Under floor heating problem

[kurtuk]

the sensor you are describing is connected to the thermostat head and therefore has been disconnected.
are you saying the 30 degrees is the correct temperature for ufh to be working at? if so, why arent the rooms heating up?
as the sensor has been removed as well as the thermostat head shouldnt the water in the manifolds be very hot by now?

 

[Norcon]

The heat pump guys like to run them at around 30c but the loop spacings are from 100- 150mm.
Surfaces need to be tiles ideally.

How many loops are on you're manifold and what size area is it?

 

[kurtuk]

ok, so if the sensor is removed then the temperature should be much higher should it not? also if 30 degrees is the correct temperature then how is it meant to heat up the rooms? i was told that the correct temperature is around 55 degrees.

 

[picasso]

no I am not saying that 30c is correct , what I am trying to explain is that these valves dont close, they are set to give a temprerature of between 22c to 65c approx, if the sensor valve is knackered it will go to whatever minimum temp is set, in your case 30c,

the fact that your system is running at 30c points to it being the valve or sensor.

 

[kurtuk]

sorry for the misunderstanding.
if the valve is not working correctly then is it normal that when the manifold pump is switched off, the hot water passes through no problem and the manifold gets hot to around 60-70 degrees?

 

[picasso]

yes thats right, the flow from the boiler short circuits across the manifold to the return because there is no pressure from manifold pump to divert the water around the floor circuits.

if there are no actuators on your manifold, there should be a 2 port valve controlling the flow from the boiler.

 

[kurtuk]

i understand this but if the valve is not working (stopping hot water getting through) when the manifold pump is on, how does the hot water get through when the manifold pump is off?

 

[picasso]

because the valve is a mixing valve not an on/off valve, when the manifold pump stops , the pressure from the system pump pushes water across the manifold, there should be a 2 port valve to stop this.

 

[kurtuk]

ok, this makes sense.
how do i confirm whether the valve is working or not before having it changed if necessary?

 

[Norcon]

The valve body will probably have a small pin sticking out. Try pushing this in and see does it move back out. It should move freely.

 

[kurtuk]

yes, the pin moves in and out freely.

 

[Onetap]

how do i confirm whether the valve is working or not before having it changed if necessary?

You find a competent technician to diagnose the fault and carry out the necessary remedial work. If you don't want to pay the amount a competent technician would charge you, then you could undertake the study necessary to become competent in this area; it would probably take you a few years.

Some of the seemingly helpful suggestions offered above are a bit confused.

If it was working previously and no other amendments were made to the system, then it is very probably the thermostatic valve actuator. The capilliary tubes are fragile. Pushig the pin in and out should operate the valve and alter the flow temperature; I'd suggest you find a screw cap that fits the valve, the same as the ones supplied with thermostatic radiator valves. IF you can control the temperature manually, the control head is defective.

If it wasn't working previously, if other alterations to the system have been made, or it has never worked, then there are too many possibilities to daignose the fault over the internet.

 

[picasso]

its more a process of elimination than trying to confirm the sensor is creamed, I cant see what else would make your manifold do this than a duff sensor or valve head.

 

[picasso]

Some of the seemingly helpful suggestions offered above are a bit confuse.

which bits do you reckon are a bit confused?

 

[kurtuk]

You find a competent technician to diagnose the fault and carry out the necessary remedial work.

i would love to find such a technician.

however, i would prefer to "know" what the problem is so that i am not taken for a ride.