Cylander Thermostat

[cjwps]

Hello. This is my first post/question on this forum. A year ago we completed a grannie flat for my m-i-l. My central heating is run mainly by an 18kw wood burning stove factory fitted with a boiler. It feeds into a 500l buffer tank and has an LTC ESBE heat charger fitted. Fire and buffer tank are about 1.5m apart. The electrician insisted that the system should be wired up in such a way that the central heating does not get heat until the hot water is up to temperature. On my old system I had a timer for CH and a timer for water. It was brilliantly simple and worked faultlessly for over 30 years. I was very unhappy by being persuaded to put this new arrangement in and quite honestly it is ****** rubbish. The cylander stat is so inaccurate that you can have 55 degree hot water and a cold house. I have to continually go and turn the stat down until I hear a clunk and then we start to warm up the house. My question is is there an accurate stat that does what it is supposed to do? If not would it be difficult to go back to my original system by rewiring the new controller. The controller is a Horstmann Channel Plus H37XL. The whole system is backed up by an oil boiler which comes on only when I tell it to. The builder, plumber and electrician all thought I was off my rocker not to have the Grant oil boiler on an automatic system. Thankfully I was right and my oil consumption has gone down from 2000l per year to about 300l per year. It will not take long to pay for the new system. Any advise would much appreciated. I am quite happy to photogtaph the system if it would help. Sorry one thing I forgot to mention is that my systme is pressurised. To start with the pressure kept dropping over a couple of weeks. It now seems to have settled down and I can't remember the last time I topped it up.