Topics

Hot water pressure

Mawgan grace
 

Hi all,

I’ve just replaced my hot water heater and I’ve got no hot water pressure! Cold water is great with the pump cutting in and out but the hot water is a dribble. I’ve checked no air locks etc.. any ideas?

regards

Mawgan

SV Adela #310 SM

 

You didn't say, but the obvious would be that you mixed up the connections between the engine and the the water system. This is easy to do, especially because the orientation of these connection change between different model heaters. If, you have the above issue, you likely have some engine coolant inside the hot water lines and will need to completely flush it out. 

Additionally, I have seen the copper Amel-made connection elbows become completely clogged. This is easy to see and clean. 

I hope this helps you. 

Best,

CW Bill Rouse
Yacht School - Supporting Amel Owners
www.YachtSchool.us
720 Winnie St
Galveston Island, TX 77550
+1(832) 380-4970

On Sat, Jul 13, 2019, 12:39 AM Mawgan grace via Groups.Io <gashman=ymail.com@groups.io> wrote:
Hi all,

I’ve just replaced my hot water heater and I’ve got no hot water pressure! Cold water is great with the pump cutting in and out but the hot water is a dribble. I’ve checked no air locks etc.. any ideas?

regards

Mawgan

SV Adela #310 SM

Thomas Kleman
 

On my basic 40 the pressure relief valve is constantly tripping (especially when water is heated by running engine). Also the sealing o-ring can deform and block part of the flow. I'd check those things too.

 

Thomas,

You should have an accumulator tank installed in the hot water circuit near the water heater. This will accommodate the increase pressure when the main engine reaches an operating temperature of 80C. The rubber bladder inside the accumulator tank may be defective. When the accumulator tank bladder leaks, the accumulator tank can no longer function. You should check for this.  If the accumulator tank  has been removed, you should replace it.

If you have an accumulator tank  and the bladder is OK, the next time the relief valve opens, measure the temperature of the engine at the coolant water pump or the oil filter. It should be 80C after the engine has been running for 1 hour in normal weather conditions. If it is higher than 8%, you may have an issue with your engine.

I hope that this helps you and others with this issue.

Best,

CW Bill Rouse
720 Winnie St
Galveston Island, TX 77550
+1(832) 380-4970



On Sat, Jul 13, 2019 at 8:45 AM Thomas Kleman <lorient422@...> wrote:
On my basic 40 the pressure relief valve is constantly tripping (especially when water is heated by running engine). Also the sealing o-ring can deform and block part of the flow. I'd check those things too.

michael winand
 

On a brand new water heater they have a plastic plug in the connections. This may have been pushed into the connection. This can happen in transit. 

On Sun, 14 Jul 2019 at 2:42 am, CW Bill Rouse
<brouse@...> wrote:
Thomas,

You should have an accumulator tank installed in the hot water circuit near the water heater. This will accommodate the increase pressure when the main engine reaches an operating temperature of 80C. The rubber bladder inside the accumulator tank may be defective. When the accumulator tank bladder leaks, the accumulator tank can no longer function. You should check for this.  If the accumulator tank  has been removed, you should replace it.

If you have an accumulator tank  and the bladder is OK, the next time the relief valve opens, measure the temperature of the engine at the coolant water pump or the oil filter. It should be 80C after the engine has been running for 1 hour in normal weather conditions. If it is higher than 8%, you may have an issue with your engine.

I hope that this helps you and others with this issue.

Best,

CW Bill Rouse
720 Winnie St
Galveston Island, TX 77550
+1(832) 380-4970



On Sat, Jul 13, 2019 at 8:45 AM Thomas Kleman <lorient422@...> wrote:
On my basic 40 the pressure relief valve is constantly tripping (especially when water is heated by running engine). Also the sealing o-ring can deform and block part of the flow. I'd check those things too.

Thomas Kleman
 

Bill- I definitely have no accumulator tank in the circuit. I just thought all these years that the basic 40 had a relief valve set too low (7 bar ?). These relief valves tend to last me 1-2 years (I buy them in bulk). Can you send me a pic of the correct setup ? I've never seen one.

Thomas Kleman
SM2K 422 L'ORIENT
Panama

Craig & Katherine Briggs SN 68 Sangaris Tropic Isle Harbor, FL
 

Tom has identified his problem - no expansion tank, but I think this topic started with Mawgan's problem of no hot water flowing after he installed a new tank.
Mawgan, how did that work out?

Davi Rozgonyi
 

I have a tangential hot water question on our SM.... it sputters... good pressure but there what is best described as a mix of air that causes the flow to sputter when any 'hot' component is added to the water. Cold water / and freshwater pump run fine with no sputtering.... any ideas? 

 

David,

The simple answer is air is getting into the hot system at a point where the air entry is not "wet."

I'll take a wild guess: 

Here are 3 things to look at, in order of probability:
There is some trapped air in the hot water tank and eventually will stop
The electric thermostat is not turning OFF the heating element, allowing boiling inside the tank.
If the pressure relief valve is located above the tank waterline, it may be leaking, allowing air to pass into the tank.


Best,

CW Bill Rouse
Yacht School - Supporting Amel Owners
www.YachtSchool.us
720 Winnie St
Galveston Island, TX 77550
+1(832) 380-4970


On Sun, Jul 21, 2019, 12:44 AM Davi Rozgonyi <davi.rozgonyi@...> wrote:
I have a tangential hot water question on our SM.... it sputters... good pressure but there what is best described as a mix of air that causes the flow to sputter when any 'hot' component is added to the water. Cold water / and freshwater pump run fine with no sputtering.... any ideas?