Newish build (3 years) - Heating never right

LFCFan

Hi. We built a 2500 SQFT dormer which we finished in December 2007. We use Gas (LPG). We have underfloor heating downstairs with Stats in each room. Rads in the hall downstairs and rads in the bedrooms and landing upstairs. We also have Solar panels for hot water and a 300 litre tank.

Since we moved in the heating has never really worked great. When we have a few rooms with the UFH on, the rads upstairs never really get hot enough. The rads downstairs are usually okish but it's hit and miss. There is a master timer for the underfloor system that is supposed to control all the Stats but after many times trying to get it working, it just doesn't seem to be installed right (I'm thinking electrical problem as the electrician was a muppet). We've had the plumber back a couple of times but he seems reluctant to get too involved in trying to sort it out and we kind of ignored it since.

The boiler went on the fritz since we turned it on again since the weather cooled down. Boiler people came out and had to replace the pump and did a service on it. It's a condensor boiler. Since the service the heating is even more erratic. At times the rads hardly heat at all and for the most part, the hot water is not getting heated even though the pipe going into it is red hot. Also, the boiler is going on and off a lot more than I remember before the service and the temp reading keeps going up and down quickly.

Any advice, ideas on what we can get done with the heating? I want to get the builder back in but I want to have an idea of what can be done this time so we don't just get fobbed off again.

Cheers!

crosstownk

Have you enough water in the system? What does the pressure gauge read when the system is cold?

LFCFan

Right now it's at 1.3. For the most part it was around 1 up until the latest boiler service.

One other thing. Within the space of a few hours, the pressure in the solar system went from 2.4 to little over .5 - This all happened around the same time as the hot water stopped getting hot from the boiler. Could it be related?

ntpm

LFCFan wrote: »

Right now it's at 1.3. For the most part it was around 1 up until the latest boiler service.

One other thing. Within the space of a few hours, the pressure in the solar system went from 2.4 to little over .5 - This all happened around the same time as the hot water stopped getting hot from the boiler. Could it be related?

Boiler stat should be set around 70-80C... or so.

This should allow enough temperature for the radiators and hot water.
The underfloor heating manifold has a temperature sensor and bypass to maintain around 50C for its own circuit.

I would shut down/ switch off the underfloor stats completely and see if the boiler is able to maintain the temperature in the rads and then for the hot water cylider circuit.
Do you have indevidual pumps (or motorized valves) for the hot water and radiator circuits . These pumps should switch on and off via room stat and cylinder stat respetively.
The boiler should only switch on when there is a demand for heating from either underfloor rrom stat or radiator room stat or cylinder room stat.Check these controls.

The may issue with the average electrician is that they do not wire the boiler controls correctly.

Re: Solar pressure.

There is a posibilty that the solar system has a leak. Might need to get the solar guys in to check it.
(Coincident??)

LFCFan

ntpm wrote: »

Boiler stat should be set around 70-80C... or so.

This should allow enough temperature for the radiators and hot water.
The underfloor heating manifold has a temperature sensor and bypass to maintain around 50C for its own circuit.

Even with the boiler set around 50C it is eating gas at a ridiculous rate. I'll try the higher temp and see how I go with it.

I would shut down/ switch off the underfloor stats completely and see if the boiler is able to maintain the temperature in the rads and then for the hot water cylider circuit.

Even with the Rads and UFH off, the tank is still not heating up, despite the boiler working away. Dunno where the hot water is going. The pipe that is going into the tank gets very hot right up to the edge of the tank but the water isn't heating up. Weird.

Do you have indevidual pumps (or motorized valves) for the hot water and radiator circuits . These pumps should switch on and off via room stat and cylinder stat respetively.

There is one pump in the hotpress which is for the UFH circuit. This has always puzzled me as I was wondering how there is two separate circuits for the rads and UFH but only one pump? Is there a chance they've put the rads and UFH on the same circuit? If this was the case, what affect would it have?

The boiler should only switch on when there is a demand for heating from either underfloor rrom stat or radiator room stat or cylinder room stat.Check these controls.

Again, this was the case until the latest boiler service. Now it seems to go on and off a lot more often and the temp on the display goes up and down quickly.

The may issue with the average electrician is that they do not wire the boiler controls correctly.

Would not surprise me. We have lights wires arseways, sockets not put in where we asked and the main boiler timer wasn't even done till a year later as he 'forgot' to do it.

Re: Solar pressure.

There is a posibilty that the solar system has a leak. Might need to get the solar guys in to check it.
(Coincident??)

Will be giving the solar guy a buzz. Dunno how there could be a leak all of a sudden. System has been working perfectly for 3 years. Just weird how the solar pressure went down at the same time the tank stopped heating up correctly.

Anyway, cheers for the info.

ntpm

50C isn't hot enough for your hot water... should be at least 60-65C.
And 75-80C for rads.
This is why your boiler may be short cycling... turning on and off frequently.
The boiler is reaching 50C very quickly and then turning the gas off, the water is circulating and the boiler temperature is dropping quickly and switching on again... as the temp is only reaching 50C it is not on long enough for you to heat the water.

Reducing the boiler temp to 50C does not mean you will use less fuel.
It's like driving your car and your pushing the accelerator down hard then lifting off and pushing down hard again....... slow and steady is best!!


I would suspect that you have been relying on the solar for your hot water and as this may have stopped working it's highlighted the temperature setpoint is not warm enough.

just to note aswell.
The controls on your boiler may be why you are using more fuel than you need to... ( although underfloor heating is a bit of a gas guzler)

LFCFan

We were always using the boiler set at around 50 and until now there was never an issue with heating the hot water tank and for the most part the rads downstairs would get hot. There was always an issue with the upstairs rads (mainly the double one in the bedroom) not getting hot enough when the underfloor heating was on. I always got the impression that the UFH and rads were on the same circuit and the UFH got the hot water first and by the time it got upstairs most of the heat was gone out of it. Should the UFH and Rads be on different circuits and should there be controls to make it easy to turn the rads off/HW off and only have UFH heating on or just have HW on and everything else off or just have Rads on and everything else off? To me the whole systems seems awkward and a pain in the ass. Thanks again for the info!

Plombier

Some photos or a diagram of the installation would help.

ntpm

LFCFan wrote: »

We were always using the boiler set at around 50 and until now there was never an issue with heating the hot water tank and for the most part the rads downstairs would get hot. There was always an issue with the upstairs rads (mainly the double one in the bedroom) not getting hot enough when the underfloor heating was on. I always got the impression that the UFH and rads were on the same circuit and the UFH got the hot water first and by the time it got upstairs most of the heat was gone out of it. Should the UFH and Rads be on different circuits and should there be controls to make it easy to turn the rads off/HW off and only have UFH heating on or just have HW on and everything else off or just have Rads on and everything else off? To me the whole systems seems awkward and a pain in the ass. Thanks again for the info!

Sorry to say that you controls are definetly wrong.
They do not comply with building regs///
http://www.environ.ie/en/Legislation/DevelopmentandHousing/BuildingStandards/FileDownLoad,1631,en.doc
http://www.environ.ie/en/Publications/DevelopmentandHousing/BuildingStandards/FileDownLoad,19069,en.pdf

Part L Energy Efficiency.
Plumber / electrician/ builder have not installed the system correctly.

You must have separate temperature and time conrtol for hot water and heating circuits.
Heatimng circuits should then be zoned for separate temperature control ( and ideally time) i.e upstairs / downstairs.

Re underfloor and rads at ground floor level.
As stated earlier post temperature flow through UF if at lower temp and has separate pump and manifold and room stats.
You normally should have separate pump/motorzed valve for downstairs rads and a separate control thermostat.

This will ensure your boiler only runs when heat is required. BOILER INTERLOCK> PART OF PART L REGULATIONS.

Saving you money.

LFCFan

Plombier wrote: »

Some photos or a diagram of the installation would help.

Here's what we have in our hotpress and also the boiler and controls. Boiler was on the fritz again this morning with a red light :-(

yoshytoshy

LFCFan wrote: »

Even with the boiler set around 50C it is eating gas at a ridiculous rate. I'll try the higher temp and see how I go with it.

How are you calculating your gas usage ?

Nearly all modern boilers are modulating ,so no matter how low your boiler is turned down,it will initially use the maximum amount to get the heat up.

What you should do is take a reading of your meter ,before a two hour session at 50oC and after.
Do the same thing the following day and set it to 65-70oC and see what the difference is.

LFCFan

I've been on to the boiler company who repaired the boiler last week. They also did a servicing of the boiler at the same time. I am now getting a 79 error code which they tell me is a filter issue. Can anyone tell me if this is something that should have been found when they serviced the boiler last week? I would have thought the whole idea of a service was to make sure everything was working as expected and that it should work as expected for at least the next year? Also, how long should a boiler service generally take? The chap last week had to diagnose the problem we were having, figure out it was the pump, replaced the pump and did an annual service on the boiler. He was in the house for 45 mins. Does this sound right?

LFCFan

Ok, the latest now is that the filter was completely blocked because the system was never flushed and treated when it was installed. Beginning to wonder was anything done right when the installed the system :mad:

fat__tony

Judging by the photos and what you have said so far the entire system that has been installed is way over-complicated.