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Self install, wise or otherwise ?


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On 18/01/2023 at 12:27, Post and beam said:

A question for the experienced people here.

 

Is it reasonable to expect that an ASHP installation for a new build would include some kind of hot water tank/cylinder.

 

The reason for me asking is that if i have been quoted for a system i expect it to be for the 'system'. And all that that would typically include.

 

Depends what was asked... If you said "Can you specify me a heat pump for heating in a new build" then it wouldn't include a hot water tank as that's not what you asked. It is possible for new builds to just have a hot water tank with a heating element and a totally separate heating system.

 

As has been said the prices quoted are crazy, they obviously don't want/need the work, or think that you will be a massive hassle to them and have priced as such.

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To put it in Context we had a quote [early 2020]  from "that company" for ASHP including NIBE F2040, and kit  etc.  for 8.2k [No VAT]

We went with another company whose equivalent supply [Aerotherm 7kw plus] and kit .  was £6.5k [No Vat]

I could have bought the same stuff from City Plumbing for less Inc VAT [even less if we'd shopped around.] , [and claim VAT back later] - but we got sucked into the whole RHI scheme.  

 

 

 

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So cost update as I been shopping, cost includes a 2 zone UFH manifold and 100m of 16m pipe. All pricing include vat and delivery.

 

New Maxa 6kW heat pump (same as Viessmann, Vitocal-100 normally £4k) £1300

28mm Fill flush manifold and filter ball valve £78

Computherm thermostat £50

Manifold and UFH pipe £208

Wiring centre, expansion kit, 2x auto vent valves £86

AVM feet and flex hoses £147

Viessmann 1" Flow and return isolation valves, electric meter and isolation switch £158

28mm 3 way valve £59

 

Total £2086.

 

Only have add inter connection piping.

 

Hope this give people an idea of what the costs are or can be to do it yourself.  Will do all plumbing myself, will need an electrician for a day.

 

 

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If it's a low temp dwelling, then the cheap manifolds usually only feature a regular TMV with a lowest setting of 30oC, which choke to death at that setting. I'd allow £500 for the Ivar pump / blending valve + Komfort manifold.

So above + £300 basically. Still a lot of DIY bang for the buck!!

 

@JohnMo could you post a link to that ASHP please? Just interested to read up about it as it sounds VERY cheap.

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36 minutes ago, Nickfromwales said:

If it's a low temp dwelling, then the cheap manifolds usually only feature a regular TMV with a lowest setting of 30oC, which choke to death at that setting. I'd allow £500 for the Ivar pump / blending valve + Komfort manifold.

So above + £300 basically. Still a lot of DIY bang for the buck!!

 

@JohnMo could you post a link to that ASHP please? Just interested to read up about it as it sounds VERY cheap.

Very cheap considering they are exactly the same pump as the Veissman Vitocal 100-a 

@JohnMoyou were right I’ve had it confirmed by Veissman UK 

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15 hours ago, JohnMo said:

So cost update as I been shopping, cost includes a 2 zone UFH manifold and 100m of 16m pipe. All pricing include vat and delivery.

 

New Maxa 6kW heat pump (same as Viessmann, Vitocal-100 normally £4k) £1300

28mm Fill flush manifold and filter ball valve £78

Computherm thermostat £50

Manifold and UFH pipe £208

Wiring centre, expansion kit, 2x auto vent valves £86

AVM feet and flex hoses £147

Viessmann 1" Flow and return isolation valves, electric meter and isolation switch £158

28mm 3 way valve £59

 

Total £2086.

 

Only have add inter connection piping.

 

Hope this give people an idea of what the costs are or can be to do it yourself.  Will do all plumbing myself, will need an electrician for a day.

 

 

 

hats off to you, good going sir.

 

Just had a look at the 9kW one myself as that size fits my needs, I'm a bit green, but handy and confident, the install instructions are in bloomin italian though...  Scratch that, found the veissman installation manual

 

Edited by crispy_wafer
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17 hours ago, JohnMo said:

So cost update as I been shopping, cost includes a 2 zone UFH manifold and 100m of 16m pipe. All pricing include vat and delivery.

 

New Maxa 6kW heat pump (same as Viessmann, Vitocal-100 normally £4k) £1300

28mm Fill flush manifold and filter ball valve £78

Computherm thermostat £50

Manifold and UFH pipe £208

Wiring centre, expansion kit, 2x auto vent valves £86

AVM feet and flex hoses £147

Viessmann 1" Flow and return isolation valves, electric meter and isolation switch £158

28mm 3 way valve £59

 

Total £2086.

 

Only have add inter connection piping.

 

Hope this give people an idea of what the costs are or can be to do it yourself.  Will do all plumbing myself, will need an electrician for a day.

 

 

Bargain…. You’ve beaten me by about £1k, although I’ve got an unvented cylinder in my random pile of eBay parts.

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  • 3 months later...

Update

After getting lots of other jobs done, got back to the ASHP install. Ended up spending about £2500 all in. I didn't have a cylinder to purchase.

 

Basic description of the setup.

From heat pump to house is run in 28mm a mix of copper and Hep2O. The summer house is about 8m from the 28mm pipe run and is run in 15mm Hep2O pipe, the UFH has 2x loops 50m long each. This system has a 2 port valve that closes on a DHW cylinder call for heat and when thermostat in summerhouse is hot enough. The summer house is not setup to call for heat.  Once the 28mm pipe gets into the house it is reduced to 22mm and via a 3 way diverter, goes to the UFH manifold where it is distributed around the house via 7 loops. The cylinder is fed via pre existing 22mm Hep2O piping originally installed for the gas boiler to UFH manifold these pipes are around 8m long. Calculation shows the pressure drop for cylinder heating are way to high.  To fix this I added a pump in to the return pipe from the cylinder, the pump is powered on, at the same time as the 3 way valve is powered to move to 3 way valve to DHW heating. It seems to work and gets the flow back to 1m3/HR.

 

Had the Maxa heat pump running today. Very quiet in operation, have set to run on WC, and it is basically running on min temperature of 25 deg. Also tried it on cylinder heating, the heat output slowly ramps up until it get to 60 deg flow temp, after this it shuts down.

 

Have set up to run without any pumps or mixer valves on the two UFH manifolds, one in the house and the other in the summer house.

 

Bit of fine tuning to do tomorrow. And loads of pipe to insulate.

 

Photo showing the return DHW pump set up, pump temporarily propped up in a surface mount switch box. Wiring to pump and 3 way valve needs to be clipped in place tomorrow. UFH wiring centre is no longer used as the house is run on a single zone. The thermostat controls the heat pump directly.

IMG_20230503_081812.thumb.jpg.98af7c25c5645bcf80bf71f05f84051c.jpg

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Great stuff!

 

I'm still collecting bit's for my install, I've spent a bit more than you though (just shy of £4000 inc VAT at the moment for the ASHP/Cylinder install) as I purchased a matching 250l pre plumbed cylinder to go with the grant hp.  I cant wait to get cracking on it, however I've got many other jobs to get done first.  So that's holding me back a bit.  Rather gutting, but  I saw a Grant 6kW, and 180l cylinder go on Ebay this week for £820.

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On 07/05/2023 at 21:43, eniacs said:

More photos needed!

 

Im mid way through doing the radiators and house piping upgrade. Yet to site the heat pump and havent even bought a cylinder yet.

Some photos

 

Heat pump, with electrical isolation, heat pump in front of a log shed, feed and return pipes and electrical cables go towards back of shed, and turn 90 degs into my water shed (insulated pallet shed where my water treatment is for the well.

 

 

IMG_20230510_152409.jpg

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Inside water shed, expansion tank, 2 port actuator valve to summer house. Closed on a DHW heating demand and via a thermostat. The pipes also go to the house, underground, with 25mm insulation within 110mm double wall flex duct (one per pipe). The rest of the electrical stuff is

1. House wireless thermostat (x1) receiver, it switches the heat pump off if heating satisfied.

2. RF switch from from cylinder thermostat feeding 3.

3. DHW control relay, controls summer house 2 port valve and sends signal to heat pump for DHW heating 

4. Summer house thermostat, opens and closes 2 port valve, if DHW is not calling for heat

5. Wiring centre

6. Electric meter for ASHP

7. Heat meter

 

IMG_20230510_152346.jpg

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On 10/05/2023 at 15:46, JohnMo said:

Inside water shed, expansion tank, 2 port actuator valve to summer house. Closed on a DHW heating demand and via a thermostat. The pipes also go to the house, underground, with 25mm insulation within 110mm double wall flex duct (one per pipe). The rest of the electrical stuff is

1. House wireless thermostat (x1) receiver, it switches the heat pump off if heating satisfied.

2. RF switch from from cylinder thermostat feeding 3.

3. DHW control relay, controls summer house 2 port valve and sends signal to heat pump for DHW heating 

4. Summer house thermostat, opens and closes 2 port valve, if DHW is not calling for heat

5. Wiring centre

6. Electric meter for ASHP

7. Heat meter

 

IMG_20230510_152346.jpg

25mm wall insulation on standard 28mm hep, inside 110 ducting? That's certainly tempting compared to the insulated twin I was looking at, from a £££ perspective. Were you concerned about heat loss?

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1 hour ago, HughF said:

Were you concerned about heat loss?

With the duct and insulation you also get an air gap, which adds to the insulation as the outer duct/pipe is sealed at both ends, so you also get an unventilated cavity.  When you look at the details of pre-made underground insulated pipe the insulation is not really that good and want loads of £ for it. 

 

Looking at Rauthermex 32+32/111mm DUO Pipe, you have 2 x 32mm pipe in a 111mm pipe, the insulation may be slightly better but it's not very thick.

 

I have one 28mm pipe in a 110mm pipe the rest is insulation. So overall I think it's cheaper and better quality than the ore made stuff.

 

The shed is also well insulated, basically pallets full filled with rockwool. Vapour control layer internal and breather membrane external.

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