Installing an extra cast iron radiator on a system run by Autoterm flow 5 diesel boiler

[Tony Brooks]

44 minutes ago, Roberto Conigliaro said:

Thank you! did try my best

 

Hi Tony, now that I know what's the small tank for, I wonder if it can be the cause of a problem i had in the past recent days:

 

The water pump is not in synch with the taps : it actives a few second later I open any tap and it switches off a few seconds after i close the tap - this happened after the water tank got empty (didn't find a water point around Cheshunt..), it is a problem that occurred in the past already but usually it solves itself after a few hours, this time seems to persist. I guess there's some air in the system, I was wondering if you would have any idea of how this can be fixed?

 

The little white "tank" is the cause of what is happening, but it is not a problem, it is exactly what should be happening. From your description, we can see that it is an accumulator.

 

There is perhaps 1 bar (15psi) difference between the cut in and cut out pressure. You close a running tap that creates a lower pressure than the cut in pressure, so the pump runs, filling the accumulator and compressing the air/gas that is inside it until the whole system reaches the cut-out pressure.

 

When you turn the tap on, initially the air in the accumulator forces water from the accumulator and hold the presser above the pump cut in pressure, once the pressure has dropped enough the pump cuts in.

 

If the flow from the tap is greater than the pump delivery volume, then the pump will run continuously until you close the tap and the pressure builds up. If the tap flow is less than the delivery volume, the pump will keep turning itself on and off (cycling) until the tap is closed.

 

All absolutely what is to be expected.

[Roberto Conigliaro]

On 14/11/2023 at 18:42, Tony Brooks said:

 

The little white "tank" is the cause of what is happening, but it is not a problem, it is exactly what should be happening. From your description, we can see that it is an accumulator.

 

There is perhaps 1 bar (15psi) difference between the cut in and cut out pressure. You close a running tap that creates a lower pressure than the cut in pressure, so the pump runs, filling the accumulator and compressing the air/gas that is inside it until the whole system reaches the cut-out pressure.

 

When you turn the tap on, initially the air in the accumulator forces water from the accumulator and hold the presser above the pump cut in pressure, once the pressure has dropped enough the pump cuts in.

 

If the flow from the tap is greater than the pump delivery volume, then the pump will run continuously until you close the tap and the pressure builds up. If the tap flow is less than the delivery volume, the pump will keep turning itself on and off (cycling) until the tap is closed.

 

All absolutely what is to be expected.

 

HI Tony, thanks so much for your reply and sorry for the very late response, after a few weeks, we have still have the exact problem, I see from your explanation how the system works but I am still unsure on how to solve the problem?

 

Also thanks everyone who helped and gave useful tips for the radiator installation, it all works like a treat! 

[Tony Brooks]

1 minute ago, Roberto Conigliaro said:

 

HI Tony, thanks so much for your reply and sorry for the very late response, after a few weeks, we have still have the exact problem, I see from your explanation how the system works but I am still unsure on how to solve the problem?

snip

 

From what I can see, the only "problem" is that you have decided that you have a problem. both Tracy and I have told you that it seem to be operating normally. Even if you have a bit of air trapped in the system, all that will happen is that the run-not run time when the tap is used will be a bit longer than without air in the system.

 

Unless you can show us what is happening apart from the perfectly normal pump cycling, I think the only way to "solve the problem" did for you to accept that it is not a problem at all.

[Roberto Conigliaro]

On 14/11/2023 at 18:42, Tony Brooks said:

 

 

 

On 14/11/2023 at 18:42, Tony Brooks said:

The little white "tank" is the cause of what is happening, but it is not a problem, it is exactly what should be happening. From your description, we can see that it is an accumulator.

 

There is perhaps 1 bar (15psi) difference between the cut in and cut out pressure. You close a running tap that creates a lower pressure than the cut in pressure, so the pump runs, filling the accumulator and compressing the air/gas that is inside it until the whole system reaches the cut-out pressure.

 

When you turn the tap on, initially the air in the accumulator forces water from the accumulator and hold the presser above the pump cut in pressure, once the pressure has dropped enough the pump cuts in.

 

If the flow from the tap is greater than the pump delivery volume, then the pump will run continuously until you close the tap and the pressure builds up. If the tap flow is less than the delivery volume, the pump will keep turning itself on and off (cycling) until the tap is closed.

 

All absolutely what is to be expected.

 

HI Tony, thanks so much for your reply and sorry for the very late response, after a few weeks, we have still have the exact problem, I see from your explanation how the system works but I am still unsure on how to solve the problem?

 

Also thanks everyone who helped and gave useful tips for the radiator installation, it all works like a treat! 

[Tracy D'arth]

Just now, Roberto Conigliaro said:

 

 

 

 

HI Tony, thanks so much for your reply and sorry for the very late response, after a few weeks, we have still have the exact problem, I see from your explanation how the system works but I am still unsure on how to solve the problem?

 

Also thanks everyone who helped and gave useful tips for the radiator installation, it all works like a treat! 

What problem exactly do you think you have please?

[Tony Brooks]

Just now, Roberto Conigliaro said:

 

 

 

 

HI Tony, thanks so much for your reply and sorry for the very late response, after a few weeks, we have still have the exact problem, I see from your explanation how the system works but I am still unsure on how to solve the problem?

 

Also thanks everyone who helped and gave useful tips for the radiator installation, it all works like a treat! 

 

I am confused, I answered this 2 hours ago. basically, unless you can give additional info, the problem is in your mind, not an actual physical problem.

On 14/11/2023 at 17:50, Roberto Conigliaro said:

The water pump is not in synch with the taps : it actives a few second later I open any tap and it switches off a few seconds after i close the tap - this happened after the water tank got empty (didn't find a water point around Cheshunt..), it is a problem that occurred in the past already but usually it solves itself after a few hours, this time seems to persist. I guess there's some air in the system, I was wondering if you would have any idea of how this can be fixed?

 

I think this is the so called "problem".

 

6 minutes ago, Tracy D'arth said:

What problem exactly do you think you have please?

 

We have both told him it is normal but instead of giving us additional info that might show there is a problem he seems to be asking the same question again. it does not help that he has mixed it up in his radiator topic.

[Roberto Conigliaro]

2 hours ago, Tony Brooks said:

 

From what I can see, the only "problem" is that you have decided that you have a problem. both Tracy and I have told you that it seem to be operating normally. Even if you have a bit of air trapped in the system, all that will happen is that the run-not run time when the tap is used will be a bit longer than without air in the system.

 

Unless you can show us what is happening apart from the perfectly normal pump cycling, I think the only way to "solve the problem" did for you to accept that it is not a problem at all.

 

1 minute ago, Tracy D'arth said:

What problem exactly do you think you have please?

 

Hi Tony and Tracey, sorry last message was submitted (empty) by mistake

 

Thanks for your attention to this topic - I think that through the years I managed to get a decent concept of what a problem is : the tap / pump system is not functioning as it should - as I mentioned in the previous messages (maybe not so clearly), the tap and the pump are not synch, the pump starts working only a few seconds after I open the tap, and I stops a few seconds after I close the tap, this create a pressure problem, there's not enough pressure once the tap is open, it takes 2 or 3 seconds to get to the right pressure (pump on), which is a problem especially when using water for very short time (which I do most of the time). This didn't use to happen on a permanent basis and it is causing me a problem, maybe a small one, I guess I can live with it, but still a problem, which if solved would make life easier on the boat and make me not waste water.

 

Thank you

[Tony Brooks]

9 minutes ago, Roberto Conigliaro said:

 

 

Hi Tony and Tracey, sorry last message was submitted (empty) by mistake

 

Thanks for your attention to this topic - I think that through the years I managed to get a decent concept of what a problem is : the tap / pump system is not functioning as it should - as I mentioned in the previous messages (maybe not so clearly), the tap and the pump are not synch, the pump starts working only a few seconds after I open the tap, and I stops a few seconds after I close the tap, this create a pressure problem, there's not enough pressure once the tap is open, it takes 2 or 3 seconds to get to the right pressure (pump on), which is a problem especially when using water for very short time (which I do most of the time). This didn't use to happen on a permanent basis and it is causing me a problem, maybe a small one, I guess I can live with it, but still a problem, which if solved would make life easier on the boat and make me not waste water.

 

Thank you

 

As far as I can see, that is new information. You were talking about the pump and tap synchronising. There are two potential causes:

 

1. The accumulator or expansion vessel if there is no NRV in the system has either failed or needs repressurising. (Accumulator to the pump cut-in pressure - about half the cut-out pressure. Expansion vessel {only if no NRV} at cut out pressure).

 

2. A lazy or sticky pressure switch in the pump. If this is the case and as the internal pressure switches are not the most long-lasting, I would fit an external pressure switch that usually allows both cut - in and cut-out pressures to be adjusted.

Edited December 12, 2023 by Tony Brooks

[Roberto Conigliaro]

3 minutes ago, Tony Brooks said:

 

As far as I can see, that is new information. You were talking about the pump and tap synchronising. There are two potential causes:

 

1. The accumulator or expansion vessel if there is no NRV in the system has either failed or needs repressurising. (Accumulator to the pump cut-in pressure - about half the cut-out pressure. Expansion vessel {only if no NRV} at cut out pressure).

 

2. A lazy or sticky pressure switch in the pump. If this is the case and as the internal pressure switches are not the most long-lasting, I would fit an external pressure switch that usually allows both cut - in and cut-out pressures to be adjusted.

 

Hi Tony, thanks for your reply, in the first message I did say that the water pump and and taps are not in synch and there are delays, but in the last message I guess I explained it more extensively. 

 

Okay thanks, I'll look into the accumulator / expansion vessel pressure level and pressure switch in the pump, cheers!

 

Roberto 

 

[Tony Brooks]

The extra explanation is what we needed. There is always a delay between tap opening and the pump cutting in, and then and being closed, and the pump cutting out, especially with an accumulator. This means the tap and pump are never in synch. The clue was when you said there was not enough pressure when the tap is opened, that means the pressure switch is likely to be faulty. Although, it is always best to check the air pressure in the accumulator or  expansion vessel first.

[Tracy D'arth]

50 minutes ago, Tony Brooks said:

The extra explanation is what we needed. There is always a delay between tap opening and the pump cutting in, and then and being closed, and the pump cutting out, especially with an accumulator. This means the tap and pump are never in synch. The clue was when you said there was not enough pressure when the tap is opened, that means the pressure switch is likely to be faulty. Although, it is always best to check the air pressure in the accumulator or  expansion vessel first.

Do you have a filter before the tap? If so I think it is blocked. Have you checked for a filter between the tank and the pump?

 

Is this on all the taps or just one in particular?

Edited December 12, 2023 by Tracy D'arth

[Roberto Conigliaro]

22 hours ago, Tracy D'arth said:

Do you have a filter before the tap? If so I think it is blocked. Have you checked for a filter between the tank and the pump?

 

Is this on all the taps or just one in particular?

 

Hi Tracy, thanks for your reply, yes indeed there is a filter before the kitchen tap, and the 'problem' seems to be worse in this one in particular, I'll have a look into it, cheers! 

[Tony Brooks]

 

Another new bit of info, although it must be difficult for the inexperienced to know exactly what we need to know to get a decent diagnosis. If any of the other taps also suffer the greater than it once was loss of pressure and flow before the pump kicks in then this filter is less like to be the cause. They always seem to cause a pressure drop so t will take longer for the pump to kick in.

[Tracy D'arth]

Is the tap on the outlet of the tank before the pump fully open? Something is restricting the flow.