SailNet Community - Reply to Topic
Thread: Water Heater By Pass Valve Reply to Thread
Send Trackbacks to (Separate multiple URLs with spaces) :
Post Icons
You may choose an icon for your message from the following list:

Register Now

In order to be able to post messages on the SailNet Community forums, you must first register.
Please enter your desired user name, your email address and other required details in the form below.
Please note: After entering 3 characters a list of Usernames already in use will appear and the list will disappear once a valid Username is entered.

User Name:
Please enter a password for your user account. Note that passwords are case-sensitive.


Confirm Password:
Email Address
Please enter a valid email address for yourself.

Email Address:


Human Verification

In order to verify that you are a human and not a spam bot, please enter the answer into the following box below based on the instructions contained in the graphic.

  Additional Options
Miscellaneous Options

Click here to view the posting rules you are bound to when clicking the
'Submit Reply' button below

  Topic Review (Newest First)
10-31-2002 09:41 AM
Water Heater By Pass Valve

Please understand that I do not advocate the bypass valve scheme required when the water heater is in series with the heat exchanger. Also pleas understand that the engine manufacturers now recommend the use of the thermostat bypass circuit for the water heater. see to look at the different options.
10-28-2002 08:36 AM
Water Heater By Pass Valve

I''m just about to put my water heater in series with my engine and thermostat. I have a Yanmar 3QM30F. Do you have a drawing on how you did yours with the by-pass. On my yanmar the distance between the eng. and thermostat is only about 4".
Chuck -SV Sirena
10-26-2002 08:30 AM
Water Heater By Pass Valve

A Catalina 38 owner sent in a picture of his by pass valve installation and
it is on the following web page:

He reports about 7.5 knots using a 16 inch, feathering Max-Prop
set for # 16 in the Max-Prop book. As of 24 Oct he was not
sure the valve was open or closed, but he never overheated.

A Catalina 36 owner posted the following well written summary on Oct 14, 02:

> Short story: With the water heater removed the engine will stay
> _exactly_ at the thermostat setting even at full throttle.
> Since I changed to a larger prop, my M25 engine became cooling
> limited. That is I had to reduce the RPMs or the engine would
> eventually (after about an hour) over heat. With the old 15x11
> fixed prop I did not have a cooling problem but with the 16x11
> folding prop I do.
> Easy fix. I opened the heater by-pass valve. I have a 160F
> thermostat installed and with the bypass valve open the engine
> will not heat about 160 even at 90% throttle for an hour.
> I was able to do a pretty conclusive test as I had to motor in
> dead calm at 8:00am to a race start.
> What this proves to me is that having a water heater plumbed in line
> with the engine coolant greatly reduces the engine''s cooling
> ability by slowing the coolant flow through the engine and the
> heat exchanger. With the bypass valve I can switch the water heater
> in and out of the loop in a second by turning a 3/4" ball valve
> handle and can see the effect quickly

Posting Rules  
You may post new threads
You may post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is On

For the best viewing experience please update your browser to Google Chrome