Hive Dual Channel wiring

[arisermpo]

Hello!

A friend of mine just brought me a Hive Active Thermostat (Dual Channel) and I'm trying to figure out how to wire it. I have an Y system. There is one 3 port valve, that just cut hot water from getting to radiators when I press the "Boiler" button on my old thermostat.

The current wiring on the old thermostat is like this:

So, as can you see, I don't have a HW OFF or CH OFF wires. They are both bridged to L. Will my existing wiring work with Hive? If so can anyone point out how to wire the Hive receiver? Thank you!

 

[ianmcd]

you dont have a y plan system

 

[arisermpo]

Oh. Looking at various diagrams I thought it was a y plan. Any idea how "my system" is called?

 

[ianmcd]

post a pic of your motorised valve

 

[ericmark]

I think you have a C plan. Hive does have that option it seems.

 

[arisermpo]

Thank you for your answers.

 

[arisermpo]

So I figured out that my plan isn't a Y plan after all, as ianmcd and ericmark suggested.
It's a short of C plan, but the TWO-PORT valve (not 3 port as stated before) controls the water going in home to the radiators.

How I currently operate my old fashioned thermostat: When I want the central heating to go on, I press one button, the boiler comes on and I have bot CH and HW. When I just want HW (e.g. in summer), I press the other button, boiler comes on, the two-port valve closes and the boiler just heats up the water tank. When the water reach a certain temperature point (72C) the boiler shuts itself off.

Is it possible for hive to work with that?

 

[ericmark]

Hive is one of the few modern thermostats with the option for old C Plan, you need to set it and what it does is when either DHW or CH is required the boiler contacts close, and if central heating required also pump contacts, from your description the motorised valve will connect with the pump, this is in fact unusual (although how mine also works) in the main the motorised valve is for the DHW, by adding a tank thermostat and motorised valve to the old C plan it stops DHW getting too hot, by just adding a tank thermostat you can leave running in summer. So there are three versions of C Plan, I know Hive will work with basic version, not sure about the others.

Original C Plan with tank thermostat and with tank thermostat and motorised valve they all use thermo-syphon or some times called gravity for DHW but the control has changed. I have the original but with two pumps and motorised valves so it can either heat main house or flat or both, so can't really be sure when it has a motorised valve why the valve is fitted, in my case the valve stops the water reverse flow, without valves my house will get warm when flat only selected and visa versa. I am warned not to fit a motorised valve to boiler as it has no run on and needs to be able to cool by heating domestic hot water, I use Nest gen 3 and that allows you to configure the volt free relays, Hive is different it is done in the software you select gravity.

 

[arisermpo]

Thanks again for your time.
Now I'm confused about the gravity part, since in my system there is a pump prior to the Two-Port Valve. This pump serves both DHW and CH, as shown below:

CENTRAL

• arisermpo
• 22 Dec 2020

SXEDIO

• arisermpo
• 22 Dec 2020

Should I configure hive to "Gravity"?

Also, should I try connecting L (from old thermostat) to L (hive receiver), N to N, HW On to HW On and CH On to CH On? I guess when the thermostat reaches desired temp it will shut off and when I don't want any more DHW i should turn it off my self (as it happens now).

 

[ianmcd]

Also, should I try connecting L (from old thermostat) to L (hive receiver), N to N, HW On to HW On and CH On to CH On?

yes and set the hive to Gravity hw , even though it is pumped, it is just how it works.

I guess when the thermostat reaches desired temp it will shut off and when I don't want any more DHW i should turn it off my self (as it happens now).

No it wont stop heating when the HW gets to temp , your boiler thermostat will control the temp that the HW cylinder gets to, post a pic of the thermostat you are saying you turn down on the HW

 

[arisermpo]

Maybe I didn't write it as good but I meant exactly what you said. Right now when i need just the DHW, I press the "hot water" button. It will stay on untill I press it again. But the boiler it self stops working when water reached 72c. When I want it to "totally" stop I press the "Hot Water" button again.

When I press the Heating Button I get both HW and CH.

 

[ericmark]

With my Nest I can set the DHW time, in winter set off, as it heats anyway, in summer ½ hour 5 days a week, I find that is enough to keep it warm. On my to do list is to fit a wireless thermostat on my tank, or run wires, but not very high on list, I have considered a timer on the immersion heater, at the moment the immersion is never switches on, my worry is legionnaires, the idea it to get the water hot at least once a week, to kill bugs, so having the immersion switch on for an hour after a boiler burn would means it would go up to temperature one hopes once a week, but very low down on jobs to do list.

 

[arisermpo]

To be honest, the "Just Hot Water" option isn't used that much. I'm from Greece and I have a solar panel fitted for HW, too. From mid-March to late October my HW neees are satisfied by that system. The change between the two systems is controlled by a switch connected to a 3port valve.

 

[ianmcd]

you are confusing people with your terminology, a 3 port or mid position valve is a a Y plan, you have a two port valve on the heating system, and the switch over from your solar to system heating is called a diverter valve, they are not the same thing, yes it has 3 ports but not the same as a Y plan

 

[arisermpo]

Oh I'm really sorry about that. Since in Greek they are both called the same, I thought it was the same in English.