Today continued working on what I was doing yesterday. I thought I had it all done then worked out it was all going wrong as it used a load of spline code that I hand’t converted at all.
Went running, it’s now all beginning to defrost, hopefully that’s the last of the snow.
So in the afternoon, in between spline code, or should it be spline code in between everything else….I knocked all the valves off the radiators, opened up all the lock shields, turned the water heating off and then measured everything using the laser gun. I have a feeling the dual probe may not be as accurate as I thought, plus the laser is giving me very consistent results. So I measured everything cold, then let it heat up for half hour then measured it again. This time I was more interested in the flow temperature at each rad. So I made up a table with each rad and wrote down the flow (and return for reference). Initially I had 77 in the bath room down to 72 in the lounge, so only 5 degrees drop. The flow return was more interesting, only 4 degrees across the smallest rads but the dining room and the lounge were showing 21 degrees. So working on the new theory for each degree of difference I tightened up the lock shield by 1/4 turn. I then left it for twenty minutes then measured it all again. So on the second attempt there was still 4 degrees difference, but at least it had dropped by 1. Also the flow / return max drop had gone to 20 degrees. So now round two. Got down to 2 degrees difference and 17 degrees max flow return drop. Round three was 3 degrees and 15 degrees drop. Round 4 was back to 2 degrees and 14 degree drop. I think that’s as best as I’m going to get it, I did one more tweak on the last measure, so will do a final one now. And then when you just start to measure it all the dinning room hit the thermostat temperature and shut the boiler off, so will have to leave it for a couple more minutes. Right, so the final tally is, from worst to last, bathroom an cloak room at 7 degrees difference, not really surprising considering they are by far the smallest rads, you try and get 12 degree drop across something the size of a dinner plate. Second place is the office and hall, next biggest rads at 9 degrees. Jamie’s room and the spare room are at 10 degrees, the kitchen is at 11. The bedroom, on-suite and living room are spot on at 12 degrees and the dining room has 15 degrees. The only way I’d get that slightly better is to increase the pump speed and I don’t really want to go there again. So, there we are, all finally done (hopefully).
Now time for a shower as I’m covered in sweat as it’s about 34 degrees in here at the moment. Then I’ll screw the covers back on the lock shields. It’ll be interesting to see how much noise it generates now as there is an unrestricted flow on both the dining room (which has no TRV) and the lounge, so the pump shouldn’t be able to suck in any air through the vent. We will see.