I have set the levels for the screed, although it is a bit difficult because the membrane on the floor will be held down by the weight of the screed. So it is difficult to set an exact level to work to because the moment you put the screed on it changes!
I have my father in law and a couple of brother in laws coming on Saturday to get it done…..I hope. Having had advice from lots of people I am using a mix of 5 parts sand to 1 part concrete with some plasticizer to make the mix more workable. It seems that you have to add just enough water to make it hold together.
Everyone with any experience has been telling me I shouldn’t do the screeding but the problem is that I can’t get any one to do it so I have to it myself. I had a go at a little corner this week to see how difficult it is. Only just having enough water is obviously the key, I drew a piece of wood over it to level it and then used the float to polish it off. It seemed far easier than everyone told me, but I suspect that by the time I have finished I’ll have changed my tune.
The central heating wiring baffled me. The under floor heating required a separate zone which confused the wiring even more.
Each zone valve (there are three) has five wires. I took me a while to find out what each did, but the manufacturers have quite a exhaustive website which helped.
Green/Yellow = Earth; Blue = Neutral; Grey = Live; Brown = Switched live; Orange = Switched live return.
When you have got your head round it though it is quite simple. There is a number of switches which all have to be on for it to work. The timer goes to the thermostat the thermostat to the zone valve the zone valve to the pump and the boiler.
It all works well apart from the under floor heating.
The under floor heating is further zoned. It is like four zones within one zone, but it has a simple pre-wired connection block in order to make life easy for you. Unfortunately I inverted the wiring on one of the thermostats and that blew all the fuses. I found the problem and replaced the fuses and it still doesn’t work. It was getting late so I thought I would follow the trail with a multi-meter when I am more awake!
I have fitted central heating once before. I piped the system and some one else put the boiler in. This time it is slightly different because all the pipes for the radiators are there but I have had to dismount and remount the boiler.
This system has three zones: 1. Radiators, 2. Mains Pressure Hot Water, 3. Underfloor Heating.
I hate working with copper pipe. It is very frustrating. It takes ages to cut and solder. I prefer plastic and the fittings by John Guest, it is so much easier to use. The only problem is that you are not supposed to use it within 3 feet of the boiler, so you have to use copper for some things.
I have not worked with these funny mains pressure expansion tanks before, so it has been a bit of a puzzle working it out. I think I have just about worked it out now.
Today’s job is to fit the new flue to the boiler and do the all the wiring for it.
