Date   

engine exhaust high temp alarm Sea Chest Clog Alarm

eric freedman
 

Hi Bill,

This has saved my bacon twice. I mounted it by the Amel name plate on the companionway.

http://www.borelmfg.com/products_alarm.htm

 

Fair Winds

Eric

Amel Super Maramu #376

 

 

From: main@AmelYachtOwners.groups.io [mailto:main@AmelYachtOwners.groups.io] On Behalf Of Karen Smith via groups.io
Sent: Sunday, November 29, 2020 9:18 AM
To: main@AmelYachtOwners.groups.io
Subject: Re: [AmelYachtOwners] Sea Chest Clog Alarm

 

Thanks, all!  

I was not looking to install one, just get a feel for the setpoint.  A minimum setpoint of -200 mbar gauge (80 inches of water) tells me what I need to know.  That's a significantly higher vacuum setpoint than I expected.  I would have thought something like 20 instead of 200.

For our raw water system, (which is a lot simpler than a later model SM) the AC units quickly shut down on high pressure if there is insufficient water, the genset quickly shuts down on high exhaust temperature if it lacks water. Adding a high wet exhaust temperature alarm to the main drive engine will cover pretty much all the cases.

Bill Kinney
SM160, Harmonie
Fort Lauderdale, FL, USA


Re: Sea Chest Clog Alarm

Karen Smith
 

Thanks, all!  

I was not looking to install one, just get a feel for the setpoint.  A minimum setpoint of -200 mbar gauge (80 inches of water) tells me what I need to know.  That's a significantly higher vacuum setpoint than I expected.  I would have thought something like 20 instead of 200.

For our raw water system, (which is a lot simpler than a later model SM) the AC units quickly shut down on high pressure if there is insufficient water, the genset quickly shuts down on high exhaust temperature if it lacks water. Adding a high wet exhaust temperature alarm to the main drive engine will cover pretty much all the cases.

Bill Kinney
SM160, Harmonie
Fort Lauderdale, FL, USA


Re: Sea Chest Clog Alarm

Roque
 

Karen,

I just ordered mine from Amel, $60,62 euros each, adaptor included (ex-Vat & shipping). Hasn't arrived yet. 

As far as I know, they are are made by Elettrotec – Italy (http://www.elettrotec.com/US/Vacuum_Switches.asp).

The adjustable pressure range (Elettrotec), depending on the model, is from  -200 to -900 mbar. 

Roque
Attika A54 # 117
Paraty- Brazil


Re: Timer for autmatic watermaker flush

eric freedman
 

Hi Mark,

Thank You,

I did not see the spec sheet before.

 

That will work nicely. I just have to remember to turn it off when I am on board.

Fair Winds

Eric

Amel Super Maramu #376

 

 

From: main@AmelYachtOwners.groups.io [mailto:main@AmelYachtOwners.groups.io] On Behalf Of Mark McGovern
Sent: Saturday, November 28, 2020 5:43 PM
To: main@AmelYachtOwners.groups.io
Subject: Re: [AmelYachtOwners] Timer for autmatic watermaker flush

 

Eric,

I didn't really see it specified anywhere in the eBay listing but if you scroll through the pictures you will see a schematic showing a 16amp switch.  It also looks to be identical to this timer sold on Amazon that states that it is has a 16amp switch:  https://www.amazon.com/Baomain-CN101-Digital-Programmable-Switch/dp/B01MRYMT3H/ref=sr_1_9?dchild=1&keywords=24vdc+timer&qid=1606595869&sr=8-9


--
Mark McGovern
SM #440 Cara
Deale, MD USA


Re: Timer for autmatic watermaker flush

Mark McGovern
 

Eric,

I didn't really see it specified anywhere in the eBay listing but if you scroll through the pictures you will see a schematic showing a 16amp switch.  It also looks to be identical to this timer sold on Amazon that states that it is has a 16amp switch:  https://www.amazon.com/Baomain-CN101-Digital-Programmable-Switch/dp/B01MRYMT3H/ref=sr_1_9?dchild=1&keywords=24vdc+timer&qid=1606595869&sr=8-9


--
Mark McGovern
SM #440 Cara
Deale, MD USA


Re: Timer for autmatic watermaker flush

eric freedman
 

Hi Mark,

Where did you find the Amp rating?

Fair Winds

Eric

Amel Super Maramu #376

 

 

From: main@AmelYachtOwners.groups.io [mailto:main@AmelYachtOwners.groups.io] On Behalf Of Mark McGovern
Sent: Saturday, November 28, 2020 3:55 PM
To: main@AmelYachtOwners.groups.io
Subject: Re: [AmelYachtOwners] Timer for autmatic watermaker flush

 

Eric,

It's appears to have a 16amp switch but you never really know with a ~$9 eBay timer.  If you are concerned, you could always have the timer control a relay and have the relay control the pump.

--
Mark McGovern
SM #440 Cara
Deale, MD USA


Re: Timer for autmatic watermaker flush

Mark McGovern
 

Eric,

It's appears to have a 16amp switch but you never really know with a ~$9 eBay timer.  If you are concerned, you could always have the timer control a relay and have the relay control the pump.

--
Mark McGovern
SM #440 Cara
Deale, MD USA


Re: Timer for autmatic watermaker flush

eric freedman
 

Hi Mark,

I was just thinking of running a additional wire to the hot side of the fresh water  pump, with a switch in the circuit.

I would leave the pump circuit breaker off and when the timer is activated it would run the pump for a few minutes. My only concern is, can the timer carry the current needed for the pump.

Fair Winds

Eric

Amel Super Maramu #376

 

 

From: main@AmelYachtOwners.groups.io [mailto:main@AmelYachtOwners.groups.io] On Behalf Of Mark McGovern
Sent: Saturday, November 28, 2020 2:16 PM
To: main@AmelYachtOwners.groups.io
Subject: Re: [AmelYachtOwners] Timer for autmatic watermaker flush

 

Eric,

This programmable timer is very similar if not identical to the one that Bill Rouse has posted about using for this purpose:  http://www.ebay.com/itm/224040425984

You also need a 24vdc solenoid like this one for the timer to control the flow of freshwater:  https://www.burkert-usa.com/en/products/solenoid-valves/water-solenoid-valves/221602  

--
Mark McGovern
SM #440 Cara
Deale, MD USA


Re: Timer for autmatic watermaker flush

 

Yes, and let me add a warning about a potential mistake...I made it when I first did this.

Mark McGovern is correct about the solenoid that he says I used, but it was not the first one I used. The first one I used was indeed 24 volts, but AC rather than DC voltage. There are many 24VAC solenoid water valves available because this is what many lawn sprinkler systems use. And that is what I used until it failed about 2-3 months later. Be sure to check for DC Voltage:
image.png
CW Bill Rouse Amel Owners Yacht School
Address: 720 Winnie, Galveston Island, Texas 77550 
View My Training Calendar


On Sat, Nov 28, 2020 at 1:16 PM Mark McGovern <mfmcgovern@...> wrote:
Eric,

This programmable timer is very similar if not identical to the one that Bill Rouse has posted about using for this purpose:  http://www.ebay.com/itm/224040425984

You also need a 24vdc solenoid like this one for the timer to control the flow of freshwater:  https://www.burkert-usa.com/en/products/solenoid-valves/water-solenoid-valves/221602  

--
Mark McGovern
SM #440 Cara
Deale, MD USA


Re: Timer for autmatic watermaker flush

Mark McGovern
 

Eric,

This programmable timer is very similar if not identical to the one that Bill Rouse has posted about using for this purpose:  http://www.ebay.com/itm/224040425984

You also need a 24vdc solenoid like this one for the timer to control the flow of freshwater:  https://www.burkert-usa.com/en/products/solenoid-valves/water-solenoid-valves/221602  

--
Mark McGovern
SM #440 Cara
Deale, MD USA


Re: Sea Chest Clog Alarm

 

Karen,

I do not have the precise vacuum, but I imagine that Amel probably adjusts the vacuum switch when it is installed. Here is the information I have in my book. The source of this information was Amel:
The Amel Sea Chest has an Amel innovative Vacuum Switch attached
via a hose to the Sea Chest Manifold. The Vacuum Switch is located
above the sea chest. Sea Chest blockage will create suction inside the
Sea Chest, which closes the switch, activating an alarm. Test this alarm
switch by closing the Sea Chest valve for up to 8 seconds while the engine
is running.

The internal part of the switch can get clogged as well as the curved
copper pipe. If the alarm isn't working, check for clogs.
To adjust the sensitivity of the vacuum switch, remove the top screw, then
using a jeweler's flat head screwdriver, inserted into a tiny, concealed
adjuster screw adjust the sensitivity. Turning the small screw clockwise,
increases sensitivity and the alarm comes on. Anticlockwise and the alarm
stops. Through trial and error, you will find the ‘sweet spot’ by running
the fridges, AC, engine, and generator at the same time. NOTE:
Adjusting sensitivity doesn't require the removal of the Vacuum Switch.

image.png

Also, if you order the sensor from Amel and have the one below on the left, you will find it has changed to the one below on the right.
image.png
CW Bill Rouse Amel Owners Yacht School
Address: 720 Winnie, Galveston Island, Texas 77550 
View My Training Calendar


On Sat, Nov 28, 2020 at 5:18 AM Alan Grayson <bazgrayson@...> wrote:
I believe it is a vacuum activated switch as I remember doing to some work on the A/C unit that required the seacock to be closed. When I fired it back up with the sea cock closed it activated pretty much straight away

From: main@AmelYachtOwners.groups.io <main@AmelYachtOwners.groups.io> on behalf of Karen Smith via groups.io <karenharmonie=yahoo.com@groups.io>
Sent: Saturday, 28 November 2020 3:24 AM
To: main@AmelYachtOwners.groups.io <main@AmelYachtOwners.groups.io>
Subject: [AmelYachtOwners] Sea Chest Clog Alarm
 
Those of you who have a newer SM with the switch that triggers the alarm for a clogged seachest:  

Does anybody know the pressure setpoint of this switch?


Timer for autmatic watermaker flush

eric freedman
 

Hi,

Some of you use a timer to activate the flush mechanism for the watermaker.

What model unit do you use?

Fair Winds

Eric

Amel Super Maramu #376

 


Re: Sea Chest

Patrick McAneny
 

Bill, While sailing back from Bermuda on a starboard tack ,my gen set shut down several times,I found that there was no water in the strainer,taking off the cap allowed it to fill. What do you think about inserting a very small tube in the lid and run  it up under the cockpit floor ,maybe with a one way valve ,so that an air lock would not form. Just a thought.
Pat
SM #123


-----Original Message-----
From: Karen Smith via groups.io <karenharmonie@...>
To: main@AmelYachtOwners.groups.io
Sent: Fri, Nov 27, 2020 4:34 pm
Subject: Re: [AmelYachtOwners] Sea Chest

Chris,

I have taken the photos and annotated them with the parts list.  

All of the fittings I used are standard NPT pipe fittings.  In the case of the outlet fitting on the strainer, that is actually a female 1-1/2” BSP thread.  In this size, the NPT and BSP threads are compatible enough that they will screw together just fine, but they will not make a reliable high pressure seal.  Don’t expect “teflon tape” to help here.  You’ll need paste type pipe sealant.  For the very low pressures seen here, it works fine despite the small mismatch in thread shapes..

We have been running this long enough now, we can confidently say that it works with no issues. Well, no issues that were not already there with the stock Amel manifold.

Here is the only problem we have with the “sea chest” design.  As we sail, air is entrained under the hull.  Some of this air finds the sea chest thruhull and rises into it, displacing the water.  If we are sailing fast, enough air comes through that in a very few hours the strainer and standpipe are empty of water. I am pretty confident that needing to purge this entrained air is the primary reason that the generators on Amel’s have such short lived raw water impellers.  I have a couple of ideas on how to improve this situation, but nothing ready to implement yet.

Our new generator has a hair trigger on its exhaust temperature shutdown which has made this problem more obvious.  Occasionally, and only when we are sailing, the high exhaust temp triggers a shut down right after it starts.  A second start try and it runs fine. If I crack the lid of the strainer and purge the air, it never happens. 

Short of closing the sea cock, I can’t think of a way to keep the air out, so I am trying to figure out a way to easily purge it.

Bill Kinney
SM160, Harmonie
Fort Lauderdale, FL, USA



Re: Sea Chest Clog Alarm

Alan Grayson
 

I believe it is a vacuum activated switch as I remember doing to some work on the A/C unit that required the seacock to be closed. When I fired it back up with the sea cock closed it activated pretty much straight away


From: main@AmelYachtOwners.groups.io <main@AmelYachtOwners.groups.io> on behalf of Karen Smith via groups.io <karenharmonie@...>
Sent: Saturday, 28 November 2020 3:24 AM
To: main@AmelYachtOwners.groups.io <main@AmelYachtOwners.groups.io>
Subject: [AmelYachtOwners] Sea Chest Clog Alarm
 
Those of you who have a newer SM with the switch that triggers the alarm for a clogged seachest:  

Does anybody know the pressure setpoint of this switch?


Re: Sea Chest

Clive Chapman
 

Would an automatic vent from a central heating system help? Something like this: https://www.toolstation.com/reliance-automatic-air-vent-push-fit/p74735

Would need to find one that is seawater safe. 


Re: Sea Chest

Karen Smith
 

Matt, 

Obviously great minds think alike. That is the approach I am most seriously considering. The devil is in the details but I’m thinking it’s the right direction to go.

Bill Kinney
sm160, Harmonie
Fort Lauderdale, FL, USA


Re: Sea Chest

Matt Salatino
 

How about a vent hose that ends high in the engine room, close to deck level, centered in the boat? This would allow the water level to stay at outside sea level.

~~~⛵️~~~Matt

On Nov 27, 2020, at 10:21 PM, Karen Smith via groups.io <karenharmonie@...> wrote:

Mark,

That certainly addresses the problem of air in the seachest. Unfortunately, those of us with older SM models don't have that option since the washdown pump does not draw its water from the seachest.

Adding an "extra" pump just to suck out the air is one option, but seems to me a very inelegant one.

Bill Kinney
SM160, Harmonie
Fort Lauderdale, FL, USA


Sea Chest Clog Alarm

Karen Smith
 

Those of you who have a newer SM with the switch that triggers the alarm for a clogged seachest:  

Does anybody know the pressure setpoint of this switch?


Re: Sea Chest

Karen Smith
 

Mark,

That certainly addresses the problem of air in the seachest. Unfortunately, those of us with older SM models don't have that option since the washdown pump does not draw its water from the seachest.

Adding an "extra" pump just to suck out the air is one option, but seems to me a very inelegant one.

Bill Kinney
SM160, Harmonie
Fort Lauderdale, FL, USA


Re: Sea Chest

Thomas Peacock
 

Thanks as always for the tips, Bill.

On the short life of the generator impeller, I have much experience, and a tiny bit of advice.

After we bought our boat about ten years ago, the generator would go through impellers every 15 or 20 hours, obviously a major pain.

When in Martinique, I had Didiere, the local, very experienced diesel mechanic, work on a separate issue. He always looked into the impeller problem, and put a new one in, using some sort of glue-type substance on the Woodruff key that keeps the impeller working correctly. The new impeller lasted only about three hours. (That said, I still think Didiere is a great mechanic).

For the next one, I did three things:

1. I also put a mild glue on the Woodruff key

2. I sanded the inner part of the impeller housing (perhaps the metal is more prone to accumulating residue from the rubber, which then leads to excessive friction)

3. I lubricated the inner housing with Molykote. 

Since, then, I have had no impeller problems, 

Might be coincidence, but it works for me.

Tom Peacock
SM 240 Aletes
Chesapeake Bay, awaiting vaccine


On Nov 27, 2020, at 4:34 PM, Karen Smith via groups.io <karenharmonie@...> wrote:

Chris,

I have taken the photos and annotated them with the parts list.  

All of the fittings I used are standard NPT pipe fittings.  In the case of the outlet fitting on the strainer, that is actually a female 1-1/2” BSP thread.  In this size, the NPT and BSP threads are compatible enough that they will screw together just fine, but they will not make a reliable high pressure seal.  Don’t expect “teflon tape” to help here.  You’ll need paste type pipe sealant.  For the very low pressures seen here, it works fine despite the small mismatch in thread shapes..

We have been running this long enough now, we can confidently say that it works with no issues. Well, no issues that were not already there with the stock Amel manifold.

Here is the only problem we have with the “sea chest” design.  As we sail, air is entrained under the hull.  Some of this air finds the sea chest thruhull and rises into it, displacing the water.  If we are sailing fast, enough air comes through that in a very few hours the strainer and standpipe are empty of water. I am pretty confident that needing to purge this entrained air is the primary reason that the generators on Amel’s have such short lived raw water impellers.  I have a couple of ideas on how to improve this situation, but nothing ready to implement yet.

Our new generator has a hair trigger on its exhaust temperature shutdown which has made this problem more obvious.  Occasionally, and only when we are sailing, the high exhaust temp triggers a shut down right after it starts.  A second start try and it runs fine. If I crack the lid of the strainer and purge the air, it never happens. 

Short of closing the sea cock, I can’t think of a way to keep the air out, so I am trying to figure out a way to easily purge it.

Bill Kinney
SM160, Harmonie
Fort Lauderdale, FL, USA


<9495D3AA-FC12-427B-AD1A-C082BAE84D49.jpeg><288A2531-8543-43CF-91FA-F8D6F4D69446.jpeg>


--
Tom Peacock
SM 240 Aletes
Chesapeake Bay