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I have had no experience of blown air heating in caravans.  Please could you advise me on the following when using blown air heating from an electrical hook-up:

1.  Does the system produce a "dry heat"?  My wife is allergic to a dry atmosphere and a "dry heat" could aggrivate her condition.

2.  Are the fans noisy?  Will they prevent sleep at night?

3.  Can a domestic 240 volt timer be fitted to allow a 24 hour heating programme when using an electrical hook-up?  It would appear that thermostats are normally fitted, but not timers.  Why is this?

I would greatly appreciate any advice you can give.

Many thanks,  John Russell

Hi, by its nature an electric heater will produce a dry heat, try using the gas instead, this will produce a moist heat.

The fan does make a noise but its generally just a quiet hum, and doesnt interfere with sleep.

I suppose a timer could be fitted although Ive never seen one, and never been asked to fit one, If your using the van year round you will probably need it on all day anyway, and only on to take the chill off on summer evenings.

Hello Rob,

Thanks for your reply.  It looks like the gas option would be better for evening use and then switch over to a timer/electrical system before bed-time in order to programme the heating to come on in the morning.

Many thanks,

John

  When we go away and it is cold we leave it on all night it keeps the van nice and cosy.It does not dry the air that much because the van is quite do not hold heat in like a house does. The problem with leaving the gas on all night is you must use propane because it does not freeze at untill it gets well below freezing also if the flame was to go out and you have not got a carbon monoxide detecter you get poisioned

I don't think using gas will give a 'moist' heat as any moisture created is vented outside along with CO2.  The flame is sectioned off from the interior of the van, so the heat will be dry.  The good point is that it doesn't promote damp.  For this reason you cannot get poisoned. 

If the gas froze there would be no pressure anyway and hence no flow.

Brian

Quote: Originally posted by Fat Belly on 13/12/2008

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We have left the fan on a low setting all night and it is almost inaudible.

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Quote: Originally posted by waterman on 13/12/2008

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I have had no experience of blown air heating in caravans.  Please could you advise me on the following when using blown air heating from an electrical hook-up:

1.  Does the system produce a "dry heat"?  My wife is allergic to a dry atmosphere and a "dry heat" could aggrivate her condition.

2.  Are the fans noisy?  Will they prevent sleep at night?

3.  Can a domestic 240 volt timer be fitted to allow a 24 hour heating programme when using an electrical hook-up?  It would appear that thermostats are normally fitted, but not timers.  Why is this?

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Blown warm air heating in caravans, whether gas, electric or both does not introduce moisture into a caravan.  Gas combustion fumes are vented to atmosphere up a flue.

The fan speed can be varied.  At lower speeds it is virtually silent.  It is unlikely that you would notice fan noise and very unlikely that it would wake you during the night.

The gas heating system's electrics (including the fan) are all 12V, so that it can be used on a pitch without EHU.  You cannot control it using a 240V timer.

You could fit a 240V timer to control the electric heating - but obviously, you'd have to be competent to wire one into the caravan's 240V electrics.  I cannot see why you would want to do that anyway, as you could just turn the heating down (or off) when you go to bed.

Cheers
Andrew

 

 

Quote: Originally posted by rabbin8 on 13/12/2008

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Hi, by its nature an electric heater will produce a dry heat, try using the gas instead, this will produce a moist heat.

 

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Not in a caravan, the gas heater in a caravn is a completely sealed to the room heater which takes it's air in from below and then gets rid of it's burnt gases through a dedicated flue. The heat you get in the caravan is from a metal heat exchanger which simply heats up the air and convects it around the van. All the blown air system does is to distribute it evenly throughout the van.

Quote: Originally posted by janus on 13/12/2008

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Quote: Originally posted by rabbin8 on 13/12/2008

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Hi, by its nature an electric heater will produce a dry heat, try using the gas instead, this will produce a moist heat.

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Not in a caravan, the gas heater in a caravn is a completely sealed to the room heater which takes it's air in from below and then gets rid of it's burnt gases through a dedicated flue. The heat you get in the caravan is from a metal heat exchanger which simply heats up the air and convects it around the van. All the blown air system does is to distribute it evenly throughout the van.

 

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It is only the air supplied to ignite the gas that is sealed from the heater.  The air that passes into the van via the finned ducts is drawn from outside the van by vents, and this air will carry a moisture content, which varies with atmospheric conditions.

Bertie.

Quote: Originally posted by The 2 Tops on 14/12/2008

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It is only the air supplied to ignite the gas that is sealed from the heater.  The air that passes into the van via the finned ducts is drawn from outside the van by vents, and this air will carry a moisture content, which varies with atmospheric conditions.

Bertie.

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And if that is the case in the same way the warm air that comes with the electric heating is drawn in through the same ducts and will carry the same amount of moisture as the heat that comes from the gas fire. Mind you from looking at the installation book for the trumatic 3002 that is fitted in my van all that I see is a heater which takes the air that it burns via a sealed vent under the van and the exhaust gases leave via a sealed pipe that goes through the roof. the heat from the burner is transmitted to a heat exchanger which simply heats whatever air there is in the room  and circulates by convection, though there is some radiant heat if you are close enough to it. There are no vents of any sort anywhere near the fire, though there are plenty elsewhere.

Quote: Originally posted by The 2 Tops on 14/12/2008

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It is only the air supplied to ignite the gas that is sealed from the heater.  The air that passes into the van via the finned ducts is drawn from outside the van by vents, and this air will carry a moisture content, which varies with atmospheric conditions.

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My understanding is rather different.

The combustion air for the gas is drawn from inside the caravan and, after combustion, it passes through a heat exchanger and then to outside via a flue. 

Heating air is recirculated within the caravan and is drawn from the caravan not from outside.  If it were drawn from outside, you'd need a heater that was twice as big; the system would be very inefficient and you would use a lot more gas than you need to. 

Cheers
Andrew

Running on gas the air for combustion is drawn from outside under the van and exits through the roof, at no time is air from inside the van directly or otherwise involved with the combustion.

The heat from the gas fire then will be as dry or moist as using electric heating.

Where it should vary is the different type of ventilation in a van as compared with the home, the air is changed much more often in the van and therefore should remain more moist than in the home.

Beyond that, Truma/Carver supply the 'comfort kit' this is a duct drawing air directly from outside and mixing it with the blown air directly behind the fire. The amount of air can be varied by way of a simple butterfly valve, although then designed more for summer it should be useful in winter keeping the air fresher.

Quote: Originally posted by vkd21 on 13/12/2008

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also if the flame was to go out and you have not got a carbon monoxide detecter you get poisioned

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Could you use a socket plug timer that is usually used for turning on and off table lamps?  Do not know enought about caravan electrics to know  but had thought of possibly using one if we were camping in cold weather.

Carol