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Z

zammonewfl

Got a wet based underfloor heating system that has been installed but. The guy who installed it for me is on holiday for 2 weeks and I was wondering if the problem is a simple one to solve?

The problem is as follows:
The thermostats do not seem to be regulating the heat in any of the rooms which I'm confused by. 😕
The thermostats have been porgrammed correctly in each room and they have a max min and max temp setting. However, the room's are hotter than the max temp set and the thermostats do not seem to regulate the heat from the UFH system to reduce the room temp. When I took a look at the manifold, the flow rates are high even when the UFH system has heated the room above the 21 degrees (the max temp i have set.) and the bolier keeps firing up to provide the heat which will be costing me an arm and a leg. I assume that once the target temp is met the flow rates should be at 0 till the room temp decreases and the UFH needs to provide more heat to the pipes to bring the room temp back up (the house is well insulated also) to the target temp set?

You are supposed to be able override the programmable function by using the up and down keys on the digital thermostat (model HA208) to inc or decrease the room temp, but that does not seem to work either. The UFH pipes are laid in screed (on a concrete floor in the kitchen (on sandstone tiles and between timber joists in all the other rooms which use engineered timber flooring). At the moment the only way I can regulate the heat is to turn the whole system off and then turn back on when we need a bit more heat. This defeats the purpose of having a digital thermostat so I can control when the heating comes on and off throught the day. Am I able to trun off a particular zone by adjusting anything on the manifold? I noticed there is a temp controller on the manifold itself which was set at 55 deg, I've reduced it to 45 deg - was i right or wrong to do this?

Any help/advice much appreciated. Thanks
 
45 deg is still too hot imho
underfloor heating is not a rapid response system like a traditional radiator setup.
the water in the pipes heats the floor screed and that takes time to heat up and cool down again.
if the floor is heated to 45 deg it will be uncomfortable to walk on and will take a long time to cool down again. i woud recommend refering to manufacturers instructions on settings.
all the systems i have worked on have the heat set somewhere between 25C and 30 c approx

looking at the schematic for that thermostat online i see that thermostat works by sending a voltage to the valve on demand and cutting the voltage on satisfy
so a simple check with a voltmeter at the valve would tell you whats going on if you are competentant to do that.
turn the thermostat right down the power to the valve should cut and it should close and you will see the flow rate on that circuit drop to 0.
if thats not happening then you know its not wired correctly.

as a temporary solution you could turn the manifold temp down much lower (say to 20c) and let it run constantly until your man gets back if you cant rectify the underlying problem
that way it should stay at a more comfortable temp and not waste your fuel so much
 
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