When I moved into my bungalow 10 years ago the central heating was a nightmare. Hot water cylinder on the ground floor and presumably lack of general use of zone valves back in 1971 when the system was installed meant that 2 pumps had been installed. Firing of the boiler was controlled by a 4 pole contactor which was wired incorrectly so hoy water and heating functions were mixed and confused.
I was unable to persuade any local heating engineer to even come and look at it so I set to myself. I sorted the contactor wiring so that the right pump ran according to whether the call was for heat or hot water but a common return meant there was still some crossover between the systems. I sorted this by moving the cylinder from the bathroom into the roof space closer to the kitchen and fitted zone valves on the two systems. Functionally the system now worked properly. Some radiators already had TRV's fitted and I added them to radiators which did not have them, leaving one in the Hall where the Thermostat was located as manual .
We still had problems getting the system right in terms of room temperatures so I installed a Honeywell Sundial Programmer Thermostat but it didn't really solve the problem.
I'm still very technical so decided to look at Smart TRV's. We probably won't be here for years to come so I looked at a fairly low cost approach , ignoring Hive, Nest and others. I bought unbranded Valve heads which actually work quite well and are extremely quiet in operation. I thought that as it is possible to know when the set temperature has been reached in each room then it seems logical to turn the boiler off when no heat is required by any radiator and turn it on again when any radiator calls for heat - First question - Is this a valid assumption?
My problem is that the valves I have bought seem to have a mind of their own and partially open or close as the room temperature approaches the set temperature either rising or falling rather than opening when the temperature is below the set temperature and closing when the temperature. I'm pretty sure that this is the way a standard TRV would operate and the Smart TRV has no other variable user input other than the Set temperature. It is not able to account for other possible sources of heat in the room and therefore shouldn't make that assumption. Second question - is this a correct summary.
The real issue is `illustrated by an actual happening 2 days ago. The Lounge was set at 22° and the recorded room temperature 22.5° The valve was showing as open at 50%. My external control logic assumes anything less than 51% open is in fact closed and will turn the boiler off if no other valves are open. So the boiler and central heating pump were both off. I decided I wanted a shower. The Shower room was set at 15° and the actual temperature was 19° so the valve opening was 0%. I set the temperature to 22° and the valve opened to 100%, the boiler fired, the pump ran shower warmed up nicely but the Lounge radiator got a new heat hit because it was 50% open. The lounge suddenly became uncomfortably warm as the large radiator dissipated that heat.
Final question for now if you aren't totally bored - Is it reasonable to go back to the valve manufacturer (I'm led to believe that my supplier can do this) and request a modification to the software in the valve and suggest as it stands, it is not fit for purpose?
My boiler by the way is an Oil fired Boulter Classic which I believe to be the original installed in 1971
I was unable to persuade any local heating engineer to even come and look at it so I set to myself. I sorted the contactor wiring so that the right pump ran according to whether the call was for heat or hot water but a common return meant there was still some crossover between the systems. I sorted this by moving the cylinder from the bathroom into the roof space closer to the kitchen and fitted zone valves on the two systems. Functionally the system now worked properly. Some radiators already had TRV's fitted and I added them to radiators which did not have them, leaving one in the Hall where the Thermostat was located as manual .
We still had problems getting the system right in terms of room temperatures so I installed a Honeywell Sundial Programmer Thermostat but it didn't really solve the problem.
I'm still very technical so decided to look at Smart TRV's. We probably won't be here for years to come so I looked at a fairly low cost approach , ignoring Hive, Nest and others. I bought unbranded Valve heads which actually work quite well and are extremely quiet in operation. I thought that as it is possible to know when the set temperature has been reached in each room then it seems logical to turn the boiler off when no heat is required by any radiator and turn it on again when any radiator calls for heat - First question - Is this a valid assumption?
My problem is that the valves I have bought seem to have a mind of their own and partially open or close as the room temperature approaches the set temperature either rising or falling rather than opening when the temperature is below the set temperature and closing when the temperature. I'm pretty sure that this is the way a standard TRV would operate and the Smart TRV has no other variable user input other than the Set temperature. It is not able to account for other possible sources of heat in the room and therefore shouldn't make that assumption. Second question - is this a correct summary.
The real issue is `illustrated by an actual happening 2 days ago. The Lounge was set at 22° and the recorded room temperature 22.5° The valve was showing as open at 50%. My external control logic assumes anything less than 51% open is in fact closed and will turn the boiler off if no other valves are open. So the boiler and central heating pump were both off. I decided I wanted a shower. The Shower room was set at 15° and the actual temperature was 19° so the valve opening was 0%. I set the temperature to 22° and the valve opened to 100%, the boiler fired, the pump ran shower warmed up nicely but the Lounge radiator got a new heat hit because it was 50% open. The lounge suddenly became uncomfortably warm as the large radiator dissipated that heat.
Final question for now if you aren't totally bored - Is it reasonable to go back to the valve manufacturer (I'm led to believe that my supplier can do this) and request a modification to the software in the valve and suggest as it stands, it is not fit for purpose?
My boiler by the way is an Oil fired Boulter Classic which I believe to be the original installed in 1971