Jump to content

My Nightmare Heating System


newhome

Recommended Posts

29 minutes ago, Miek said:

 

No big deal TBH. the system will need draining, cleaning and recharging with new antifreeze. Hopefully there are no leaks form the overheating, but it's an easy fix really. Scottish Borders is too far for me I'm afraid ? 

 

 

Thank you. Solar install man implied that it would be knackered. Maybe that’s because he couldn’t be ar5ed with it. Good to know it might be able to be salvaged. 

Link to comment
Share on other sites

34 minutes ago, newhome said:

Thank you. Solar install man implied that it would be knackered. Maybe that’s because he couldn’t be ar5ed with it. Good to know it might be able to be salvaged. 

Well, maybe. It would seem unlikely that it's knackered. As in, beyond repair...  I very much doubt it. I've not heard of "jelly" forming in solar thermal systems, but maybe this is a loose term for degraded antifreeze? 

Link to comment
Share on other sites

Okay back to the boiler and tariff

 

You are on the Economy2000 tariff.  I had not heard of that one so had to do some research.

 

As you say that is a tariff aimed at electric storage boilers.  It gives you 18 hours of cheap rate electricity at the supply companies choosing (when they want to dump power) but with a guarantee that there will be no off period of more than 2 hours.

 

So first thing to sort out is the boilers controls.

 

You do NOT want a programmer on the boiler. There should be a high current switched supply that only come on during the 18 hours of cheap rate. I would expect this to be connected to a small consumer unit and the boiler fed from that.  So whenever the cheap rate is available, the boiler will heat the thermal store, only turning off when the tank thermostat says it is hot enough.

 

Sort that out FIRST so you always have a piping hot tank of water.  And as you are never more than 2 hours from a re charge, it should stay pretty hot all the time.

 

I don't see a tank thermometer in any of your pictures but just by feeling one of the pipes emerging near the top of the tank you should be able to get an idea how hot the tank is.  If it is not piping hot just about all the time, then sort that out first. Until you have a reliable constant tank of piping hot water, it is not going to work properly.   If you need an electrician to sort this, tell him it is just like wiring a big storage heater, the boiler should come on whenever the economy 2000 cheap rate is available and must be connected to the tank thermostat,

 

A statement in an earlier post worries me. "no hot water unless one of the pumps is running"  You should not need anything "running" to get hot water. As long as that tank is full of piping hot water, then domestic hot water should come out of all your hot taps, even if there was a power cut.

 

My suspicion at the moment is the boiler is only running and therefore only heating the tank when the UFH is on, which is wrong. As I have said before, charging the tank with the boiler is a completely separate thing to using that heat.

 

I see solving this as a 3 stage process.

 

1: get the boiler working properly so there is always a full tank of piping hot water:

 

2: let the plumbing experts pick the plumbing to pieces and sort out the controls for that.

 

3: sort out the heatmiser controls to get the heating working in all rooms.

Link to comment
Share on other sites

Re the solar installation. The parts were supplied by a company trading as Economical (http://www.eco-nomical.co.uk/). They sold relatively inexpensive Chinese evacuated tube panels, not the most efficient but perfectly OK, my system was mainly supplied by them.

 

If the system was turned off the anti freeze is likely to have degraded, can't say if it will solidify or not but even if it has it will only be at the top of the collectors which is a straight tube and should be easy to clear (apart from getting on the roof, of course!)

 

The pressure gauge reading is OK for a sunless day, when the sun comes out it should increase.

 

If the pump (the circular thing under the controller) is warm but no water is circulating it is possible that the pump is seized. Should be easy to fix if that's the problem.

 

Solar systems are fairly simple so there's no reason why it shouldn't be fixable.

Link to comment
Share on other sites

3 minutes ago, billt said:

The pressure gauge reading is OK for a sunless day, when the sun comes out it should increase.

I was kinda assuming the red pointer was set to indicate the maximum recommended pressure. No?

Link to comment
Share on other sites

13 minutes ago, ProDave said:

You do NOT want a programmer on the boiler. There should be a high current switched supply that only come on during the 18 hours of cheap rate. I would expect this to be connected to a small consumer unit and the boiler fed from that.  So whenever the cheap rate is available, the boiler will heat the thermal store, only turning off when the tank thermostat says it is hot enough.

 

Sort that out FIRST so you always have a piping hot tank of water.  And as you are never more than 2 hours from a re charge, it should stay pretty hot all the time.

 

I don't see a tank thermometer in any of your pictures but just by feeling one f the pipes emerging near the top of the tank you should be able to get an idea how hot the tank is.  If it is not piping hot just about all the time, then sort that out first. Until you hav a reliable constant tank of piping hot water, it is not going to work properly.

 

A statement in an earlier post worries me. "no hot water unless one of the pumps is running"  Yoi should not need anything "running" to get hot water. As long as that tank is full of piping hot water, then domestic hot water should come out of all your hot taps, even if there was a power cut.

 

My suspicion at the moment is the boiler is only running an therefore only heating the tank when the UFH is on, which is wrong. As I have said before, charging the tank with the boiler is a completely separate thing to using that heat.

 

The programmer for the boiler was put on by a local plumber about a year ago. The reason why is noted in the invoice I posted. I think he decided that as my bill was adding up and up and he was no nearer to understanding what needed to be done he would shove those controls on to at least let me control when the boiler was off and on. 

 

Hot water only arrives in the taps if the underfloor heating pump (electric) is switched on and running. If that’s off then no matter how hot the water in the tank is it doesn’t get to the taps and it’s cold only. Switch the underfloor heating pump on and hot water is delivered to the taps. That’s one of my biggest issues with the set up as if I leave the underfloor pump on all the time the hot water disappears out of the tank somewhere even if every room thermostat is switched off so I’m not sure where it’s going. That in turn means that I would need to have the boiler on 24 x 7 to keep the water hot which isn’t practical on this tariff or from a cost perspective either. 

 

At present the boiler is only on when the wall controller switches it on (and off). I set those times using the on and off times. 

 

 

Link to comment
Share on other sites

13 minutes ago, newhome said:

Hot water only arrives in the taps if the underfloor heating pump (electric) is switched on and running.

 

I think I know what he has done ..!!

 

Those tanks have a pair of pumps - one does the UFH and the other does the plate heat exchanger for the DHW which is triggered by a flow switch. When water flows through the switch, the pump comes on and the heat from the TS is circulated.

 

If he has mixed this up then you will get the problem you state. 

 

Ad @ProDave says, the heating boiler needs to be on its own timer (it’s only 0v dry contacts) but should be on its own supply. 

 

@Nickfromwales want to add anything ..??

Link to comment
Share on other sites

The boiler must be on whenever the economy 2000 rate is on. So ditch that controller. 

 

I suspect the power feed to the boiler is wired wrong and comes from a permanent supply not the E2000 supply.  Check your bills., you should be metered for peak, off peak, and E2000 as 3 items. The boiler should be the only one using the E2000 tariff.  Can you post pictures of your electricity meters and consumer units please?  This is problem No 1 to solve.

 

As @PeterW says the hot water in this case comes not from a simple coil but through  plate heat exchanger. The pump for that should turn on whenever a flow switch detects flow to the hot water taps, so that is more wiring that needs sorting out.,

Link to comment
Share on other sites

Hi Newhome. Just to help a bit a couple of bits of jargon busting might help. Fellow build hubbers, including me, need to explain the jargon.

 

Consumer unit = fuse box (most likely , near your meter.) This will have the supply companies switch that says cheap power is available and that should turn the boiler on although the boiler also seems to have its own timer.

0V dry contact also known as as a Volt free contact is just a switch.

 

  • Like 1
Link to comment
Share on other sites

20 minutes ago, ProDave said:

make and model of the electric boiler would be handy

 

It’s a Fusion 24kw 3 phase boiler supplied by The Electric Heating Company. I found an old photo with the cover off. 

 

I have the manual at home somewhere. 

 

 

F7F384A7-757F-4D47-8ECF-A4ED3EEA3EDC.jpeg

Link to comment
Share on other sites

5 minutes ago, Miek said:

That's the pressure reducing valve for the incoming cold I believe, 6.5 bar is a bit high, might need turning down

Just been on the phone to technical for some divine intervention ;)

Thats the PRedV ( pressure reducing valve ) that supplies cold water to the quenching coil at the very top, the one that has the silver corrugated pipe, which cools the tank down as stated in the red text I posted. Shouldn't ever have been fitted ! @newhome, can you confirm that you done have / never will have / dont have pipework run for a woodburner or solid fuel heater / boiler / other?

 

Oh, and its Fecked too. 

  • Thanks 1
Link to comment
Share on other sites

4 minutes ago, Nickfromwales said:

Just been on the phone to technical for some divine intervention ;)

Thats the PRedV ( pressure reducing valve ) that supplies cold water to the quenching coil at the very top, the one that has the silver corrugated pipe, which cools the tank down as stated in the red text I posted. Shouldn't ever have been fitted ! @newhome, can you confirm that you done have / never will have / dont have pipework run for a woodburner or solid fuel heater / boiler / other?

 

Oh, and its Fecked too. 

 

Never planned to have a wood burner or similar here. We thought that the UFH system would provide all the heating needed. I don’t think there are any pipes for that anywhere. 

 

 

  • Like 1
Link to comment
Share on other sites

17 minutes ago, newhome said:

 

It’s a Fusion 24kw 3 phase boiler supplied by The Electric Heating Company. I found an old photo with the cover off. 

 

I have the manual at home somewhere. 

 

 

F7F384A7-757F-4D47-8ECF-A4ED3EEA3EDC.jpeg

I have to go out now, I will look for the manual later (unless someone finds it first and posts a link)

 

Do you have a 3 phase supply? I assume so (still waiting for pictures of your meters and consumer units )  Otherwise 24KW (105A) is too much for a single phase supply

Link to comment
Share on other sites

1 hour ago, ProDave said:

The boiler must be on whenever the economy 2000 rate is on. So ditch that controller. 

 

I suspect the power feed to the boiler is wired wrong and comes from a permanent supply not the E2000 supply.  Check your bills., you should be metered for peak, off peak, and E2000 as 3 items. The boiler should be the only one using the E2000 tariff.  Can you post pictures of your electricity meters and consumer units please?  This is problem No 1 to solve.

 

 

 

I will take a photo of the meters when I am home. There are definitely 2 meters and the ‘heating’ meter is off if the boiler it switched off (red light comes on and stays on). When the boiler is running the meter comes on and red light flashes. 

 

The other meter is for ‘everything else’ as far as I know. There are definitely only 2 charges on the bill for units used which correspond to the 2 separate meters. 

 

Will post details once home. 

Link to comment
Share on other sites

5 minutes ago, ProDave said:

I have to go out now, I will look for the manual later (unless someone finds it first and posts a link)

 

Do you have a 3 phase supply? I assume so (still waiting for pictures of your meters and consumer units )  Otherwise 24KW (105A) is too much for a single phase supply

 

Pretty sure hubby said it was 3 phase whatever that means. 

 

 

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...