Cruisers Forum
 


Join CruisersForum Today

Reply
 
Thread Tools Rate Thread Display Modes
Old 23-08-2007, 11:47   #1
Senior Cruiser
 
sneuman's Avatar

Cruisers Forum Supporter

Join Date: May 2003
Location: Jamaica
Boat: Tayana 37 Cutter
Posts: 3,167
Images: 37
Standard vs. tankless hot-water heater

I like the elegance of tankless hot-water heaters, but I gather the marine versions don't work as well as those use in homes.

Also, is there any reason to use a "marine" version (of either tankless or standard) instead of the smallest one I can find in Home Depot?
__________________

__________________
Voyage of Symbiosis: http://svsymbiosis.blogspot.com/
sneuman is offline   Reply With Quote
Old 23-08-2007, 12:43   #2
Senior Cruiser
 
SkiprJohn's Avatar

Cruisers Forum Supporter

Join Date: May 2006
Location: Kea'au, Big Island, Hawaii
Boat: Cascade, Sloop, 42 - "Casual"
Posts: 14,192
I just installed a Bosch tankless propane water heater at the house. What a dream. Instant hot water and doesn't require any electric hookups. I can't say what the difference would be for marine version or installation but I really do like the one I just got hooked up yesterday.
JohnL
__________________

__________________
SkiprJohn is offline   Reply With Quote
Old 23-08-2007, 13:40   #3
Senior Cruiser
 
Alan Wheeler's Avatar

Cruisers Forum Supporter

Join Date: Dec 2003
Location: Marlborough Sounds. New Zealand
Boat: Hartley Tahitian 45ft. Leisure Lady
Posts: 8,038
Images: 102
I don't think there is a difference (performance wise) than one for a house. I think the only major difference would be the way the gas is ignited. Marine ones are either battery or 12V. House ones will be mains operated. Apart from that, there are several sizes of califonts. I think the smallest is 5 or 6ltrs/mon and then there is a 10ltr and I have a 12ltr. They are rated at supposedly increasing the water temp by 25degC from the ambient temp at the rated flow. With 12ltr, I can turn the water flow down and have the water temp increase dramaticly. Danw can wash dishes (and she loves really hot water to do so) with water straight from the tap. WIth the smaller 5ltr unit, she could never get the water hot enough for her likeing. Of course, the bigger the unit, the more gas it will consume as well.
__________________
Wheels

For God so loved the world..........He didn't send a committee.
Alan Wheeler is offline   Reply With Quote
Old 23-08-2007, 13:50   #4
֍֎֍֎֍֎֍֎֍֎

Cruisers Forum Supporter

Join Date: Apr 2006
Posts: 13,042
The "marine" version might be built with different venting provisions, different CO protection and flame cut-off, different metals to resist salt air...or might just have a bigger price sticker and lower capacity per hour.

You'd have to compare units.
__________________
hellosailor is offline   Reply With Quote
Old 23-08-2007, 15:29   #5
Moderator Emeritus
 
Pblais's Avatar

Join Date: Mar 2003
Location: Hayes, VA
Boat: Gozzard 36
Posts: 8,700
Images: 15
Send a message via Skype™ to Pblais
We have a Bosch on Demand propane heater aboard. It's been with the boat since 1991. It works great. This is a ventless unit that has an Oxygen Depletion Sensor so it needs no outside vent or chimney. Most other units do need one so it is a nice feature if you can install it without a vent. That said I always open the port when using it as the heat is significant. This aids in drying out the shower / head since the unit is literally in the shower stall.

The unit has an inline shutoff for the propane so you can take it apart if need be. It seems to make enough hot water that you could drain the tank and still have warm water. That's probably the bad news as you really could take a very long shower until you ran out of water or propane. You can adjust the flow rate through the unit. On our water system at full force the water comes out pretty hot in the summer when the water temp in the tank is quite high but needs to be shut down in the late fall early spring when the water temperature is colder. On any boat water system it should work fine as you pressure is not as high as on land.

It turns the burner on and off as you open and close the valve so it is very economic on the propane.

The ignition is with a a push button pizeo button like you see an many house gas hot water heaters. You slide the button into light position, press the button and hold it then a thermocouple sets up so you can let go and slide into on position. the pilot light then remains on until you slide the button back to off. So you may light it for a period when all might use hot water then turn it totally off and shut the shutoff so no propane is on or can be turned on.
__________________
Paul Blais
s/v Bright Eyes Gozzard 36
37 15.7 N 76 28.9 W
Pblais is offline   Reply With Quote
Old 24-08-2007, 04:24   #6
Senior Cruiser
 
sneuman's Avatar

Cruisers Forum Supporter

Join Date: May 2003
Location: Jamaica
Boat: Tayana 37 Cutter
Posts: 3,167
Images: 37
Quote:
Originally Posted by Pblais
We have a Bosch on Demand propane heater aboard. It's been with the boat since 1991. It works great. This is a ventless unit that has an Oxygen Depletion Sensor so it needs no outside vent or chimney. Most other units do need one so it is a nice feature if you can install it without a vent. That said I always open the port when using it as the heat is significant. This aids in drying out the shower / head since the unit is literally in the shower stall.

The unit has an inline shutoff for the propane so you can take it apart if need be. It seems to make enough hot water that you could drain the tank and still have warm water. That's probably the bad news as you really could take a very long shower until you ran out of water or propane. You can adjust the flow rate through the unit. On our water system at full force the water comes out pretty hot in the summer when the water temp in the tank is quite high but needs to be shut down in the late fall early spring when the water temperature is colder. On any boat water system it should work fine as you pressure is not as high as on land.

It turns the burner on and off as you open and close the valve so it is very economic on the propane.

The ignition is with a a push button pizeo button like you see an many house gas hot water heaters. You slide the button into light position, press the button and hold it then a thermocouple sets up so you can let go and slide into on position. the pilot light then remains on until you slide the button back to off. So you may light it for a period when all might use hot water then turn it totally off and shut the shutoff so no propane is on or can be turned on.
paul,
which model do you own?
__________________

__________________
Voyage of Symbiosis: http://svsymbiosis.blogspot.com/
sneuman is offline   Reply With Quote
Reply

Thread Tools
Display Modes Rate This Thread
Rate This Thread:

Posting Rules
You may not post new threads
You may not 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 Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off


Similar Threads
Thread Thread Starter Forum Replies Last Post
Nigel Caulder on Hoses GordMay Construction, Maintenance & Refit 19 30-06-2015 13:14
Hot water is TOO hot. By Invitation Construction, Maintenance & Refit 10 18-08-2007 07:02
Hot Water Heater RETTSIE Plumbing Systems and Fixtures 1 05-07-2007 07:31
Perkin 4-108 hot water heater connections RETTSIE Construction, Maintenance & Refit 1 05-07-2007 07:04
Water Heater experience sought skipgundlach Product or Service Reviews & Evaluations 7 26-04-2007 06:13



Copyright 2002- Social Knowledge, LLC All Rights Reserved.

All times are GMT -7. The time now is 07:52.


Google+
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.
Social Knowledge Networks
Powered by vBulletin® Version 3.8.8 Beta 1
Copyright ©2000 - 2017, vBulletin Solutions, Inc.

ShowCase vBulletin Plugins by Drive Thru Online, Inc.