Catalytic Heater for the Puck

 The fitted Gas Heater was an option when buying and new Eriba Puck from a dealer.  In the later Pucks, the heater fitted was the small but efficient Trumatic S2200. Although a handy and compact means of heating the van in colder weather, it did mean the sacrifice of one of the cupboards in order to house the heater. As many caravaners limited their touring to the summer months, and with many visiting campsites with main hook ups, then many bought the caravan without the optional heater. Instead, small oil filled radiators, or fan heaters were used when heating was needed.

I am a big fan of basic CL type sites, particularly the really stripped back sites which don't provide power. With my solar panel, I can last indefinitely living 'off grid'. The problem arises when the temperature drops and heating is required. There is no way that a solar system and leisure battery will provide any meaningful heat in cold weather. 

I considered it, but decided against 'butchering' the van to install a fitted gas heater. I would firstly lose one of the very valuable cupboard spaces and I would have to cut both air and exhaust vents through the exterior, floor, or roof of the van. I did consider a Propex type blown air system which would involve only a few holes in the floor, but they are very, very expensive and consume a fair bit of power to power the fan. I also looked at the cheap Chinese diesel heaters, 'knock-offs' of the Eberspacher type cab heaters, but in addition to the cutting of holes in the van, they also need the fitting of a diesel tank somewhere in the van, and that it very limited in a Puck. I also read a lot that these heaters can also be quite noisy, and consume a fair amount of fuel.

After a fair bit of research, I opted for a gas Catalytic Heater, in particular an Alke Minicat. Popular with yacht and camper van users, particularly in the US, these are small, compact heaters which are either freestanding or wall mounted.

Being catalytic, these are flameless gas heaters. Heat is produced by the gas coming into contact with a catalytic mesh in the heater which creates heat. Being flameless, there is no carbon monoxide produced, but, the heater does consume oxygen and is is critical that there are fixed and open ventilation in the space being heated. In the case of my Puck, I have the model with a series of open vents at the base and top of the door, and I always leave the vents in the pop top open. The catalytic reaction does release some moisture, but with the extensive ventilation, I don't think that will be an issue.

The manufacturer instructions advise that the heater shouldn't be left unattended, ventilation must be maintained, and more interesting that because of the lack of moving parts and combustion, apart from visual inspection and periodic checks on leaks from joints etc., there is no maintenance required on the heater.

I got the heater from a yacht chandler and had to fit a hose and regulator. I opted for a quick release on the gas hose which would allow simple disconnection from the van gas when storing. I also use it connected to a bottle at home for a quick source of heat.

Also important is that the heater should be covered when cooled and not in use. The build up of dust or debris can present a risk of carbon monoxide if a significant build up is present when you ignite the heater.

I used it a few times at home to get used to the heater. The heater has a 'flame-out' safety shut off and it's a bit of faffing to get the heater going, but easy after a few attempts. After the gas is turned on, a small button is depressed for 20s, then a match or lighter placed through the grille near the element, then after ignition, the button is held another 30s before being released. The initial gas lighting operation heats the catalyst which allows the heat reaction to take place. Once 'alight', the fire glows very dimly (better seen in the dark), and is completely silent. It's 830W and has a good heat output. No heat adjustment, but it consumes a miserly 60g/h of gas.

Next came the arrangement for using it in the Puck. Although there is not fitted heater in my van, the Truma manifold below the sink had the heater valve fitted. The outlet has the standard Truma nut, and is blanked with a small bullet type blank. The manifold is designed for 8mm copper pipe, but special stepped 'olives' need to be used when running a gas pipe.

There is an existing hole between the manifold and the small cupboard where a factory fitted heater would have been installed. I used a pipe bender and ran a line through here, then fitted a compression hose connector, a length of hose, and the female end of the gas quick release where the male end of the connector on the heater connects.

I don't want to 'butcher' the cupboard door, so my intention is to position the heater in front of the slightly ajar door to allow the hose to exit. I intend to have it floor standing next to the door vents and I will assess it's performance on my next cold weather trip.

Depending on the heaters performance, I am considering removing the cupboard door, fitting another door with the heater mounted on it (effectively a 'winter' door) and a deflector to protect the doors above. I could then switch the doors whenever I need the heater. Floor mounted does allow for the heater to be moved or positioned for best effect.

I should add that for this kind of modification, I am a qualified and competent person for doing this kind of work, all fitting are new, and it was all leak checked.