Underfloor heating problem

daludo

Hi folks

I have underfloor heating downstairs and rads upstairs. House built 2004 with heatpak oil boiler.

My question is,does a typical underfloor heating system need some kind of service??I think only 2 of my zones are heating eventhough room stats say different. Some rooms floors def feel warmer than others. All actuators etc seem fine and pipes feel warm leaving the manifold heading out along the floor. Is it possible that there's a blockage or some other issue?

Regards

Daludo

zg3409

Get a portable thermometer and check actual temperature in each room. A cheap digital one would work ok. The floor only gets warm when the room temperature is low and it's actively heating. Without knowing if room is the temperature expected we won't know if room heating is working. At the moment outside temperatures are 2 degrees and you inside temperatures are 20 degrees. All heating systems will be struggling to keep badly insulated houses warm and some rooms may have vastly different temperatures depending on radiators and insulation. There might be an issue but it might be that rooms are close enough to intended temperature.

Wearb

Do you have flow meters on the underfloor loops?

daludo

I do yeah

daludo

Wearb

https://www.boards.ie/discussion/comment/118233280#Comment_118233280

Turn all of your zone thermostats up to about 30 (well above room temperature) and let us know the readings from the flow meters. They should all have a good flow when all being called for heat.

daludo

All stats up to 30deg.see attached result on manifold. How does that look??

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20211128_124612.jpg

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John.G

Can you make out what each flowmeter is reading? they move downwards with flow, each should have a flow rate of ~1.5.2.0 LPM.

Wearb

Dont forget to return your stats to the original settings.

I'll try and see if I can understand those flow rates later. There are other lads on here more knowledgable on this stuff than me and perhaps they might comment on those flow rates.

On a quick look, it seems as if not all zones calling.

daludo

Another update, all zones calling for heat now,actuators opening. Flow rate of 4 on two zones. All other zones are at zero..The zones with a flow rate of 4 are actually the only two warm rooms!!!!I'll attach a pic of another stat attached to the uf pump.

16381056299541907284284962516299.jpg

Wearb

4 is normally way too high, but they might come back once you get the other zones working. You probably need a plumber in to diagnose the problem with the broken zones.

daludo

I'm presuming it couldn't be the pump as there are two zones working?

Wearb

Probably not, but other problems like thermostats, valve heads/bodies, etc, need to be checked.

Ardabawn

sounds like the actuator heads positioned on the return manifold are not operating correctly or the pin in the manifold, which these actuators open and close are stuck in the closed position.

pop off one of the actuators on a loop that's not working and press the pin underneath. if it's stuck in the off position, it won't press down any further.if it's not stuck closed it should push down and spring back up. (you'll probably need a spanner or pliers to press the pin)

daludo

Problem solved,pump was not working properly, which explains why only the two zones nearest the manifold were working. In fairness I got 18 years out of that pump!!!thanks everyone for your help on this

poker--addict

https://www.boards.ie/discussion/comment/118258793#Comment_118258793

I’m having some issues.

I noticed tonight that despite actuators showing blue (calling for heat), the pins on 3 pipes were only half up, and in one case not up at all. 1 seemed to be stuck half open and seems to be acting normal now that I have “unstuck” it and moved it up and down a few times. The other 2 of them feel “loose” like no pressure against them, indeed one wont even stay up when I pull it up.

air?

poker--addict

Any ideas?

serox_21

Can you close all other loops and leave on only the problematic ones. Then check the pressure, might be air in those loop.

poker--addict

thanks serox, will try that, have one pipe fitting if i need to push water through, but waiting on second one.

The circulating pump beside the manifold has many many settings, how do i know if it should be faster or slower. It has a digital screen and seems to range from 2 to 19 but has a few other options too.

serox_21

I think the pump speed should be adjusted to sustain the flow rate for all loops. Depending on the loop length the flow rate should be adjusted individually.

May be the pump has an auto setting. Try that one first.