From most of the things I have found so far, it appears that the heater units are being fitted transversely.
Has anyone had an issue using them whilst moving?
Depends on what you mean by moving, during the season my boat spends much of its time on a swinging mooring where there can be a fair amount of movement from wind, weather and some inconsiderate ‘erberts who ignore the harbour rules requiring a speed of no more than dead slow while in the vicinity of the moorings. During those times my heater has performed as faultlessly as it has at all other times when in use, and that’s over the almost nine years I’ve had the boat. During that time I’ve not done anything by way of servicing the machine, an Ebberspacher, and I don’t suppose the boats previous owner, a charter firm, did anything either.
I’ve never run the heater while the boat was at sea, mainly because my crew and I were mostly outside in the cockpit area and dressed for whatever the weather was doing at the time, and so didn’t need being heated.
The Ebberspacher is mounted transversely within the lazarette, and is secured to the port aft cabin bulkhead (my boat, a B36 2002), has three sleeping cabins plus a main saloon and a forward port side heads compartment. The exhaust passes out through the hull port side a short distance more or less above the engine exhaust. The heater ducts, uninsulated when I bought the boat, but now mostly insulated with some stuff a seller referred to as “thinsulate,” but which I’m not so sure about, run forward just to port of the centreline and below the level the bed base in the aft port cabin. On reaching the vicinity of the engine compartment, there is a branch which supplies a closeable swivel outlet into the port aft cabin. The main duct also turns across to the starboard aft cabin where it supplies warm air to another branch serving that cabin. From there the main duct turns forward again but along the starboard side, to the main saloon where it serves a third and final outlet into the saloon. That outlet is at the bottom of the seat provided in way of the chart desk. All heater outlets have a directional and closeable fitting, but there are only three of them which means that there is no heater outlet in either the forward cabin or the heads compartment, but those areas warm quite quickly, even in the depths of a North Wales winter which rarely gets desperately cold on account of the Gulf Stream. Arguably I need a more powerful heater, and I’ve forgotten what the output capacity of the heater is, but as I said earlier it doesn’t take long to warm the boat sufficiently for it to be comfortable.
Wrapping the so called “thinsulate” around the main heater duct has served several purposes, initially it stops much of the heat loss to the lazarette and also to the under bunk areas of the two aft cabins, also conversely this has increased the temperature within the main cabin quite significantly. This has a
further benefit in that the heater doesn’t use quite so much diesel fuel as it might otherwise have done.
At sometime in the future I might be inclined to extend the heater ducting to the forward cabin and to the heads, but in all honesty, I don’t think it actually matters at the moment