ASHP: lagging pipes in loft

gterr

Geotherm wrote: »

Hi Gterr.
Get the flow and return pipes outside insulated as much as possible as TiredGeek says. The black pipes, that you show in the picture, the one with the white connection on the external unit, is just power supply. The other one I cannot identify. as does not appear on the installer manual., can you trace where it goes??

Armaflex type O is recommended for the outside pipes

Thanks. Have done a temporary job on the pipes with some spare insulation. Very hard to get at these pipes in situ now. Good job I am a thin old wifey - no way husband could reach them in that narrow gap.

Have ordered some Armaflex pipe. I wonder if I should also get some Armaflex sheet insulation I can wrap around, given how hard it is to get into that gap and do a decent job. Of course it would be better if the pipes could be disconnected temporarily to get the insulation on. (And I am NOT up for this, though of late I've been thinking it might be better if I simply retrained from scratch as a plumber!)

No idea about that second black cable. It's covered with the same ribbed plastic that surrounds the other power cable. It enters the house through the wall at mid-height. No idea after that, sorry.

Will check meter daily now and see what we're using. It's milder today: 5 C outside. Honestly, if we're using 65 units per day when the temp hasn't dropped below zero yet I can't imagine what will happen when it gets really cold. We simply can't afford huge bills: both on pensions now.

Thanks for your help.

TiredGeek

gterr wrote: »

I am on a Scottish island

I'm being nosy again, which Scottish island?

Is there no way you can get the contractor back to look over the installation and fit the insulation correctly? I know the original plumber was sacked but it's not your responsibility to be doing these things (though I fully understand why you are 'cos you want it done right).

The Armaflex is much more flexible that the grey/silver stuff and it will be easier, but you'll probably have to slit it to get it over the pipes then tape up the joint to keep it in place. Like you said it should really be done with the pipes off but there's no way I'd suggest you did that.
It should have been done at installation, there's no excuse not to have done it, any plumber should know that external pipes get insulated. Particularly on a Scottish island

gterr

TiredGeek wrote: »

I'm being nosy again, which Scottish island?

Is there no way you can get the contractor back to look over the installation and fit the insulation correctly? I know the original plumber was sacked but it's not your responsibility to be doing these things (though I fully understand why you are 'cos you want it done right).

The Armaflex is much more flexible that the grey/silver stuff and it will be easier, but you'll probably have to slit it to get it over the pipes then tape up the joint to keep it in place. Like you said it should really be done with the pipes off but there's no way I'd suggest you did that.
It should have been done at installation, there's no excuse not to have done it, any plumber should know that external pipes get insulated. Particularly on a Scottish island

Hi there,
Please excuse this long post: a LONG RANT follows:

We are on Skye. This nightmare has been going on for 18 months now.

We never had a proper handover of the heating system when the newbuid was finished, so never got to ask questions about the setup. We were just told to 'leave it as it is'. Found straight away that the rads never got more than tepid, because it had been set up for U/F heating only, not U/F plus rads. Adjusted the heat curve as instructed following emails to Worcester (to suit the mixed installation), only to find huge electricity bills (over £10 per day, during what was a mild winter.) Did some more research myself and adjusted heat curve down again to what it should be (V=22, H=55 for a mixed system). Still expensive, but manageable. Between August 25th and October 20th we used an average of 35 units electricity per day. House is all-electric but even so! Now we are up at about 65 units per day.

Original plumber and main contractor claim the system was commissioned by Worcester, yet we never received any commisioning paperwork. Main contractor got us a new plumber who said he would do a proper 'first time' commissioning, and he was MCS registered so we could claim the RHPP. To give him credit, he did spend ages on the phone to Worcester technical guys, because he didn't know their kit, but in the end he adjusted nothing, was unable to asnswer any of my questions, failed to spot the lack of lagging (he never went up in the loft or outside), and sent me a bill for £695 which I haven't paid because we STILL don't have any paperwork, which I understand we would need if ever we wanted gto claim RHI.
Keep phoning him to remind him of this, but it's been months and months now, and I've pretty much given up.

This plumber suggested I call out Worcester tech to replace a pump inside the HWDU which was whining a little bit, mainly in order to have a tech guy over to check it over. The part has now been replaced, though the guy said it probably wasn't faulty, but the guy who came out to do it was not the regular Worcester tech and gave me no advice whatsoever, and i certainly knew more about the system than he did.

I think I probably know the Worcester users' manuals off by heart, but I'm not a plumber so I'm limited in what I can ask the Worcester techincal guys, since they respond with wanting to know details of our set-up that I simply can't answer.

The system is definitely compromised, yet we don't ask much of it. In an attempt to economise on electricity I have turned down the individual room stats (we have timer/stats in every room). We are only asking for 19 c in kitchen and dining room, 21 C in lounge (all backed-off 1 or 2 degrees overnight and 1 degree during middle part of day) and 15 C everywhere else. At this time of year the system can't bring the lounge back up to 21 C in the evening (it makes it to about 20C or 20.5, so if we want to be more cosy we have to light the stove.

Upstairs we have the bathroom rad on all the time (because first plumber said if we didn't the pump would burn out) one bedroom rad on half way, and landing rad on low. That's it. Rads are on the timer: 2 hours morning, 5 hours night time.

I think the system must run pretty much continually. Certainly, water circulates between the HWDU and the primary store most if not all the time.

I feel dreadfully let down, but I am not clear what to do now. There seems to be little point in getting back the second plumber (except to get the commissioning and mCS paperwork off him), and no other plumbers on the island do heat pumps of any make. I might be able to find the first plumber - who was sacked but who does at least know what he's installed - but I don't have much confidence in this.

What we really need is an engineer who knows the Worcester pumps and could check our whole setup. It could be something as simple as a setting that's wrong (though I doubt it). I do not know about seeking redress. It's been 18 months since we moved in here so I'm not at all sure the main contractor would step up.

I just need to get this fixed. When we had this house built we were willing to pay extra upfront in order to have lower bills goung forward - since we are on a low income. I can't cope with this huge electricity usage, and all the worry. Right now I'm tempted to have the whole thing ripped out - which is obviously stupid but I can't see an end to this.

Anyway, I've enjoyed the rant!

Cheers,

lovesgshp

Gterr, can you give me some time to look into the problem, as I mainly deal with the IVT gshp units, but I have the info on the ashp units as well. I may need some technical info, but will let you know the settings to look at for them. Sure we can get somewhere with a solution.

lovesgshp

Have you got a copy of the commissioning report, as this has quite a lot of info on it. Plus can you give me the model of the unit?
Also can you check the alarm menu for any faults and let me know

gterr

Geotherm wrote: »

Gterr, can you give me some time to look into the problem, as I mainly deal with the IVT gshp units, but I have the info on the ashp units as well. I may need some technical info, but will let you know the settings to look at for them. Sure we can get somewhere with a solution.

You are very kind, Geotherm. Thanks. You did try to help me once before, if you remember?

(Don't suppose you would fancy a free holiday on Skye? We have a holiday cottage nearby. Could probably manage your flights too!)

A couple of things that I may have done which might have made things worse:

1. Since we have timer/stats in every U/F zone (every room except bathrooms) I have reduced the 'room temperature influence' to zero. i.e. we now depend on the outside temp sensor and the individual stats, not the single indoor sensor (which is in a stupid place anyway).

2. To try to economise I have turned stats in unused rooms, corridors etc to 15 C. I have also turned off the downstairs bathroom U/F coil by screwing down the red cap thing on the manifold. However, I realise that the U/F coils serving the warmer rooms will probably pass through these cooler areas on their way to the warmer rooms. Could this be hindering things and actually be wasting electricity, not saving it?

Many thanks indeed for your time.

gterr

Geotherm wrote: »

Have you got a copy of the commissioning report, as this has quite a lot of info on it. Plus can you give me the model of the unit?
Also can you check the alarm menu for any faults and let me know

Hi,

I don't have a commisisoning report. (I seriously doubt that one was ever done, by either plumber). I do have a Test Report for the heat pump and another for the indoor unit (HWDU), if that's any use. I guess these came with the pump when new. Nothing interesting (no numerical values) for the HWDU. The other test report gives numbers for things like motor cut-out setting, high pressure trip setting. Let me know if you want these, but I'm guessing these are not what you want.

Model: Worcester Greensource 9.5 230V for the heat pump,
Worcester HWDU-151 for the internal unit.

Will inspect alarm log.

Cheers

albyota

Getrr, what size is the house....M2 and what is the greensource heat pump model no.?

As much info as poss please

lovesgshp

Hi Gterr. Would love to come over and try to help sort the problem out!!
Let's try remotely first and build up the information on the system. The initial setup looks ok from your diagram. I cannot remember what we discussed before, unless you emailed me on my business account, whereas I can look up the conversation.
I do need to know any alarm logs, as these sometimes pinpoint a solution.
With 1) the outside air temp could be making the system run longer,as it alters the heating curve higher. If the radiators have not got bypass valves on them, then this could be restricting the heating flow.
2) If you turn off the underfloor coil, then that should not make any difference to the other rooms, as it should be only that room affected.

gterr

Geotherm:
Alarm log:

A cluster of "Tripped motor cut-out fan" and "Tripped motor cut-out compressor or phase fault" for the period 11/04/2011 to 11/05/2011 when we had a problem with new appliances tripping out and the electrician was investigating. Nothing at all since 30/05/2011. (Actually, come to think of it, I may have had to reset the clock at some point because it was reading the wrong time and date, so the dates of those alarms in the log may be wrong.) Anyhow, no recent alarms.

Albyota:
House is 142 square metres. Detached, timber frame with blockwork outer skin. 1.5 storeys (2 beds and a bathroom upstairs, utility, bathroom, bedroom with en-suite, kitchen-diner and lounge downstairs.
Greensource 9.6kw air-to-water pump with the internal HDWU and Rego unit.

Many thanks for your efforts!