12v gate valve. 15mm required

[magnetman]

I have calorifier and instantaneous water heater with 2 gate valves used to switch from one to the other. one valve is in the galley so easy to access but the other one is close to the calorifier and more difficult to get to.

 

I would like to motorise the latter valve so I can open or close it from the galley. its on 15mm pex pipe.

 

I was thinking of using a central locking motor to actuate a lever valve but there must be an easier way?

Edited May 12, 2013 by magnetman

[twbm]

Assuming the calorifier stays cold if the engines not running, hence the need for the instant one, is it feasible to run the water through calorifier then the instant heater? Theoretically all you've got to do then is turn the instant heater off or right down when you don't need it?

[Bobbybass]

I did this a few years back..and when I looked at it the cost of a specific 12 volt gate valve and its effectiveness didn't add up. In the end...I got onto Ebay and bought a £15 inverter 12 volts to 240 volts..and used it to drive a 240 volt gate valve. The switch sent 12 volt to the inverter and the 240v operated the valve.

[magnetman]

re twbm's post

 

the risk of boiling is present if you do that.

 

my central heating is coming on 4-7am at the moment so calorifier is hot in the morning then swmbo complains when it starts cooling down so i'm looking for a seamless transition from calorifier to water heater without having to access the calorifier cupboard to turn the valve.

Edited May 12, 2013 by magnetman

[Timleech]

Would a solenoid valve do the job?

ebay 330744783150 for instance?

Max temp 95 deg. in this case.

 

Tim

[magnetman]

I wondered about that but I have an idea they draw power continuously in one or the other position. not sure though.

[Timleech]

I wondered about that but I have an idea they draw power continuously in one or the other position. not sure though.

 

Yes they will, usually in the open position, you would have to decide whether it was enough to rule them out.

 

Tim

 

Edit - just checked that Chinese ebay item, it says 250mA (quarter of an amp).

 

Tim

Edited May 13, 2013 by Timleech

[Bobbybass]

Would a solenoid valve do the job?

ebay 330744783150 for instance?

Max temp 95 deg. in this case.

 

Tim

 

I bought several of these for a boat project...and when connected to 12 volt..they never did anything..not even a buzz ?

No idea why...and couldn't be bothered to send them all the way back to China...

[Ray]

Have you had a look at these?

Low voltage valves? We have two on our boat. One operated by the switch that is the room thermostat and the via the cylinder thermostat on the calorifier (which has a separate switch in series so that the boiler doesn't fire if we're planning to run the engine).

 

They're quite (although you can hear them to confirm that they are operating).

 

We don't live aboard and do tend to cruise everyday so current drain (which isn't that great) isn't normally a problem especially as they're only powered up when they're open.

[twbm]

re twbm's post

 

the risk of boiling is present if you do that.

 

my central heating is coming on 4-7am at the moment so calorifier is hot in the morning then swmbo complains when it starts cooling down so i'm looking for a seamless transition from calorifier to water heater without having to access the calorifier cupboard to turn the valve.

 

OK, Thanks. If we ever upgrade from The Big Blue Kettle we won't do that!

[smileypete]

If you look for '12V motorized valve' on Aliexpress there's quite a few of the ones Ray mentions at much lower prices, albeit with long shipping times, but maybe about £20-30 delivered.

 

I wonder if there's some way of doing the switching with one valve instead of two.

 

cheers, Pete.

~smpt~

[Ray]

From memory they do make a changeover valve, but I'd suggest you check that I'm right. We didn't need one so I didin't take it any further.

[David Mack]

I wondered about that but I have an idea they draw power continuously in one or the other position. not sure though.

 

But these don't. And at less than £20 including delivery, they are rather cheaper than Ray's option

[magnetman]

 

OK, Thanks. If we ever upgrade from The Big Blue Kettle we won't do that!

I only know this because my previous boat had this setup and when I first got it I used the instant water heater not knowing that they raise the temp BY x degrees not TO x degrees.

 

the engine had been running and the calorifier was hot,which meant the heater raised the temperature to a point where it would have been suitable for making tea !!.

 

if someone was in the shower when this happened it would have been bad.

 

 

But these don't. And at less than £20 including delivery, they are rather cheaper than Ray's option

looks good, thanks

[smileypete]

I only know this because my previous boat had this setup and when I first got it I used the instant water heater not knowing that they raise the temp BY x degrees not TO x degrees.

 

the engine had been running and the calorifier was hot,which meant the heater raised the temperature to a point where it would have been suitable for making tea !!.

 

if someone was in the shower when this happened it would have been bad.

If the water heater inlet water temperature was limited to say 25°C using a thermostatic valve (TMV) then it should be OK.

 

That way even if the calorifer is lukewarm it can be used to help assist the shower temp, instead of using water from the water tank which can be near freezing in winter.

 

cheers, Pete.

~smpt~

Edited May 13, 2013 by smileypete

[Timleech]

Interesting that they say that valve is 'DN15'. So far as I can tell, that specifies the pipe size, Diametre Nominal 15mm (same as 1/2" nominal bore) but not the thread, it could be 1/2" BSP or NPT.

 

(ties in with the Tap Connector thread!)

 

Tim

[Chalky]

They're on just about every Jaguar and Land Rover heater system. They're also used by BMW, Ford etc. There are a number of varieties with different switching combinations for use in different applications. Should be able to find something in a scrap yard - they started appearing on vehicles like Range Rover with the previous model (L322) and I know BMW had used them before that.

[magnetman]

thanks, I always like using stuff from scrap vehicles so i'll have a look round

 

this sort of thing?

 

ebay 180948961093

[Chalky]

That's the sort of thing. Usually solenoid controlled so it's worth getting the bit of harness that leads up to it.

[magnetman]

ok ta

[jonathanA]

how about this for the low tech 'no batteries required' option.

 

a bit pricey from screw-u-fix though...

 

http://www.screwfix.com/p/surestop-remote-stop-cock-push-fit-15mm/48604

[Timleech]

how about this for the low tech 'no batteries required' option.

 

a bit pricey from screw-u-fix though...

 

http://www.screwfix.com/p/surestop-remote-stop-cock-push-fit-15mm/48604

 

Neat idea. 60C max temp might be a limitation for the OP, though.

 

Tim

[Tom and Bex]

 

But these don't. And at less than £20 including delivery, they are rather cheaper than Ray's option

I've used 2 of these on our boat to do exactly what the OP is doing and they work really well. Much easier to have a single switch to switch between calorifier and instant water heater than messing about with manual valves in cupboards. Also have one of the larger ones fitted in the central heating circuit to use webasto to heat all radiators and calorifier or just calorifier.

 

In answer to Tim's question the DN15 one is 1/2" parallel thread.

 

Tom

[Timleech]

I've used 2 of these on our boat to do exactly what the OP is doing and they work really well. Much easier to have a single switch to switch between calorifier and instant water heater than messing about with manual valves in cupboards. Also have one of the larger ones fitted in the central heating circuit to use webasto to heat all radiators and calorifier or just calorifier.

 

In answer to Tim's question the DN15 one is 1/2" parallel thread.

 

Tom

 

I guessed that, but is it NPT or BSP?

 

DN15 is a pipe size, not a thread size (so far as I am aware).

OK the two are the same pitch and can probably be screwed together, but not ideal if the threads don't match.

 

Tim

[Tom and Bex]

Sorry, meant to say 1/2" BSP

 

Tom