Underfloor heating problems

[justalex81]

the flow and return temps look a little low on the manifold. Do you know how far apart the loops are? i hope they're close together with it being 12mm pipe!

 

[paulmul]

My money goes on blending c
Valve cack. Trv type manifolds are utter rubbish . Take off the trv head bet after two hours it's hot. Also massive load. 22mm primaries? Boiler looks nice.

Your return running at 35 o tad low? Turn trv up to 4 or 5

I turned the TRV up to 4. A couple of hours later the inlet is at 46 degrees and outlet is at 42. 35 is lower than it usually sits so I'm guessing the moment at which I took the photo was just before the boiler kicked in or just after a loop opened that had been off for a while, adding cold water to the system?

Are primaries the main pipes to & from boiler? If so, yes, 22mm.

Also thanks for confirming what I suspected that at least one component of the system was crap!! The manifold was installed in 2007 and I've no idea who did it - it wasn't the plumber who did all the work in summer 2013.

 

[paulmul]

I dont like the angle of the flue on the boiler, but that could be an optical illusion with the photo.

I think (hope!) it's the photo. It's basically out the top of the boiler then straight out through the wall at 90 degrees.

 

[paulmul]

the flow and return temps look a little low on the manifold. Do you know how far apart the loops are? i hope they're close together with it being 12mm pipe!

Thanks - the plumber had said to set it to about 40 degrees on the inlet. As mentioned above 35 is lower than average on the outlet. I've turned it up a bit now.

I should also clarify the "20 minute pause" thing is EXACTLY every 20 minutes from the time I first turned on the main switch to the whole heating system. It's not that the system reaches its preset temperatures every 20 mins or so. I can set my watch by it. 10 past the hour, half past, 10 to the hour..... I'd love to understand what's going on with that!

 

[paulmul]

the flow and return temps look a little low on the manifold. Do you know how far apart the loops are? i hope they're close together with it being 12mm pipe!

Sorry, should also have answered the question! I'm not sure as the loops were laid 5 years before I first saw the house. The floor DOES get warm (more noticeable in some rooms than others). When walking around without shoes on it feels fairly consistently warm to my feet which I hope is a positive sign.

 

[justalex81]

that is a positive sign. Any idea on how long each loop is? if your flow meters weren't set up correctly you might be wasting a bit of energy but not massive amounts.

how much does 700-800L of oil cost?

 

[paulmul]

Again, no, I'm not sure as I effectively inherited it some years after the loops were installed. Some must be reasonably long as the whole house is 3360sq ft but downstairs is bigger than upstairs (sunroom and utility have nothing above them), so must take a reasonable amount of loop just to reach some parts. Flow looks to be set a bit higher on the ones further away - is that would you'd expect?

Oil was 57p/litre the last lot I got in December (£513 for 900 litres). I can't get mains gas where I am as I'm in a fairly rural location off the mains gas network.

 

[Ermintrude]

Once the floor is warm and house in use your consumption can be measured.

Reads like flow and return wrong way round on manifold.

That's why heat miser pipe stat thinks it's all satisfied .

 

[SimonG]

I think (hope!) it's the photo. It's basically out the top of the boiler then straight out through the wall at 90 degrees.

Do you get water underneath the flue outside?

 

[paulmul]

Once the floor is warm and house in use your consumption can be measured.

Reads like flow and return wrong way round on manifold.

That's why heat miser pipe stat thinks it's all satisfied .

The flow is USUALLY reading a higher temp than return. Sometimes return shows higher temp by 5 degrees or so. No idea why! Right now it's 43 on flow and 40 on return.