Truma problem is relay burn out, this means elements are not switching on, particularly the 2kw one!

There is though perhaps a good reason to leave on 500w overnight, better heat output is not to intense but on gently so for a longer period or perhaps permanently overnight.