# Catalytic Gas Heaters



## Brockley (Jul 12, 2021)

Does anyone have experience of these heaters. I just bought one of them second hand









						Aks Mini Catalytic Gas Heater  | eBay
					

Used but still works as it should  still available on line around £200.



					www.ebay.co.uk
				




I can only describe our brand new Webasto diesel heater (well 2019) as a piece of sh1t. Twice now our ‘friendly dealer’ fobbed us off saying their local Webasto specialist plugged the unit into their diagnostic machine and twice the computer said yes!.

knowing now it’s less than useless during cold weather and despite describing exactly how it has no thermostatic control, my complaints fell on deaf ears. I swear I will never ever entertain this dealer again for so many reasons. Their incompetence is well into the next level. I got a missed call from them a couple of days ago saying that our van was ready for collection having had ‘all of the snags completed’ and a habitation check sorted. Great news considering I got the van back weeks ago and we are out touring in it now!

Anyway back on track I did some trials with this heater at home preempting next winter and it seems pretty good. I intend to run it from external canistered gas. The Americans do this a lot……not talking about their much favoured Mr Buddy heater which produces a lot of condensation, catalytic heaters are more efficient and don’t even show a flame. This one seems to be similar to the American ‘Wave heater’.

It sips gas, small 220g gas canisters will run it for 6 hours!

Do any of you have any views about catalytic gas heaters?

By the way, the sh1t dealer I spoke of rhymes with ‘Slybridge’.


----------



## Boots (Jul 12, 2021)

Hi,

Had one some years ago, very good, low gas use, plenty of heat.

Personaly I never use'd it whilst asleep(!) plus plenty of fresh air needed, other wise all good.


Boots


----------



## n brown (Jul 12, 2021)

all i know is they give out  carbon mono like any other heater


----------



## mistericeman (Jul 12, 2021)

Sort the Webasto out OR fit a eberspacher.... 

Eberspacher is IMHO THE only sensible option for extended winter trips away.


----------



## molly 2 (Jul 13, 2021)

Not a good idea,


----------



## molly 2 (Jul 13, 2021)

Oxygen  depletion is a dangerous  problem some have built in cut outs . They also produce a lot of condensation , Google catalytic  marine heaters . Hopefully it will put you of ,


----------



## Mick H (Jul 13, 2021)

Brockley said:


> Do any of you have any views about catalytic gas heaters?


Yes, we use a catalytic heater. It's a "Thermix", which, unfortunately, aren't available, anymore, in the UK.
It produces 900 watts, but seems much more. I fitted it, when our motorhome was new, back in 2005. We have used it ever since, and it continues to give us trouble free heating, without using any battery power, of course.
It has a oxygen depletion sensor, and, being catalytic, does not produce any carbon monoxide. Only problem experienced, was a blocked jet, which was easily sorted.
Incidentally, we also use a living flame catalytic wall fire, in our lounge, at home. It too, has been trouble free, over many years.


----------



## trevskoda (Jul 13, 2021)

Any gas or even coal these days requires a venting port by law, gas heating other than a caravan type heater will or could be the end of you, all diesel blow heaters should have a stat fitted, get someone who knows what there doing to have a look.
Not forgetting gas will have water running down the windows like a waterfall unless an indirect caravan type.


----------



## n brown (Jul 13, 2021)

i stand corrected .still wouldn't have one though https://cpsc-prod.ctacdev.com/s3fs-public/pdfs/CO03.pdf


----------



## trevskoda (Jul 13, 2021)

Nor me.


----------



## Mick H (Jul 13, 2021)

I'll post again, and let you know, if our catalytic heaters kill us.


----------



## SquirrellCook (Jul 13, 2021)

https://motorhomebuilder.com/threads/aks-gas-catalytic-heating-systems-alke.66794/


----------



## Brockley (Jul 13, 2021)

mistericeman said:


> Sort the Webasto out OR fit a eberspacher....
> 
> Eberspacher is IMHO THE only sensible option for extended winter trips away.


Slybridge have had the Webasto specialist look at it twice now and both times it was given a clean bill of health. Of course was only a diagnostic computer saying it was fine. Strangely we had an Eberspacher heater in the last van and it was sh1te too.


----------



## Brockley (Jul 13, 2021)

SquirrellCook said:


> https://motorhomebuilder.com/threads/aks-gas-catalytic-heating-systems-alke.66794/


I entirely get what these U.K. poster are saying and chemistry is indeed chemistry, but one of them was seeing a flame so the unit was definitely not working properly. Have a look at what they are using widespread in the states, in particular the ‘Wave’ units. Despite looking, I haven’t found any gas gas gas stories from over the pond yet.


----------



## mistericeman (Jul 13, 2021)

Brockley said:


> Slybridge have had the Webasto specialist look at it twice now and both times it was given a clean bill of health. Of course was only a diagnostic computer saying it was fine. Strangely we had an Eberspacher heater in the last van and it was sh1te too.


I've worked on eberspachers for many years (and had them in many vehicles) 
Any old/poorly maintained heater will give problems (ebers included) 
However in my experience, well maintained and correctly installed units often run for years without issues. 

As for catalytic heaters.... In enclosed spaces... 
It's a no from me I'm afraid.


----------



## Brockley (Jul 13, 2021)

So what are your thoughts about the safety of the catalytic ‘Wave’ heaters installed in thousands of American RV’s, are they dangerous?


----------



## trevskoda (Jul 13, 2021)

Brockley said:


> So what are your thoughts about the safety of the catalytic ‘Wave’ heaters installed in thousands of American RV’s, are they dangerous?


Explains why there all a dozy lot.  head down now.


----------



## wildebus (Jul 13, 2021)

I've seen quite a few videos on those heaters.

Look quite good but seem to be quite like the Electric Halogen heaters in that the heat is very directional?  So would have be careful of how it is positioned and as a general space heater they don't seem that useful unless you can put up with the high front heat as well while warming up the van?
From what I recall, dust is a major enemy of them?  They need to be covered whenever not in use to keep them as clean as possible.

If I had a Webasto diesel heater fully fitted which was playing up, I think personally I would invest in getting that sorted out rather than spending the money on one of these Catalytic heaters and then enjoy the nicely distributed central heating from the Webasto.


----------



## Mick H (Jul 13, 2021)

wildebus said:


> I've seen quite a few videos on those heaters.
> 
> Look quite good but seem to be quite like the Electric Halogen heaters in that the heat is very directional?  So would have be careful of how it is positioned and as a general space heater they don't seem that useful unless you can put up with the high front heat as well while warming up the van?
> From what I recall, dust is a major enemy of them?  They need to be covered whenever not in use to keep them as clean as possible.
> ...


As far as I know, most work on the convection principle. Both of ours certainly do, and, having no flue, all the heat generated, is used, for warming. Very efficient, compared with other gas appliances.
We don't cover them, to stop dust, and although it obviously collects, and so tends to smell, when first used, each year, it doesn't seem to make any difference.
Dust collects on all heaters, including our Truma boiler, which smells too, until the dust has been burned off.
What I like about them, is, the instant heat, as with many gas fires, although it does take some time to warm up the whole van, naturally.
On a personal note, using a catalytic heater, is probably another reason that we haven't yet needed solar panels, which many of you can't live without.


----------



## wildebus (Jul 13, 2021)

Gas appliances are inherently inefficient generally when it comes to converting gas to energy.
You can heat the inside of a van pretty well using a gas cooker purely as a by-product of cooking dinner


----------



## trevskoda (Jul 13, 2021)

Depends how big the dinners are fatso.


----------



## wildebus (Jul 13, 2021)

trevskoda said:


> Depends how big the dinners are fatso.


I have still to use my MH Cooker really!  Used the oven to finish off a baked tattie a few days ago.  Mmmmm.  Used the Microwave for the pastie though.

I remember just after I fitted Diesel Heater #2, it stopped working just before I went away for a couple of nights.   Instead of using the Induction Hob to boil some water, I used one of those portable camping stoves instead - two mugs worth of water heated for hot chocolate and the van was nice and toasty


----------



## molly 2 (Jul 13, 2021)

When the temperature  falls  in winter  I leave  the blown air heating on 24 hours  dropping the thermostat  at night  ,cant see the point in having an expencive  heating system  and  being cold ,


----------



## Brockley (Jul 13, 2021)

wildebus said:


> Gas appliances are inherently inefficient generally when it comes to converting gas to energy.
> You can heat the inside of a van pretty well using a gas cooker purely as a by-product of cooking dinner


We can’t eat all the time as much as I like my food. The AKS heater is very efficient……surprisingly so, a 220g cartridge of butane lasts over six hours. Apparently they rely on a chemical reaction rather than conventional combustion and condensation is minimal. As Mick says the heat output isn’t directional.

The Webasto we currently have which has been given a clean bill of health (computer readouts to ‘prove this’) by ‘expert’ Webasto engineers yet we know it has a mind of its own.

The Eberspacher we had failed and was temperamental much of the time, the controllers are very expensive too for all they are!

Both types seem to affect our noses and throats because of the type of heat they give out, especially if used over a few days.

Gas heaters are common in the states, particularly in medium and larger RV’s. The level of ventilation recommended is also surprisingly low. I don’t like the look of the Mr Heater Buddy (established 1984) because they are exactly like conventional gas heaters and create a lot of condensation. The Camco Olympian Wave heater (not sure when Camco first introduced them) was what spurred me onto getting a catalytic heater to evaluate. So far so good as it produces very natural heat more like a real coal fire which we like.

Litigation is one of the biggest industries in the states. If they are so unsafe how are both of these manufacturers still in business?

Getting bit like a gas gas gas thread this


----------



## Brockley (Jul 13, 2021)

molly 2 said:


> When the temperature  falls  in winter  I leave  the blown air heating on 24 hours  dropping the thermostat  at night  ,cant see the point in having an expencive  heating system  and  being cold ,


I would never leave any heater on all night In a van.


----------



## mistericeman (Jul 13, 2021)

molly 2 said:


> When the temperature  falls  in winter  I leave  the blown air heating on 24 hours  dropping the thermostat  at night  ,cant see the point in having an expencive  heating system  and  being cold ,



I detest being cold..... 
Didn't like it as a kid and I'm to fat to ride my bike to keep warm these days..... 

I go away in the van to have fun and enjoy myself... 
Hence I spent the money on a brand new genuine eberspacher and fitted it.... 

5 years of hard use and its still going strong ready to go in the motorhome


----------



## molly 2 (Jul 13, 2021)

mistericeman said:


> I detest being cold.....
> Didn't like it as a kid and I'm to fat to ride my bike to keep warm these days.....
> 
> I go away in the van to have fun and enjoy myself...
> ...


Definitely  beats  putting the kettle on ,


----------



## Brockley (Jul 13, 2021)

Back on track……….catalytic gas heaters are favoured extensively in the states and have been for a long time, are there any experts here who can explain why they are unsafe?


----------



## FULL TIMER (Jul 13, 2021)

Brockley said:


> So what are your thoughts about the safety of the catalytic ‘Wave’ heaters installed in thousands of American RV’s, are they dangerous?


Most of the ones I've worked on over the years have had gas / co detectors built into the gas supply system so the minute anything is detected it automatically shuts the gas supply down, however I've also never come across a catalytic heater in one either.


----------



## Brockley (Jul 13, 2021)

FULL TIMER said:


> Most of the ones I've worked on over the years have had gas / co detectors built into the gas supply system so the minute anything is detected it automatically shuts the gas supply down, however I've also never come across a catalytic heater in one either.


So you must be an expert in the maintenance and repair of gas heaters traditional to campers in the U.K. which are quite different in nature. If I interpret you correctly, during the time you have been doing this you haven’t come across a catalytic heater installed in a van? If so that’s very interesting and confirms my thinking that not many people this side of the pond know very much about them and how they work other than to raise eyebrows and say they are unsafe in this application.

Does anyone here specialise in catalytic type gas heaters though? I‘d really appreciate any expert advice about them.


----------



## trevskoda (Jul 13, 2021)

To be honest i have never used my heater, prob don't work anyway, but I'm warm under a blanket and or a sleeping bag, I have slept in snow with just a bag and waterproof cover and the Russians never knew I was there.


----------



## Brockley (Jul 13, 2021)

Might be taking the same tack Trev if anyone can conclusively explain why this type of heater is unsafe


----------



## Big Chief (Jul 13, 2021)

Brockley said:


> Might be taking the same tack Trev if anyone can conclusively explain why this type of heater is unsafe


Catalytic Heaters are not unsafe provided your ventilation hole are not blocked. The only real drawback to any naked gas flame in a van is excessive condensation.


----------



## SquirrellCook (Jul 13, 2021)

I bought one some years ago for a damp and drafty house, worst thing I ever did. The idea was to stop ice forming in the house overnight, that bit worked at the expense of feeling ill in the morning.


----------



## Brockley (Jul 13, 2021)

Might that be anything to do with the extent of the damp in the house as you say there was plenty of ventilation


----------



## trevskoda (Jul 13, 2021)

SquirrellCook said:


> I bought one some years ago for a damp and drafty house, worst thing I ever did. The idea was to stop ice forming in the house overnight, that bit worked at the expense of feeling ill in the morning.


The old calor heaters had the water running down the windows and head in a spin, though the other type may be safe but for me diesel indirect heaters is the way to go.


----------



## molly 2 (Jul 14, 2021)

I doubt any one in the forum has personal experience of them as they went out favour many years ago, I had one in a boat about 30 years ago but used it for short periods and never felt safe with it , on some people fitted  them in early touring caravans before flued gas heaters were fitted .Coleman used to make camping version but stopped years ago,  just my opinion if they were safe people would still use them but they don't


----------



## molly 2 (Jul 14, 2021)

Have a look at the Chinese portable deisel heaters with built in fuel tank about £90  Ebay


----------



## Brockley (Jul 14, 2021)

It‘s obvious that not many people on the forum have experience of catalytic gas heaters, but loss of favour in the U.K. doesn’t prove anything about their safety and that’s what I’ve been asking for - proof one way or the other and not personal favour or assumption. 

I wonder why they are so popular they in the states, is it because they don’t care about personal safety or could it be that they serve a purpose? They certainly use very little gas for the return of heat.

I‘ve looked at Chinese knock off deisel heaters on fleabay but as already mentioned we really don’t get on with the type of heat from deisel heaters, it’s very dry and affects our noses and throats (both Eberspacher and Webasto).


----------



## Nabsim (Jul 14, 2021)

If you are after some sort of evidence didnt Nigel post a document earlier on? Someone did but I haven’t scrolled back. I did open if but didn’t read it so no idea if it was for or against this type of heater in vans 

edit: yes just checked, post #9 has link to document


----------



## SquirrellCook (Jul 14, 2021)

Brockley said:


> it’s very dry and affects our noses and throats (both Eberspacher and Webasto).


It sounds like your using it as instant heating and having it set too high.  Leave a large bowl of water somewhere to help with the humidity.


----------



## Okta (Jul 14, 2021)

Brockley said:


> Does anyone have experience of these heaters. I just bought one of them second hand


Many years ago I used a catalytic gas heater when camping in a tent but I wouldn’t use one in a motorhome. They give off a vast amount of water vapour which is a recipe for condensation and in an enclosed space they make the air feel very stuffy.

We also have a large one in our living room which we *never* use. It was fitted by the previous owner as a focal point without the cost of buying one with a proper flue. We tried it once but within 30 minutes the air in the room was foul, despite the essential large air vent. Like any gas appliance it is only safe if it has a good free flowing air supply.


----------



## Brockley (Jul 14, 2021)

Nabsim said:


> If you are after some sort of evidence didnt Nigel post a document earlier on? Someone did but I haven’t scrolled back. I did open if but didn’t read it so no idea if it was for or against this type of heater in vans
> 
> edit: yes just checked, post #9 has link to document



The first thing that struck me about that research was how old it is. It used two types of ‘Rosemount’ heaters described as the only commercially available catalytic gas heater available to study in 1999. It set out to “address the potential CO poisoning hazard that can result when propane heaters are operated in small-enclosed areas that are poorly ventilated, such as a tent”.

The second thing I noticed is just how small the unventilated test chamber was 6.6ft x 3.9ft x 3.9ft. That’s very small, yet the study concluded a healthy adult should suffer no ill effects after 6.5 hours exposure!!

Basically the test was deliberately carried out without adequate ventilation to see if it met the voluntary standard at the time of testing. 

Not much help really but does show some interesting data.


----------



## Brockley (Jul 14, 2021)

SquirrellCook said:


> It sounds like your using it as instant heating and having it set too high.  Leave a large bowl of water somewhere to help with the humidity.


There is no level setting on mine, I think they give off humidity rather than needing it, however the level of humidity is far less than naked flame gas heaters.


----------



## SquirrellCook (Jul 14, 2021)

Brockley said:


> There is no level setting on mine, I think they give off humidity rather than needing it, however the level of humidity is far less than naked flame gas heaters.


No, the diesel heaters.


----------



## molly 2 (Jul 14, 2021)

Have a google at marine catalytic heaters ,boats are the only place I have seen fitted in the last 30  years ,as the heat is caused by a chemical reaction their is less risk of fire .a boat owners biggest fear. It is clear you will  not get the answers you are looking for so it is make your mind up time , I'm  out


----------



## Okta (Jul 14, 2021)

Brockley said:


> They certainly use very little gas for the return of heat.


A catalytic heater ends up with the same result as a non catalytic one. The butane (or other gas) is converted into heat taking oxygen from the surrounding air. The catalyst allows the process to happen without a naked flame but the emissions are the same i.e. carbon dioxide and water vapour. When I bought one 40 years ago they were sold as being safer for camping because there was no naked flame.


----------



## st3v3 (Jul 14, 2021)

Brockley said:


> , I think they give off humidity rather than needing it.



Diesel heater? No. It takes air in from inside the van, passes it over a bit thing and blows it back into the van. No way to introduce moisture.


----------



## Brockley (Jul 14, 2021)

SquirrellCook said:


> No, the diesel heaters.


Yes tried that with diesel heaters, still affected us and with both types they recommend turning them up full on start up and then dialling in the required setting.


----------



## mistericeman (Jul 14, 2021)

Brockley said:


> Yes tried that with diesel heaters, still affected us and with both types they recommend turning them up full on start up and then dialling in the required setting.


Eberspacher do a initialisation run as part of the start up... 
Fan on full speed and fuel ramped up before dropping back to idle when temp set on controller is reached (setting temp too high is a common error as it causes the heater to run through its initialisation run more often.... Using more fuel AND more battery power (around 8 amps at max.... Dropping down to under 2 at idle) 
I'm always interested in the comments regarding 'dry heat'... 

The eberspacher/Webasto diesel heaters re-cycle air in the cabin space.... Passing it over a heat exchanger then back into the room.... 

Where does the moisture go that its removing from the air? 

I understand that certain types of combustion heating introduce moisture from the combustion process in none indirect heating ... 
Lpg/parrafin/catalytic etc 

But indirect heat can't really alter humidity levels unless you were sat with enough windows open to allow the increase in cabin air to drive off moisture in the air to the outside environment.


----------



## trevskoda (Jul 14, 2021)

st3v3 said:


> Diesel heater? No. It takes air in from inside the van, passes it over a bit thing and blows it back into the van. No way to introduce moisture.


Heat exchanger its the thingy. 
All non gas heater will over time dry the air same as central heating in a house, good for van keeping damp at bay, but just place a glass of water or leave some in the sink.
Rememeber your exhaled breath is full of moisture, along with your socks and other openings around the body, burp.


----------



## Caz (Jul 14, 2021)

Mum & Dad used to use a catalytic heater in their Autosleeper campervan back in the 1980s. Never did them any harm.

I did get it out of the garage some years back, cleaned it up intending to use it, but I couldn't get it to work so I gave it away to another camper who reckoned he could get it going again. Don't know if he did.


----------



## Boots (Jul 15, 2021)

Hi All,

Just a reminder that I posted earlier that I had used one in a camper van.

Good bit of kit just have plenty of ventilation as it can get a bit 'stuffy' and I personally would not sleep with it on.

I do have one going spare at the moment but when I offered it for sale some time ago on this site it drew a number of bad,(poorly informed) comments.

Nuff said.

Cheers


Bootys


----------

