Tube heaters, are they any good?

Matt341

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Hi All,

Following on from my thread about dehumidifiers a couple of months ago, I decided to try it out before splashing out on anything expensive. (We already have a B and Q one which I use now and then in my office)

So I put it on the floor in the passageway between the heads, bow cabin and main cabin leaving the heads door slightly open.

I decided not to drain out at this point and to leave the tank fill, it cuts out when full and this was tested before putting it in place.

I put it on for about 4 hours a day in the morning and 2 hours early evening. After a week I was stunned to find the container was not full to the limit, it was about just over half.

I cant say the boat felt any different and I still had to put the heating on whilst onboard.

It also used a fair bit of power to have it running.

Im now thinking whether it would be worth putting in some kind of heating instead.

I have a small ish tube heater which we use in the conservatory so im wondering whether it will be worth putting it on the boat on a timer, e.g. from 05:00 till 09:00.

My concern with the dehumidifier was whether it would freeze in cold weather and even by running a dehumidifier doesnt prevent pipes from freezing, although im not sure the tube heater would either.

It doesnt use much power but after being on for about half an hour it can really give off some heat.

Im wondering if anyone else uses tube heaters? I was wondering whether it would be a risk leaving on timer on the boat through the winter?

I dont want it to turn the boat into an oven as this will probably cause condensation but just something that will keep the inside from being frozen.

Last year we didnt put any form of heating on our previous boat and we went down one day to find that the olive oil had frozen in its bottle!!!

Thanks
Ian
 
Hi All,

So I put it on the floor in the passageway between the heads, bow cabin and main cabin leaving the heads door slightly open.

This is probably the coldest spot - You would be better putting it as high as possible.

I cant say the boat felt any different and I still had to put the heating on whilst onboard.

A dehumidifier should not be considered a replacement for a heater - in fact you normally would need to supplement the dehumidifier with a heater to get it to work properly when cold.


I have a small ish tube heater which we use in the conservatory so im wondering whether it will be worth putting it on the boat on a timer, e.g. from 05:00 till 09:00.

What is the wattage of the heater? - Tube heaters are usually very low and at best will only take the chill off - Electric heating is directly proportional to the wattage of input - there is no 'magic' heater that can produce heat disproportionate to the energy put in.
Boats are not very good at holding heat in general so cool back down again quickly once the heat is turned off.



I dont want it to turn the boat into an oven as this will probably cause condensation but just something that will keep the inside from being frozen.

??? - heat will not cause condensation - it may get moisture out of fabrics and bedding that will condense on windows, but once it's in the air a dehumidifier should take it out.
 
I run a couple of tube heater and a dehumid.... but not at the same time all on timers... works well for me...

I leave the domestic water taps open just in case the pipes freeze.
 
As far as I can see the smaller dehumifiers are petier cooled and thus are relatively power hungry for their performance. I see the main reason for tube heaters as keeping the air moving and a little bit of heating, which with good ventillation keeps condensation and damp at bay. For anti frost I tend to use a fan heater with a frost setting so that if the temperature does drop you have a decent heat input to prevent freezing.
 
I think you would be better off running it for a single 6 hour period rather than a 4 and 2 hour stint. It takes a while to get going so the 2 hour stint especially, is probably doing very little.

I use one every winter like this and the boat always feels warmer and drier than it ever did before.

The best model, if you can spend the money, is the X dry.
 
My tube heaters are only 60 watt, so putting them on a timer does not make any significant difference. However putting them on a frost stat does, so that if the cabin temperature falls below a certain level say 8 degrees C, then they come on and prevent frost damage.
 
I have one of these

As far as I can see the smaller dehumifiers are petier cooled and thus are relatively power hungry for their performance. I see the main reason for tube heaters as keeping the air moving and a little bit of heating, which with good ventillation keeps condensation and damp at bay. For anti frost I tend to use a fan heater with a frost setting so that if the temperature does drop you have a decent heat input to prevent freezing.

http://www.ebacdirect.com/product-list.php?parent=2

they are very good, its amazing what it can pull out when required to ( leak @ home )
 
......tube heaters as keeping the air moving and a little bit of heating, which with good ventillation keeps condensation and damp at bay. For anti frost I tend to use a fan heater with a frost setting so that if the temperature does drop you have a decent heat input to prevent freezing.

THIS IS WHAT WE DO. We have a tube heater in each cabin and use a 'FAN' heater on blow, a timer and a trip to blow the Air out of the boat. Warm air will hold more moisture than cold air. So if the inside is a fwarmer than the outsid and this air is then pushed outside it takes the moisure with it.
 
After driving around numerous B&Qs and Homebases trying to find tube heaters, I thought sod it and bought a desiccant dehumidifier for £150 - Best on test in the PBO test on dehumidifiers.

I'll be having a collection to help me pay the lecky bill in spring :D
 
Thanks for all the replies,

I see I made some mistakes with the dehumidifier.

My only other concern with the dehumidifier is drainage? If it did fill up it would be useless until I could get down to empty it.

I have seen a few boats where they drain into the sink but then this would mean leaving open the seacock which I really dont want to do.

How effective are fan heaters? I have used convector heaters and oil filled on the boat but have no experience of fan heaters.

Would it be more suitable to put on a convector heater on timer but also set the thermostat.

Or maybe get an oil filled with thermostat??

I really want to use a timer as I can control how much power is used.

When we stayed onboard last it was very cold when we arrived and SWMBO put the oven on for some food, all the windows condensed badly but when the boat reached a nice temperature the windows cleared.

Many Thanks
Ian
 
Thanks for all the replies,

I see I made some mistakes with the dehumidifier.

My only other concern with the dehumidifier is drainage? If it did fill up it would be useless until I could get down to empty it.

I have seen a few boats where they drain into the sink but then this would mean leaving open the seacock which I really dont want to do.

How effective are fan heaters? I have used convector heaters and oil filled on the boat but have no experience of fan heaters.

Would it be more suitable to put on a convector heater on timer but also set the thermostat.

Or maybe get an oil filled with thermostat??

I really want to use a timer as I can control how much power is used.

When we stayed onboard last it was very cold when we arrived and SWMBO put the oven on for some food, all the windows condensed badly but when the boat reached a nice temperature the windows cleared.

Many Thanks
Ian

[I have seen a few boats where they drain into the sink but then this would mean leaving open the seacock which I really dont want to do.]

i used to do that but now only use the integral tank & find that sufficient.
i would never leave a fan heater on for extended periods without being on board as i dont consider them safe enough, an oil filled rad is much better. a timer is quite ok
 
Thanks for the reply,

I was wondering about the fan heater and whether it was dangerous to leave on because of the fan running etc.

How powerful are oil filled??

They look pretty robust so it could be stored in one of the under seat lockers when not in use.

I know it depends on wattage but say a 1kw, would it give off enough heat to keep a 29 footer comfortable or would I need something more powerful, say 2kw?

The tube heater keeps our conservatory comfortable but then the heat from the house helps with that as well.

Thanks
Ian
 
Thanks for the reply,

I was wondering about the fan heater and whether it was dangerous to leave on because of the fan running etc.

How powerful are oil filled??

They look pretty robust so it could be stored in one of the under seat lockers when not in use.

I know it depends on wattage but say a 1kw, would it give off enough heat to keep a 29 footer comfortable or would I need something more powerful, say 2kw?

The tube heater keeps our conservatory comfortable but then the heat from the house helps with that as well.

Thanks
Ian

its the element that causes probs with fan heaters if the fan stops the element Glows red :eek:

my oil filled rad is 1kw max switchable to 400 & 600watts + an inbuilt variable thermostat on a 37 footer
 
Thanks for the reply,

I was wondering about the fan heater and whether it was dangerous to leave on because of the fan running etc.

How powerful are oil filled??

They look pretty robust so it could be stored in one of the under seat lockers when not in use.

I know it depends on wattage but say a 1kw, would it give off enough heat to keep a 29 footer comfortable or would I need something more powerful, say 2kw?

The tube heater keeps our conservatory comfortable but then the heat from the house helps with that as well.

Thanks
Ian

I really don't like the idea of leaving 'open element' heaters (fan heaters, convector heaters etc.) unattended for any length of time.
I much prefer oil filled rads.
With regards to using a timer to control the power, I would suggest that a thermostat control (and I mean a good quality plug in one that works on temperature, not a bi metal on off thermostat as found in convector heaters) would be a better solution.
The thermostat will only switch the heater on when heat is required, and most importantly will switch it on OUTSIDE of your plug in timer if it gets very cold.
If the heater is there to protect the boat from the cold, I really don't think you will do a better job than the thermostat by setting the heater to come on a predefined times.
You will just have to accept it will cost what it costs to do the job.
 
Thanks for the replies,

not good news if the fan stops then, especially as a lot of the fan heaters are made from plastic.

I need to be careful with power consumption as the marina supply is limited to 13 amps so with a 1.2kw calorifier, battery charger, fridge, kettle, tv and then heating it could trip.

This is why it would be handy to have the 400, 600 & 1kw option as we could turn down to 400 when using other items but still have the backround heat.

I think our tube heater is very low wattage, about 250watt but then this will reflect in the output heat.

I guess the other option is to set a thermostat, then put the timer set to 12 hours, e.g. 19:00 till 7:00, as this is when its likely to be the coldest.

I dont like the thought of the fan or convector heater compared to oil filled. Oil filled seem much safer.

Many Thanks
Ian
 
The idea is to keep the inside air warmer than the outside air

Thanks for the reply,

I was wondering about the fan heater and whether it was dangerous to leave on because of the fan running etc.

How powerful are oil filled??

They look pretty robust so it could be stored in one of the under seat lockers when not in use.

I know it depends on wattage but say a 1kw, would it give off enough heat to keep a 29 footer comfortable or would I need something more powerful, say 2kw?

The tube heater keeps our conservatory comfortable but then the heat from the house helps with that as well.

Thanks
Ian

We only run the fan in BLOW mode. No heating and it’s been fine for 15 years (although we replace the blower every 5 or so years).

As for the power of the Tube heaters – I don’t know, they are not that powerful. The idea is to keep the inside air warmer than the outside air and to blow the air outside the boat via slightly open hatches which lock but allow ventilation and keep rain out.

Never had any problems with moisture in the UK, Scandinavia or Spain when boat has been left like this.

The technique was shown to me in Norway where many people used to leave a 120w desk type light on to achieve the same thing. Well they used to when you could get them eleccy was very cheap there in the 90
 
If you have access to mains electricity it is much better to heat and ventilate. De-humidifiers just suck the air in from outside and that has unlimited moisture. They only really work when the area they are in is more moist than outside.

Get a Dimplex 500 heater for about £30 and leave it on all the time. If you have dorades near the bow and a vent further aft the boat will stay warm and very dry all winter. On our 45 ft boat we have two Dimplexes and the internal temperature never drops below 12 degrees C.
 
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