heating control pumps

[vbyrne]

I have been trying all last week to try to get two pumps to work together as well as work indepently of each othe Ill explain. I have a three channel time clock HW,CH1 and CH2 I have a oil fired burner and two pumps.When I call for CH1 or CH2 I want the two pumps to run when I call for hot water only I want one of the pumps to run and I have a fire with a back boiler that heats the water and that will bring in the other pump to run some one has told me that I have to use a relay I know very little about using relays could some one please help me out

 

[adamh]

just been trying to think but it is late and there would be a way of doing it with the s/l from the valves without the need for a relay i think but i dont understand why you would need to? Could teh plumber not incorporate a seperate pump that could be fired up for the hot water?

 

[vbyrne]

I forgot to say there is no motorised valve on the hot water which is causing back feeds from the back burner stat

 

[sparkygary88]

just out of my time and the only thing i dont understand is heating,basic heating in general,has any1 a good way of explaining it simply?sorry to get off subject.

 

[sparks1234]

Heating piece of cake, 2 systems generally used, a Y plan which is one valve that controls the hot water and heating or, S plan which is 2 or more valves which controls different zones, the S plan is IMO a better way of controling things and easier to expand on.

 

[vardymr2]

Only do you need both pumps to run when the CH is turned on? As stated by sparks the plumber needs to plumb the heating to either a S, Y plan. I have tried to wire something like this before it just turned out to be a big headache and the plumber was called back to put in the job right

 

[andyb]

2 pumps require you to install a relay otherwise there is a common path via the boiler to both pumps, which means that any time that one pump is called upon to operate a signal will go from the boiler to the other pump.

Hope this helps.

 

[Guest123]

I think the situation would be made far easier by having a motorised valve installed onto the hot water feed.

A 3 pole relay is required to accept the 3 incoming call signals with a common output signal to each pump.


Having pondered on it some more it would appear that as you will have 2 input signals to one of the pumps, a further 2 pole realy may be required

 

[sparks1234]

Think you gonna need 4 relays, I have drawn it out and will go through it later and if it is ok will scan and post it

 

[Sparky-Tom]

Sorry about the size, I didnt realise it would be this big! I also assumed the voltage was 240VAC and that they would be single phase motors?

 

[sparks1234]

trouble is you have linked the2 heating zones and not included the back boiler

 

[Sparky-Tom]

Could the signal from the back boiler not be put onto the coil of the relevant relay? Or am I missing the point?

 

[sparks1234]

you need chan 1 and 2 to be seperated via relays or else the 2 zones will come on together

Think we need some better idea of what is actually required, is the back boiler the only boiler in the system?

This would be so simple if there were zone valves (2 port) installed

 

[andyb]

Do you want both pumps to run when ch1 or ch2 is calling or pump 1 when ch1 is calling and pump2 when ch2 is calling?

 

[vbyrne]

Thanks lads for all of that,Lenny is right there will be two signals going to the heating pump one from either of the heating CH,which will come on with the other pump as well and another signel that will bring on the pump on its ownwhen hot water is called for on its own the only time the other pump will be on is when the stat on the back burner calls for it to pump water away from the cycindier so kep on going lads we are making good progress

 

[andyb]

I've made a drawing in word of what I think you need but I don't know how to up load it to the forum.

Can anyone advise me on this.

Basically you need a 3 pole relay, ch1 feeds the common of the 1st pole, n/o & n/c both go to pump 1.
ch2 feeds the common of the 2nd pole & the n/c feeds pump 2 & the boiler, n/o is not used. These 2 commons are linked.
A permenant live feeds the common of the 3rd pole and the n/o feeds the boiler & pump2, n/c is not used.
The coil is fed from the hot water demand.
This way if hot water only is called for pump2 & the boiler will be on but not pump1.

I hope this is clear but I can post a basic drawing if someone tells me how.

 

[sparks1234]

Right lets get to the bottom of the requirements.

Channel 1 requires pump 1 and pump 2 and the back boiler to come on
Channel 2 requires pump 1 and pump 2 to and the back boiler to come on
Hot water requires pump 1 and the back boiler to come on

Is this correct and is there anything else involved

 

[Spudnik]

I've made a drawing in word of what I think you need but I don't know how to up load it to the forum.

Can anyone advise me on this.

Can you not save it as a jpeg and upload to somewhere like photobucket?

 

[andyb]

Can you not save it as a jpeg and upload to somewhere like photobucket?

I've tried to save it in different formats but I only seem to get the option to save it as a word file.


If someone tells me what to do I'll have a go.

 

[vbyrne]

andyb I think you have it nearly cracked but you are talking to someone who has never rally worked with relays before,from what you are saying I can get a relay from the wholesalers with three different sets of terminals each one will have its own set of common terminals so in fact a relay is just a two way switch that is switched with the coil am I right in saying that

I've made a drawing in word of what I think you need but I don't know how to up load it to the forum.

Can anyone advise me on this.

Basically you need a 3 pole relay, ch1 feeds the common of the 1st pole, n/o & n/c both go to pump 1.
ch2 feeds the common of the 2nd pole & the n/c feeds pump 2 & the boiler, n/o is not used. These 2 commons are linked.
A permenant live feeds the common of the 3rd pole and the n/o feeds the boiler & pump2, n/c is not used.
The coil is fed from the hot water demand.
This way if hot water only is called for pump2 & the boiler will be on but not pump1.

I hope this is clear but I can post a basic drawing if someone tells me how.