need help with underfloor heating

[BenC]

hi ladies and gents hope you can help me here,
in the process of buying a house and im going to fit underfloor heating ive got a manifold just need a pump and blender pack, but from what i can see it is basicaly a very expensive tmv, so im trying to save money and build it up myself just wondering if it will work and if so is my diagram correct?, is the pump in the right place? or could i get rid of the pump completely as theres a pump in the boiler and seems daft using two pump expecialy as im only having ufh no radiators well apart from a towl rail in the bathroom.

 

[BenC]

the room temps will be controled via room stats and actuators on the manifold

 

[BenC]

unsure, but whats in a normal pump pack to cover if the tmv in that fails

 

[BenC]

wouldn't the room stats cover the tmv if it fails as the room would heat up stat would reach its working temp and then tell the actuator to shut that zone down. so once every stat has told all the actuators to shut down there would be no water circilating the circuit.

 

[BenC]

the necessary controls.

what are the necessary controls? or do you not know?

 

[BenC]

well what if there was a pipe stat wired in just after the tmv to shut the boiler down if the flow from the tmv got to hot

 

[markfxy]

If the boiler is just for ufh you wont need the extra pump or mixing valve just turn the stat down on the boiler use a manofold with thermostatic heads on each circuit

 

[BenC]

ye still not sure about the pump if the system needs the 2 pumps or not, i cant see why it would aslong as the one in the boiler was cabable of moving enough water around the system, the house isnt very big.

 

[Plucky]

Simon give the guy a break, ive seen quite alot of UFH set ups done the was Ben wants to do it.


Ben the pump your pump is in the wrong place.

You need to move the pump to the outlet of the blending vlave so that it can pull water back from the return of the manifold through the blending valve.

It is also important to install an Auto bypass between the flow and return pipes before the reach the manifold so that when the hot inlet on the blending valves winds down the by pass opens and the boiler will shut down on its thermostat.

On a packaged UFH kit there would possibly be some form of temperature protection within the wiring centre/logic box that can be enabled/disabled using dip switches.

 

[BenC]

If the boiler is just for ufh you wont need the extra pump or mixing valve just turn the stat down on the boiler use a manofold with thermostatic heads on each circuit

ye boiler is just for underfloor heating but there will be one towel rail in the bathroom

 

[BenC]

i had realised about the auto bypass just hadnt added it. so like this then

 

[BenC]

what happened to all simons posts?

 

[Gray0689]

This is a set up with a mixing valve

 

[BenC]

cant really make out the pics mate they come out tiny, and what do you mean by moving valve?

 

[Gray0689]

Mixing valve lol spelt wrong

 

[Gray0689]

You can get 28mm mixing valves suitable for underfloor for about £70-£80 watts is the make

 

[BenC]

ye thing ive seen them watts is the make of my manifold funnily enough

 

[Gray0689]

If the boiler is just for ufh you wont need the extra pump or mixing valve just turn the stat down on the boiler use a manofold with thermostatic heads on each circuit

Do t do it this way it's WRONG

 

[BenC]

is the extra pump needed though

 

[Puddle]

Like the idea of a pipe stat to close under floor heating if pipe work gets to hot due to faulty mixing valve

 

[BenC]

Like the idea of a pipe stat to close under floor heating if pipe work gets to hot due to faulty mixing valve

thanks in theory it should work aslong as the sparkys wireing is correct

 

[Gray0689]

thanks in theory it should work aslong as the sparkys wireing is correct

Will end up costing you more
Just get a mixing valve and pump job done
Your way is frankly a bit silly