boiler water pressure for a 3 storey house

pieroabcd

Hi,
after finally replacing the dreadful old flat radiator in the boxroom and rebalancing the system I've managed to get  the radiator at the second getting properly hot.
Basically I had to almost choke all the radiators in the house at the ground floor (both inflow and outflow), choke just a tiny bit less at the 1st floor, and in spite of this they are hot to the touch.
The previous owners had opened ALL valves at the maximum in all floors, no surprise that nothing was getting to the second floor.

It's very surprising how little these valves must be open to get hot enough! It's literally just a tiny bit.
We'll see this winter.

FreeBear

pieroabcd said: The previous owners had opened ALL valves at the maximum in all floors, no surprise that nothing was getting to the second floor.

If he/she had messed with the lockshields, i wonder if the pump & boiler settings have also been messed up. The circulation pump should be set at the lowest speed to get water round the system. Modern pumps often have additional settings that automatically adjust the speed depending on flow & pressure. Might be worth finding a copy of the installation manual for the boiler and have a good read. If you are unsure about what settings to adjust/reset, get the engineer to have a look when boiler has a service.

Windofchange

I had this in our house which is a similar size to yours when I replaced three of the normal style rads with big column type ones. I’m assuming the extra water now in the circuit within the column rads in essence meant nothing hot was getting upstairs. Took a couple of hours one Sunday of rebalancing system and all was fine. You are right, it’s weird how little of a turn on the valves some need to get them piping hot - our closet ones to the boiler are perhaps open a quarter turn from closed. Others up the top in the loft conversion are near fully open. Live and learn. 

jimbog

Windofchange said:

I had this in our house which is a similar size to yours when I replaced three of the normal style rads with big column type ones. I’m assuming the extra water now in the circuit within the column rads in essence meant nothing hot was getting upstairs. Took a couple of hours one Sunday of rebalancing system and all was fine. You are right, it’s weird how little of a turn on the valves some need to get them piping hot - our closet ones to the boiler are perhaps open a quarter turn from closed. Others up the top in the loft conversion are near fully open. Live and learn. 

had new column radiators installed recently and watched as the plumber overcame the problem of 'lazy water' 

ThisIsWeird

pieroabcd said:

Hi,
after finally replacing the dreadful old flat radiator in the boxroom and rebalancing the system I've managed to get  the radiator at the second getting properly hot.
Basically I had to almost choke all the radiators in the house at the ground floor (both inflow and outflow), choke just a tiny bit less at the 1st floor, and in spite of this they are hot to the touch.
The previous owners had opened ALL valves at the maximum in all floors, no surprise that nothing was getting to the second floor.

It's very surprising how little these valves must be open to get hot enough! It's literally just a tiny bit.
We'll see this winter.

Well done!

I did warn you that the lockshield valves closest to the boiler would barely need to be cracked open, but hey :-)

When you 'choke' - nice term - the valves in order to balance a system, the TRV or 'control' valves should be fully open on all, and only the lockshields should be 'choked'. The lockshields set the system 'balance' - ie ensure they receive their correct share of the flow. The other valve controls each rad's output as required.

So, redo everything, but properly this time.

Only kidding - it's a rough science, and most rads are partly or fully on or off in any case. See how it goes, and retweak only if necessary.

With winter coming and associated higher gas bills, it's worth planning out which rads to have on, and when. In essence, turn off any rad in any room that doesn't need heating at that time. If you are concerned about damp, then crack open the windows in these rooms, and shut that door.

pieroabcd

It's what I did: I started the TRV/control valves fully open, but the last radiator didn't receive enough hot water.
After 40 minutes of closing more and more the lockshields there was nothing else to try than to close/choke the TRVs, and so I did. It was only a significant closure of all of them at the first 2 floors that I could finally feel the radiators at the second floor as hot as the others.


Anyway, I realised too late that in the radiator that I replaced myself I've inverted the lockshield and the TRV       
Fortunately the manual of that TRV says that when put on the inflow pipe/hot water I just have to insert the knob head in a different position on the sensor. Fortunately it worked. There was absolutely no way that I would replace once again the valve and the dreadful olive. 
The TRV is Danfoss Radiator Thermostat RAS-C2 Combi.

Since I still have 4 radiators without TRVs, from a technical point of view, is it better to have the TRV on the inflow valve from the boiler or on the return?
In order to prevent people from meddling with the settings it makes sense to keep it on the return, of course, but other than that?
Are they reliable in sensing the room temperature and in reducing the water stream accordingly without needing me to do it manuallu? I suspect that being so close to the source of heat their reading is biased.

pieroabcd

Another queston, about the typical gas consumption in winter.
In the previous house, where I lived with the landlords, when they left me alone for 6 months i resorted to using the thermostat that had been lying there unused for years, even though it was fully working. They preferred to turn on and off at will, but it didn't work very well and it doesn't make any sense from a thermodynamic point of view.
Anyway, I reduced the water temperature from 70 to 60° and set the thermostat at 19° keeping on for 13 hours a day.
It goes without saying that the house was MUCH more comfortable during all the day rather than freezing cold and hot in intervals. I observed an almost constant consumption of 6 cubic metres per day when it was coldest (that means 6 pounds, that isn't high in my opinion).
Is it a typical consumption for a 3 storey house? Theirs is around 140 sqm, just slightly bigger than mine. Contrary to mine they have more open space, without a wall separating the entrance from lounge, so there's more dispersion.