Replacing 80's heating timer (dial) with wireless

[the_toilet]

Hi forum

I would like a little advice. just bought a house and all it has to control the heating is a dial-based unit in the corner of the kitchen. there is no thermostat (other than the throughput on one the oil-burner itself out in the garage).

So with no thermostat in the house, and just this single control unit, is it just a case of removing this unit, and re-wiring the wireless unit into the same loom? is there anything I am missing here? photo would help I guess... (I have not took it off the wall to check the wiring)

There is a master on/off switch to the left (looks like you would have for a master switch for a build in washing machine or other appliance). Then there is the old dial type controller, where there is a circle of switches, each one representing 30 minute intervals, "out" is on and "in" is off etc...

see some good deals on amazon so thought I might just jump and get one... I have a sparky coming to do some other work anyway (like wiring in a new leccy shower) so might just get him to do it,

i guess i just would like to know if I am buying the right thing... as nearly all reviews and discussions are around replacing the thermostat rather than the whole heater control unit...

thanks all

 

[45yearsagasman]

What you propose sounds ok, but a picture speaks a thousand words.

 

[the_toilet]

here is a picture, it is not ideal as I am not at the house right now but it is a crop of one I took of the kitchen as I was working on it and you can see the controls in the far corner.

this is the back corner of the kitchen. both of the walls you can see are external, and directly behind them is the garden and then the garage where the oil-burner lives.

this house used to be a rental before I bought it, so the label on that switch is a bit of a mystery to me. however, I am pretty sure it is related to the heating as that is why it would be always-on. that said, I am still not sure why, unless it is a backup isolation switch so one can simply turn off all power to the boiler & pump... meaning even if the heating-controller said "turn on", then it would still remain off... maybe I should test it...

 

[stem]

You will be able to swap what you have for a modern unit with the same functions. But when it comes to controls it really depends upon the design of the plumbing. For example, you don't mention if the boiler also heats the hot water. Is it a combi? is it a fully pumped system? does it have pumped central heating and gravity hot water? are there any motorised valves? All of these will have an effect on the automation you can have and how you would achieve it.

 

[the_toilet]

hi there, thank you for the reply.

- the oil burner in the garage provides both the hot water and the heating. the pump will be with the boiler and pumps hot water from the garage to the system that then creates hot water and heats the radiators (the bit in the middle I am afraid I do not understand... I figured the pump sends water through the cylinder which has a coil for hot-water, so having the heating on, basically heats the hot water.... with a few islolatio0n valves in palce to allow me to make it only heat hot water if I choose - like in summer)
- there is a cylinder in the airing-cupboard/hot-press for the hot water
- the heating is non-pressurised as it is fed by a small header tank in the attic (previously had a system in a house with a pressure cylinder and no separate header, so assuming this is non-pressurised and only gravity and the header keep air out)
- there is a second header tank (larger) which supplies the hot and cold water feeds what are not mains fed.

all I really want to achieve, is to replace the old dial-based timer control, with an up to date digital timer. but then also add wireless thermostat as there is currently no thermostat in the house...

 

[jackthom]

When you get back some pictures of the boiler/pump/pipework in the garage, the (manual?) isolation valves and especially important some closeups of the timer plus it's wiring should help bring in loads of advice on what's easily doable.

 

[the_toilet]

thanks for the replies. will indeed do that later today... want to get to know the plumbing in this house so do not need to call someone every time there is something small going on....

 

[the_toilet]

hi all... finally got pictures, and also the wireless heating controller arrived so took pics of it too....

you can see the cable going from the back box on the control unit, to the always-on switch to the left...

 

[stem]

You are intending to replacing a timeswitch (which presently turns the boiler and pump 'on' to provide hot water and heating) with a programmable thermostat which is designed to control only central heating. The wiring will allow you to make the swap, but when the radiators have warmed up the property, the programmable thermostat will turn off the boiler which will also turn off the hot water.

The system looks to need updating to include a motorised valve which will enable the separate control of hot water and central heating.

You say that there is currently no room thermostat in the house. So how do you presently stop the heating coming on in the summer when you only want to use the boiler for hot water?

You also say that the pump supplies the hot water from the boiler to the hot water cylinder. Are you sure about that? Sometimes there are separate pipes from the boiler without a pump for this purpose.

 

[the_toilet]

hey there, thank you for the reply...

with regards to the hot water/heating... this house is similar to my last house, where basically there is only 2 pipes form the boiler (in the garage) to and from...

You are right, this will basically turn off the heating AND hot water.. all or nothing. and I never thought about the fact that should the temperature in the house be greater than the new wireless stat, then water will not come on! I am happy to cope with this but I would prefer to be able to have separate controls...

In the summer, the only way to change it to "hot water only" is to set the isolation valve in the hot-press (cylinder cupboard) which seems to stop hot water flow to the radiator network meaning only hot water is created... but as per previous point, one would have to set the room temperature to high enough to allow hot water to kick in...

 

[the_toilet]

I wonder is there a similar unit to the one I bought, that has additional settings... where I can say "on at this time no matter hat the temp is" or something like that... hmmm thinking...

 

[jackthom]

Can you post pictures of the isolation valve that stops the central heating flow and the layout of the pipes around it?

 

[the_toilet]

hi there... I am pretty sure this is it...

 

[jackthom]

That looks like it would only turn off the flow to the hot water cylinder and leave the radiators unaffected, which is the opposite to what you want in Summer.

Can you easily find out where the 15mm pipes are heading off to?

 

[stem]

What you really need to do is install one of these:

Untitled

• stem
• 1 Apr 2010
• 8

This will route the water from the boiler to either the hot water cylinder and / or the radiators as required. Then you can have a room thermostat and a cylinder thermostat to give independent control of heating and hot water. The whole system will require rewiring though.

The red valve on the return from the cylinder in your photo is there to balance the system so that the hot water cylinder doesn't get the lions share of the flow and the radiators are left short.