I am now into year four aboard with the Espar. I can report that the Espar has worked without a hitch. One dirty fuel filter and that was maintainance. You want heat, you got heat. No fuss no muss, and enough that cold is a word you can forget.

Defiance Heating Costs

All 12 & 24 volt systems are new state of the art. But, it is heat is what sets this boat apart. There is a Espar Hydronic 35, 35,000 BTU central heating system, combined with a wood stove provide every heating option you could imagine. Even in -40 all you need do is kick in the Espar and you have no idea what the temperature is outside.

When I first planned to return to living aboard my boat year round the primary concern was strength and warm. The following is the end solution to this criteria. After much research the only marine grade furnace made specifically for Arctic like conditions was the ESPAR 35 Hydronic unit. Also said up front, trying to put central heating like this in a 42' boat is extremely difficult as everywhere you turn around is 1/4" steel.

Finally after 3 days of trying they got the exhaust fitted after another 2 hour battle with the remains of the Lister. The Lister is non-functioning get home engine of 1945 "D" Day technology.. Perhaps it was  good choice in 1971 but today  the  engines 2,500 lbs weight and massive size  that only  produces 18 horsepower, when it was working, is a waste of time. Its  exhaust was the first option considered in the Espar install, but on inspection it proved to be 100% rotten.  Next they had to deal with the asbestos removal because all the old exhaust vent loops were deeply covered in a  3 to 4' wrapping of asbestos.

The intake passage is also 3" diameter passages with very exact tolerances and lengths in order for the ESPAR to work right. To run the air intake ESPAR allows a distance of ..... feet of supplied intake duct. However the installer need to be pretty good on math as the "brain" senses intake pressure within it's fail safe protocols.

To archive the correct tuning there is a desired length to free air of ...... feet. The fitter must calculate other factors which effect the air flow such as restrictions in the passage as each change in flow creates a corresponding pressure effect. A 80 degree elbow adds the equivalent of another 5' length to the intake pressure which must be exact. If the Espar "brain"  computer monitors everything, automatically   shuts down if something is not right.

The Install

Follow the steps required to fit Defiance with the heating system below.

The engine room is set below the pilot house and has roughly 6V of headroom and extends full width to the exterior hull aft of the fuel tanks, and obstructed by fuel tanks to the forward half.

Power requirement for the 2004 refit have drastically decreased the amount of space available below deck aboard making the entire project a huge jig saw puzzle.

General space usage in the engine room is allocated with 16 deep cycle 6V banks of batteries made up of: 2 group 31a for engine/generator starting, a Xantrex 12 VDC 60 AMP charger, Heart 24 VDC charger/5K inverter, the generator and charging systems.

Seen here on the aft deck just prior to installation the is the ESPAR boiler and Pat's fabricated distribution manifolds.

The heart of the Espar is the Oil fired burner which amazingly produces 120,000 BTU burning 0.75 gallons of diesel an hour when engaged.

Seen closer in this image the "turbulator" is a careful sculpted plate that swirls the atomized fuel into the burn chamber effectively greatly increasing the efficiency

With the starboard side of the primary engine full, only the port offered available space to install the ESPAR and its distribution systems

Of course, any and everything on a boat is difficult to get to and the only practical location on board this boat was a special lesson in awkwardness.The final resting place for the ESPAR is tucked at the absolute aft end of the engine room on the port side the available nook was guarded by the now extinct Lister "get home" or "pup" engine.

The first step was removing as much of the Lister engine and it's accessories as was possible to make space to work. Pat spent days in the hole with a saws all and other tools cutting and clawing back the required in square inches of volume to fit everything.

After several days of demolition followed by fabrication the Espar was mounted in position. You can see the remains of the Lister exhaust just behind the Espar, against the hull.

In order for the glycol solution to circulate correctly the flow must be delivered equally to each of the registers. This is accomplished by constructing a custom manifold from copper for both inlet and outlet legs of the system.

There was never a simple place to get to, but got it was.

There are two manifolds that distribute the glycol water mix to the radiators in the cabins. One is outgoing hot fluid the other is the return line.

The radiators are connected via a hi-tech plastic tubing called "K-Pec" which uses special fittings to attach to the threaded connections.

As with every insulation there are always inspectors. Cat is very particular when people go around cutting into the surroundings. He is not quite positive he likes the changes. However knowing cats and their little "warm button" portion of cat brain he will be OK once it starts to make heat.

It is a good thing that Defiance has such a workable engine room. You can see in the picture to the left the K-Pec lines snake aft over the Lister and dive gently down beside the transmission for assess to the aft cabin. Even the lines running to the starboard salon rad are no problem in the finished engine room configuration.

The manifold is connected to the K-Pec. Note the neat little compression fittings, at $34 per fitting. But they work and nothing has ever let go even when running.

Seen here the small Heater Craft stainless steel radiator is installed below the V berth.

The Espar can be reached for maintenance with a little wiggling and it is not bad at all to change a fuel filter or make an adjustment to the fuel air mix.