Connecting Raritan Water Heater to Engine

[edwmama]

ahoy mates

I have a 12 gallon raritan water heater in my Cal Cruising 46, and I would like to connect it to the engine's cooling-heat exchanger.
the boat has a spacious engine room which contains the Perkins 4.236.

my question is
1) is this advisable to connect the water heater to the engines heatexch?

2) what are the common problems that arise out of this configuration?

3) will this compromise in anyway the perkins cooling system

4) will affect the longevity of my raritan wwater heater (built in mid 80's?)


please reply privately edwmama AT yahoo DOT com or here

bests
edwin

[svHyLyte]

The water heater will have no adverse effect on your engine's cooling system. Everything you need to know appears at http://www.raritaneng.com/pdf_files/...eaterv0502.pdf

[edwmama]

Thx for the reply
I actually have that sMe article you have sent
I was hoping for candid comments on field experience from various sailors

I appreciate your helpful reply

edwmama

[David M]

I used to have a hot water heater that had engine coolant running through it. I currently have a cabin heater that does the same. I have experienced no problems doing this. You just have to make certain it is plumbed correctly and reliably which includes shut off valves rigidly plumbed to the engine on both the inlet and outlet sides in case you have a leak or a burst.

The engine manufacturer will know where you are supposed to take the coolant from and return it to the engine. Te heat exchanger may not necessarily be where you attach the lines to. The supply side to the heater is more likely to be close to the pressure side of the coolant circ pump and the opposite for the return line.

[AnchorageGuy]

Our hot water heater was plumbed to our 4-108 and traveled thousands of miles and hundreds of hours. The current boat has a Ford-Lehman with the HW heater plumbed in and works fine. There are more boats with this type system than without, I would guess.

[svHyLyte]

Originally Posted by edwmama

Thx for the reply
I actually have that sMe article you have sent
I was hoping for candid comments on field experience from various sailors

I appreciate your helpful reply

edwmama

We have the same Raritan water heater plumbed to the cooling system on our Perkins 4-108. The system has a "by-pass" loop such that one can moderate the flow rate through the water heater and thus the termperature of the water to the galley and heads (our engine's normal operating temperature is much too hot for the domestic water supply) . Like David, above, we also have a cabin heater plumbed into our system--with cut-off valves--so that we can heat the boat during the winter months. Both the water heater and the cabin heater work very well and have no adverse effect on the engine. While its not relevant to your specific question, if you're going to be working on your water heater, you might want to investigate the condition of the annode which is a part of the hot water discharge valve assembly. They need to be replaced, and the tank thoroughly flushed and cleaned, at roughly 3-5 year intervals.

FWIW...

[edwmama]

Thanks David M and Fwiw

I will look into this loop that would regulate flow so as not to overheat the water. Incidentally my boat came with a proheat cabin heater
that was 1/5 installed, meaning no piping connection and no connection to the engine. It looks like the the water heater coolant in and coolant out are somehow connected to this proheat system which apparently is commoly used by 18 wheeler trucks used in Canada to heat the little driver
cabin. I am debating whether I should continue and complete this
seeminly exhaustive and complicated installation

I just want something more simple diesel heater that can run without relying on the engine to be running to get heat

this proheat seems very complex thus more things to breakdown

Thoughts?

[osirissail]

That Raritan discussion of engine coolant is not very advisable. You do not want to put a valve in a system that shuts off the coolant from the engine to the engine heat exchanger. What is better is to have ball valves in the supply and return hoses of the water heater.
- - The supply hose to the water heater comes off the outlet of the engine coolant water pump. Perkins actually have an additional "plug" in the outlet of the water pump for attaching the line to the water heater. The return line from the water heater can be attached to another provided hose plug in the cylinder head.
- - In essence you have two heat exchangers: first the normal one and secondly the water heater. Opening the water heater coolant line ball valves allows the hot coolant from the engine cooling water pump to pressurize and send hot engine coolant to the hot water heater which then returns to the engine.
- - Should a hot water heater hose leak or burst you can shut both ball valves and maintain the integrity of the original heat exchanger system on the engine. Partially opening or closing the supply line valve to the water heater regulates how much hot coolant is sent to the water heater.
- - Good quality stainless steel ball valves work great and stay operational better than brass/bronze valves.

[edwmama]

Thx for a very informatve points