Amazon Hive Oil boiler with 2 pump

[ben125]

Hi folks,

I tried finding an existing thread about this same issue but i couldn’t so apologies if it already exists

I have an oil boiler with 2 separate pumps one for heating and one for hot water, no motorised valves and was just wondering how I would wire the Amazon hive for it , I have the dual channel one for separate heating and hot water .

Thanks for any help

 

[muggles]

What make & model boiler? It's not an Amazon Hive, Amazon and Hive are two totally separate companies, so if you're searching for that it may explain why you can't find much info

 

[ben125]

You’re quite right, it’s just a huge thermostat, my bad .

The boiler is a Worcester Bosch 50/70

I’ve added photo of it and the two pumps.

Thanks.

 

[ericmark]

I look at the way wired, and it rings alarm bells.

That is no how to wire a socket. It is common to have a C Plan, but that uses a single pump, and so the question is why has it got a second pump?

My own system (also oil) had two pumps, and one running caused water to flow in the reverse direction through the other pump, clearly the installed had thought selecting which pump would select what was heated, but that was not the case.

So question one, how does it work now? It may need non-return valves, or motorised valves adding, or the use of a relay, motorised valves have micro-switches inside, and are used like a relay, so does what you have work?

 

[ben125]

I’ve only moved into the house so I’m not sure who did it or why it was done that way. There are two switches in the boiler house one for “hot water” and one for “heating” ,

If you have the hot water one turned on and turn the boiler on it just heats the water in the tank and if you turn the heating one on it does the radiators and the water in the tank but it heats up slower.

And if you have both switches turned on then the radiators heat up and so does the water in the tank .

Thanks

 

[ChrisJP]

If you can switch CH and HW on separately, and only one boiler, you must have a least one 3-way motorised valve, or maybe two 2-way valves. Otherwise as soon as either the HW or the CH pump is turned on, HW will be forced around BOTH the HW and CH circuits

 

[ben125]

To switch from central heating to hot water only I have been turning the relevant pump off at a switch in the boiler house , in the attached photo. Where would the motorised valve be. I can’t see anything, I don’t think there is one

Apologies for my ignorance, I’m a joiner and know nothing about plumbing or sparking.

Cheers.

 

[oilhead]

This will basically be a gravity hot water , pumped heating but with a pump to assist the hot water. There will be 2 flow pipes and 2 returns at the boiler. The OP does say that with the heating on, the hot water does heat up, and I would imagine that with only the hot water on, there would be some 'creep' into the radiators.
It's a bit of a mare's nest, but the 2 channel Hive could be used to replace the two existing switches with the only advantage being able to switch remotely. It would not be too big a job to convert to Y or S plan and use just one pump and one pair of pipes, but probably above the competent joiner.

 

[Stuart981]

You find on some old oil systems that the primary circuit often includes a towel rail or radiator typically in a bathroom. Sometimes this circuit is extended to provide radiators in remote parts of the house and a second pump is added. If it was done by someone who knew what they were doing then it probably works just fine but you might have to turn off some of the radiators at their wheel heads in the summer.

 

[ben125]

Okay, I would be happy enough with that being able to use the app to just heat the water / turn the heating on separately even if there is a bit of “creep” into the radiators.

You are quite right, the towel radiator in the bathroom is the only one that heats up when the “hot water” pump is on.

How should the hive be wired for this ?

Maybe I’m best just getting a spark out run wires from those two switches into the hive ?

Appreciate all the help

 

[Exedon]

Most of the old oil systems with 2 pumps use relays so the pumps can run independently and both switch live to boiler.
If indeed you have relays you need to run the 2 switch live's from the hive to switch the relays.

 

[Stuart981]

Some of those old systems had no control over DHW and you could get a situation where, if no hot water had been drawn off for a while, there was a risk of scalding.

 

[ben125]

Most of the old oil systems with 2 pumps use relays so the pumps can run independently and both switch live to boiler.
If indeed you have relays you need to run the 2 switch live's from the hive to switch the relays.

I don’t think there are relays , is it possible to wire this hive in without if so how would that be done ?

Cheers

 

[Stuart981]

I don’t think there are relays , is it possible to wire this hive in without if so how would that be done ?

Cheers

If it ain't broke don't fix it.

 

[oilhead]

To retain the control as yo have it at present you need to replace the switched feed from your wall switches to the corresonding outlets on your Hive and the you will have remote control. I could probably do it if it were my own system, but I don't know enough of yours, and as you admit to no knowledge, you would need to employ a professional.