Heating control replacement

[jonboy81]

Hey guys

An issue I know is asked about often and I have read through some other posts here which have helped a lot, but just had a couple of questions if anyone can advise...

I have just bought a house which has an immersion heater hot water system controlled from a gas boiler, controlled by a an old honeywell ST699 controller which I find rather outdated in terms of on/off options. Im going to replace it with a newer 7 day digital controller, something like the honeywell sundial RF packs seem to be what I want (and I can replace the old mercury thermostat in the hall with the new digital one while Im at it).

My two questions are:

The current controller is in a cupboard next to the boiler, boxed in by the previous owner in the downstairs loo. Not the easiest of places to access - I can straight swap the controller in that location I know, but can I replace the controller in this location with some kind of wireless receiver/relay which is wired to the boiler, then have the actual controller as a wireless one mounted somewhere more convenient in the hallway? I can't tell from the various options on the RF packs if this is an option. Something like this seems like it would work?

http://www.jtmplumbing.co.uk/heatin...1004-pp17987?gclid=CI3-4qbBltACFRa3GwodDGMIuQ

Secondly there is a dial thermostat on the hot water tank. Would this cause the boiler to stop heating after the water in the tank reaches temperature, or is the thermostat on the tank only for when the electric immersion part of the tank is turned on? (which is just the electric back up - it is primarily heated by the gas boiler). I feel the tank is massively inefficient and some point id hope to swap the whole system to a combi boiler but thats a job for another time. I notice the RF packs have some options for a wireless cylinder thermostat...I don't really know what that is. Would it help limit the amount the boiler is burning through gas heating the water by shutting down when its at temperature, or does the existing dial thermostat on the tank do that? Or does it just not work like that?

Many thanks in advance for any advice on either point!

Cheers

Jon

 

[pushreset]

Hi Jon, just had a quick look on the Honeywell site and it seems you can upgrade to the Evohome system.
Will need full details of your heating system to be certain if it is compatible
Your cylinder thermostat is probably just a bi-metal on/off switch, where as the Evohome will monitor the temperature for intelligent control.

 

[jonboy81]

Thanks for the reply. Had a quick look at the evohome system...it sounds great, i might be interested but its about twice the price of just replacing the heating controller and thermostat. I wouldnt go for zoning control at this stage - its about 700 quid compared to 150 for simple controller and thermostat option but if I could control the hot water better etc I might be tempted with the basic evohome package for around £350...Im just not sure if its worth the extra money at this stage. Having just bought the house theres lots of things to sort and spend money on, so would need to be convinced this is worth the extra money! Why do you think it would be the best option?

Not sure what info you need but its a Weisman Vitodens 100w WB1B boiler. Its situated downstairs, and upstairs is the hot water tank. All I can see written on that is the immersion heater part "Heatrae Pullin 95110401 3kw length 27" (this is from the label on the black part on top of the tank - I think that is just the actual electric immersion rod??) and the dial thermostat on the side I mentioned is a honeywell L641A1039 which seems to just be a simple basic thermo for the tank - does this mean the boiler shuts off when its at temperature?

Another factor for me would be to be able to do this myself...im not qualified as a plumber, and not an electrician although do have access to one! Just looking for a DIY option, if the evohome option involves more than I can handle myself id prefer to keep it simple for now - especially as I may switch to a combi at some point anyway.

Primary concerns right now - being able to do it myself easily and cheaply, not going crazy on price, more options for the timer/controller and ideally more control over the water tank so its not just on for two hours straight for no reason.

Secondary if I could it would be a better position for the controller, and yeah if I can get lovely wireless hi end control over the hot water, heating etc with evohome and it doesnt cost an arm and a leg and can be done myself i'll certainly consider it provided it can be used at a later date with a new boiler system should I choose to change over....no point spending the etra and not making use of in a year or two.

Cheers!

Jon