Testing underfloor heating

[Dan Robinson]

The middle pipe is the gas.

The 15mm pipe of the right is the safety discharge.

I think Vaillant are competent enough to get the stickers and manuals correct.

The 22mm pipe from the left of the boiler should appear on the LEFT side of the manifold.


37kW

I hope you live in a huge mansion.


Anyway - we have confirmed your plumber's IQ is similar to your boiler's output.

 

[Dan Robinson]

If the return manifold is getting hot first then they have plumbed it the wrong way round.


Like I said - builder's in house plumbers are usually ********s of the highest order.

 

[Stephen7]

Conclusion reached then. It was good to eliminate other possibilities!! A point to Dan I think
Solution easy - swap the connections; an unpaid job for the plumber if you want him back in the house.
Schoolboy error without doubt.

 

[Milleniumaire]

Thanks to everyone who contributed, especially Dan for identifying the issue, even though I didn't check the his suggestion as I assumed a plumber would never make that mistake and was blinkered towards the idea of trapped air.

Thanks to Stephen for persuing this at the end when I thought the cause had been found, if it wasn't for you Stephen, I wouldn't have gone back to check the plumbing, only to find that Dan was right!

I'm still waiting for the plumber to contact me to arrange a time to return and fix the issue and the builder has also asked him to setup the UFH on a separate zone, which may not be possible with my existing kit, but that's a separate question........

 

[St0rmer66]

It's very easy to zone off, especially if he's draining it off to swap the pipes over but given that he got such a simple thing wrong maybe he'll struggle with that too!

 

[Stephen7]

You are welcome the main thing is the problem had been found. As St0rmer says zoning is relatively easy as he has to drain the primaries to correct his pipework.

 

[Milleniumaire]

I agree that fitting the zone valve and the additional thermostat should be relatively easy especially as the system will need to be drained to correct the current problem, however, I'm not sure an additional zone can easily be incorporated into my existing Vaillant LC 65 control centre.

I've started a new thread here which gives a little more detail:

//www.diynot.com/forums/plumbing/separate-zone-for-ufh-on-vaillant-system.409495/#3172107

Plus, we are talking about a plumber who couldn't manage to correctly connect a UFH manifold to an existing CH system, so I want to be able to know what is required so I can be sure he understands what needs to be done for the UFH to work independantly of the CH.

 

[mandm65]

Hi Milleniumaire, just got round to reading this thread what a mess you went through, times like this you feel so fortunate to be part of this forum that you get some great help out here.
My CH work and manifold connection (UFH already installed) will start next week and was wondering how best to ensure that I don't face the same/similar problem. I know its highly unlikely but reading post like this make you wonder about the quality of the so called competent HE's out there. As you know my kit is very similar to yours and would like to ensure that installer does not make same/similar mistake and want to make sure that he installs low loss header n that zones (UFH, CH, HW) are separate with correct valves, pumps etc.
I got nervous when I saw order list and noticed the missing low loss header so can anyone please review my order list to ensure I am getting the right kit and perhaps guide me to where I can order missing low loss header ?
Cheers

My kit list as follows:
Vaillant ecoTEC Plus 630 System Boiler
Vaillant Standard Horizontal Air/flue Duct with Elbow and Terminal
Vaillant auroSTOR 310 Unvented Solar Cylinder Twin Coil
Vaillant VRC470 Digital Weather Compensator
Fernox TF1 Dual Action Magnetic Filter - 22mm
Fernox Protector F1 - 500ml
Honeywell Evohome Base Pack
Emmeti 230 Volt 8 Way Wiring Centre
Emmeti 230 Volt Electrothermic Actuator Heads
Emmeti 3 Port Underfloor Heating Manifold Kit & T3 Control Pack
PERT-AL-PERT Multilayer Underfloor Heating Barrier Pipe 16x2m

 

[Stephen7]

Hi MandM65.
You should not need a low loss header. The boiler has a hot water priority which means the HW is done independently of the CH.
If you have a combination of UFH & Rads then each can be controlled by using a simple 2 port zone valve on each - one or both can then call for heat from the boiler.
You do need to have a time / temperature control for both the rad & UFH circuits.
In simple terms the stat calls, opens the valve, the boiler is asked to produce the CH water. Standard install for a competent HE.
Hope that helps.

 

[Milleniumaire]

Hi mandm65,

I had a Vaillant registered installer around this afternoon to discuss what needs to be done to get my UFH into a separate zone and correct the mess left by the builders plumber. We briefly talked about low loss headers and he agreed it shouldn't be necessary on a single boiler setup. Also, I have a document from Vaillant (AIUFH2) showing how to include UFH in an existing Vaillant setup. While this also shows a low loss header, I queried this with Vaillant technical support and they agreed it isn't really necessary in a small setup like mine.

Regarding your setup, I obviously don't have the knowledge to suggest how it should be done and it appears you are using non-Vaillant wiring centres, but I just wondered if you were using a separate room thermostat for your UFH.

 

[mandm65]

Hi Stephen,
thanks for your help

You should not need a low loss header. The boiler has a hot water priority which means the HW is done independently of the CH.

Fantastic news, i was worried for nothing.

If you have a combination of UFH & Rads then each can be controlled by using a simple 2 port zone valve on each - one or both can then call for heat from the boiler.

Yes I do have a combination of UFH & Rads so missing item from my list is a simple 2 port zone valve, correct?

You do need to have a time / temperature control for both the rad & UFH circuits.

I believe the Honeywell Evohome Base Pack can take care of this?

In simple terms the stat calls, opens the valve, the boiler is asked to produce the CH water. Standard install for a competent HE.
Hope that helps.

I hope too that it would be Standard install for a competent HE. BTW int the post above Milleniumaire mentioned that i am using non-Vaillant wiring centres, would that be a cause of concern?
cheers

 

[mandm65]

Hi mandm65,

I had a Vaillant registered installer around this afternoon to discuss what needs to be done to get my UFH into a separate zone and correct the mess left by the builders plumber. We briefly talked about low loss headers and he agreed it shouldn't be necessary on a single boiler setup. Also, I have a document from Vaillant (AIUFH2) showing how to include UFH in an existing Vaillant setup. While this also shows a low loss header, I queried this with Vaillant technical support and they agreed it isn't really necessary in a small setup like mine.

Regarding your setup, I obviously don't have the knowledge to suggest how it should be done and it appears you are using non-Vaillant wiring centres, but I just wondered if you were using a separate room thermostat for your UFH.

Thanks mate for your input/update, pleased that we can cross the LLH from the list, if i could have that document i would be grateful.
I am unsure if we are using separate room thermostat for UFH, unsure what role Evohome will be playing? At this stage all i know is the items listed above hence the reason for posting the items with the hope that expert here can see the list and advise if something is missing/left out or wrong?

Whats your next plan of action?

 

[Dan Robinson]

Evohome is fantastic, but you need to know your onions when specifying it.

The base pack is just that. ... A base pack.


For it to work with multiple UFH zones and radiators you'll need enough thermostats/sensors for each zone, and for more than one UFH zone, ideally you would have an hcc80. If more than 5 zones;, you'll need the expansion module too.

 

[Stephen7]

Unfortunately I am not ofay with the Evohome arrangement. The type of wiring centre should not really make much difference other that if you are using low voltage V main voltage.
I will see if I can dig out a standard hydraulic arrangement but as first mentioned I have not used the Evohome.

 

[St0rmer66]

ofay