Diesel heater installation

[Tom Clay]

Jack,

I purchased the Espar through a company called cool-it in Canada. Link below.

http://www.cool-it.ca/ShoppingCart/.

They had a listing on Ebay for the Espar hydronic kit (18,000BTU). Included eveything except the through hole fitting, and the radiator's. I just checked Ebay and they have one listed for under $1200.00. Excellent service, we received the unit from Canada in 4 days. We also checked locally for the Espar and were quoted $2500-3500 for just the parts, $6000-7000 installed. We also heard we needed an additional pump, our system does not have one and functions fine. You will probably hear that the higher priced unit is designed for the marine environment, and the cheaper units are truck heaters. I checked the part numbers the heaters are same.

The 2 radiators I ordered locally from MSR marine. Call Jim at 206-546-5670. they were 135.00 each. He was also helpful in picking the right size heaters for the Catalina 34.
He recommended two smaller radiators, and he suggested we install them at the far ends of the main cabin. We did not plumb any heat into the cabins, as we like cooler sleeping. Through hole, plumbing and fittings added another $250-300.

The install was straight forward, and would not hesitate installing the Hydronic again. We spend alot of time on the hook and the wife wanted hot water. The radiator's have a 2 speed fan and on low they are verrrrry quiet.

I hope to be at the Catalina 34 get together next weekend, if you are coming maybe we can talk further.

[Jack Hutteball]

Thank you for the info Tom.

I have been checking around and found that Thermo King Northwest sells a "truck Kit" for $996 on special now.  I assume it may be similar to the package you have.  I need to see what it actually contains.  I reviewed installation manuals on line and noted that the unit is designed to be mounted on the outside frame rails of a truck, certainly a tougher environment than on our boats!

We plan on being at the meeting next weekend.  Hope to see you there and discuss your installation.

Jack

[Jack Hutteball]

Now that I am starting on my plumbing for a hydronic heating system I have a couple of questions.  I plan on hooking up the hot water heater and red dot heater that is already installed in the boat to the new heater system.  This loop comes off the engine with one connection on top of the fresh water pump and the other to the lower portion of the thermostat housing.

Is the supply the connection of this loop on the bottom of the thermostat and return to the top of the pump?

Second, after I disconnect these two lines and hook them into my heater loop, should the existing connections be capped or connected together with a small loop?

Jack

[Stu Jackson]

Jack,

1.  Looping the "old" connections from the fresh water pump to the hot water heater and back to the thermostat:  It sounds like you are planning to disconnect the engine cooling system from the hot water heater.  In Jim's August 2007 article, he wrote the following quoted below. 

I'm just wondering why you'd want to do that, because if you've been running your engine you won't have hot water.  You'd have to run the new diesel heater to get any hot water.  Means two "engines" have to run to get hot water if you're motoring.  My understanding is that most diesel heaters have the option of simply connecting into the existing cooling system.  I suggest you reconsider.

From Jim's article:

While the system installed in Windseeker provides only the hydronic space heating system, other system options are possible. In a truck application the DW4 typically provides standby engine heating as well as sleeper-cab heating so engine cooling system and Eberspacher hydronic systems are combined. This allows the truck engine to provide heat for the sleeper-cab while it is running and so long as truck engine coolant is over 160 F the DW4 never fires up. When the truck engine is shut down the DW4 takes over and keeps both engine and sleeper-cab warm.

"Thus by combining the diesel boat engine primary cooling system with the DW4 hydronic system it would be possible to alternately use engine heat for cabin heating or even provide domestic hot water as well as standby heat for the engine from the hydronic system. The DW4 SC manual provides plumbing instructions for these various schemes and Eberspacher offers the necessary sectionalizing and check valves to accomplish it."

2.  In or out for those two lines:  check your engine manual and on the manual section of our website.  There's a flow diagram showing the direction of flow in the Universal manuals.  The link to Marinedieseldirect finds this:  http://www.marinedieseldirect.com/universal/200157/universal-owners-manual-seawater-diagram.html

[Jack Hutteball]

Thanks Stu,
I read through the engine manual I have and it did not have that diagram.  Regarding leaving the existing heater/water heater connection to the engine and the new heater, the local espar marine dealer recommends against it for the reason that there are too many chances for leaks in the expanded system and potential for engine damage due to loss of coolant.  Their method is to introduce yet one more heat exchanger between the two systems to reduce the leak potential.  This requires that a separate circulation pump needs to be added into the loop that is not running, which adds too much complication.  However, every time a connection is made ie. even to a heat exchanger, there is a chance for a leak. 

While chasing down the current hose routing in the boat yesterday, I found a splice joint in the water heater loop where the red dot heater is connected that was leaking.  I have had a leak in the system since we bought the boat and almost had cured it by finding loose connections on the back of the water heater.  That fixed most of it, but taking more of the sink cabinet apart I was able to find this connection up under the refrigerator that I had not known about.

My preference is to hook both systems together so I have an either or option for hot water.  I truly is simple in a truck system.  So far I have seen no postings or talked to anyone who has actually done it.  I am going to pick up the heating unit this weekend and study the connection options that Jim talks about in his article.  As I have thought about how the water flows, it seems it would be simple to install a couple of "y" connectors and some check valves to connect the systems together.

Jack

[Craig Illman]

Stu & Jack - I think another reason to isolate the engine and heater coolant loops would be coolant longevity. I would think you'd rarely need to change the coolant in the heater loop, while the engine loop coolant should be replaced every couple years.

Craig

[Stu Jackson]

You both may remember my recent post about replacing the hot water hoses under the galley sole to the heater :  http://c34.org/bbs/index.php?topic=3769.0

I understand the issue regarding connections, and, like electrical, the less number of connections the better.  However, different than electrical, a simple way to check the coolant is to open the manifold cap and check the level on a regular basis.  A backup is the temperature alarm and temperature gage, not something I'd want to rely on because it'd be too late, but heck they're there.  Double clamping and proper design to minimize connections by sizing hoses between each POC would be the way to go.

As far as coolant, four to five years seems to be the recommended time for replacement, regardless of what service in which the coolant is used.  My experience has been that I end up doing it more often that I "need" to:  when the old alternator bracket broke I lost coolant; when the hoses to the HW heater under the galley sole broke, I lost coolant; when I remove my HX some of the coolant gets lost -- so changing it is not really much of a deal if you're working anywhere around the engine anyway! 

[Jack Hutteball]

Reading my engine manual yesterday I noted that they recommend changing coolant every 500 hours.  I just hit 400 so I have not worried about it yet, but may as well get to it while I am messing with the heater coolant.  My hoses at 6+ years should be good for a while.  Stu, the pictures of your old hose sure makes one want to keep track of hose condition.  It is a wonder you were keeping any coolant at all.

Jack