Model Boat Mayhem

The Shipyard ( Dry Dock ): Builds & Questions => Steam => Topic started by: DBS88 on February 18, 2023, 06:36:19 pm

Title: Boiler Water Level Control Unit
Post by: DBS88 on February 18, 2023, 06:36:19 pm

Hi its been a while since I have been able to experiment and use my steam plant (life has been busy), so today was the first day back at the work bench and this afternoon I have tested a new electronic water level control unit for use with our model boilers. The unit senses the level of water in a header tank and also in the boiler. When the water level in the boiler drops below the sensor an electric pump starts or if you are using an engine driven pump a servo opens and closes a by pass valve. Once the water level returns to the sensor the pump keeps running for 15 seconds, 30 second, one minute or two minutes depending on how much additional water you wish to go into the boiler before the cycle starts again. The unit is made by Dénes designs

[color=var(--blue-link)]https://youtu.be/Pf-3yVGfrVg (https://youtu.be/Pf-3yVGfrVg)[/color]

Title: Re: Boiler Water Level Control Unit
Post by: CliffW on March 25, 2023, 01:12:35 am

Clever design...looks like it would take a good bit of trial and error to get the run time sorted to match consumption.

Title: Re: Boiler Water Level Control Unit
Post by: DBS88 on March 25, 2023, 08:23:58 am

Hi Cliff, the pump delivers more water than is consumed by the boiler ensuring the water level in the boiler will rise. There is a water level sensor on the sight glass when it detects that the water level has fallen below the sensor the pump is tuned on, when the water rises above the sensor the pump continues to run for a user preset period of 15, 30, 60 or 120 seconds and then the pump turns off. If for some reason the water level didn’t go above the sensor after a short time the system goes into alarm. So there is no need to mess about trying to match the pump to demand, it’s taken care of automatically and works really well.

Title: Re: Boiler Water Level Control Unit
Post by: rhavrane on March 25, 2023, 10:19:22 am

Bonjour,
Based on my different experiences with electric pumps
JMC : https://youtu.be/smkXCsac4tg
Regner : https://youtu.be/FYTYjJXoc1E
Microcosm : https://youtu.be/uW7OW941xG0 and I have several others,

I can tell you that these pumps have a very low throughput capacity especially at 60-70 RPM, this is why I manually manage them a few minutes after the beginning of a navigation with boiler full.

All of them have been tested in my bathtub :-))  and have been a little bit disappointed by the figures, about 40 cl per 15 minutes. Of course, the quicker they operate, the better is the flow, but that means higher voltage and heavier batteries.

Title: Re: Boiler Water Level Control Unit
Post by: DBS88 on March 25, 2023, 01:36:07 pm

Raphael is right about the pump speed of these microsom units, for about £3 I replaced the supplied engine and gearbox that did 60 rpm at 6volts for a new engine and gearbox that does 280 rpm at 6 volts https://youtube.com/shorts/ce9wC4rbnn8?feature=share (https://youtube.com/shorts/ce9wC4rbnn8?feature=share)

Title: Re: Boiler Water Level Control Unit
Post by: CliffW on March 25, 2023, 03:52:26 pm

Thank you for the additional explanation...sounds like you have this device well sorted!

Title: Re: Boiler Water Level Control Unit
Post by: rhavrane on March 25, 2023, 04:44:36 pm

Bonjour David,
Well done  :-))  I will try to copy you  ok2  Where did you find your engine ?

Title: Re: Boiler Water Level Control Unit
Post by: DBS88 on March 25, 2023, 05:12:26 pm

Hi Raphael, I purchased them via eBay although the seller I bought them from is no longer available. I searched for you and here is a link to the same engine and gearbox, you can select 6 or 12volts and select whatever rpm you want the pump to do. In case the link does not work here is what to search for:


1Pcs 25GA370 Geared Motor DC Motor 6V 12V 24V Electric Gear Motor 4mm Shaft



https://www.ebay.co.uk/itm/204181251147?mkcid=16&mkevt=1&mkrid=711-127632-2357-0&ssspo=0as5azlqrci&sssrc=2047675&ssuid=pISQXRDgTXG&var=504764073177&widget_ver=artemis&media=COPY

Title: Re: Boiler Water Level Control Unit
Post by: rhavrane on March 25, 2023, 07:41:20 pm

Bonjour David,

Many thanks for your quick reply and help, I order one right now  :-))

PS : Aleeady ordered, to be received on first week of June...

Title: Re: Boiler Water Level Control Unit
Post by: DBS88 on April 07, 2023, 08:53:27 am

Here is my recent second test of the Dènes Designs boiler water level control unit. The test is with the boiler water level ok and the header tank water level ok then checking what happens when the boiler water level drop and also the header water level drops below the sensors https://youtu.be/41JYk1btA78 (https://youtu.be/41JYk1btA78) This test is with an un modified microcosm pump that does about 60 rpm - for the intended project I will replace the electric motor and gearbox so that the pump does 280 rpm and will pump enough water for my needs.

Title: Re: Boiler Water Level Control Unit
Post by: rhavrane on April 12, 2023, 06:15:08 pm

Bonjour,

David  :-))   ==> https://youtu.be/FNy_x-RR9mE (https://youtu.be/FNy_x-RR9mE)

Title: Re: Boiler Water Level Control Unit
Post by: rhavrane on April 13, 2023, 06:03:14 pm

Bonjour,

And the real time test : https://youtu.be/j0yn0yaT5F0 (https://youtu.be/j0yn0yaT5F0) :-))

Title: Re: Boiler Water Level Control Unit
Post by: DBS88 on April 13, 2023, 06:23:40 pm

Raphael I am pleased that replacing the motor has worked for you, thank you for sharing your video, now all you need is a way to turn the pump on and off when needed - I look forward to seeing the finished project, well done