Jump to content

ASHP installation


Recommended Posts

I know this is how long is a piece of string question.....but I'm having to get more quotes on installation of the ASHP and Cylinder and I'm getting wildly differing quotes/estimates, I'm not ruling out that it might be me not explaining the situation.

 

Take out first fix plumbing, just to connect up the ASHP and Cylinder and associated bits and pieces what should I be looking at, I was expecting a cheaper install for pre-plumbed...

 

any help appreciated.

 

p.s If you are happier PM'ing, as opposed to posting on a public forum, that's cool too.

 

 

Edited by swisscheese
Link to comment
Share on other sites

Is this connect ASHP or connect the unit, controls and commission the complete system...?

 

If its a pre-plumbed cylinder then that’s a day, ASHP is another with a third for commissioning etc. That all assumes there are pipe stubs available etc. 

 

Day rates depend on where you are - £180 to £240 ish, shouldn’t be far out of the park. 

Link to comment
Share on other sites

It's the commission and controls which puts the willies up 'regular' plumbers I think. 

Any plumber should be able to open a set of instructions and plumb it in without issue, it's just they could be somewhere else in their comfort zone whacking 5 pipes up the bottom end of a combi and then just walk off.

I've yet to fit an ASHP TBH, but I wonder what the hype is all about? Do you need to be MCS to commission an non-RHI ASHP or just a competent installer ? 

Link to comment
Share on other sites

The controls are indeed different. For a system boiler you would expect a couple of motorised valves, a pump, a programmer a wiring centre and you would connect it the way you always had, and it would work.

 

I think the trouble with heat pumps, is they are all so individual, not much cominality between makes.

 

My own, the control box lives inside, connected to the heat pump with a 4 core cable.

 

As well as plumbing in the usual valves and pumps, mine has a flow switch to connect (it will refuse to run if there is no flow detected)  It also wants control of the immersoin heater in the HW tank, and  a few other details.

 

Nothing complicated but it needs a bit of reading of the manual and applying that.

Link to comment
Share on other sites

34 minutes ago, Nickfromwales said:

Do you need to be MCS to commission an non-RHI ASHP or just a competent installer ?

 

Neither.... it’s two water pipes, a power supply cable and the control wires. 

 

If the spurs and rotary isolator have been put in by the sparks then it’s a simple task to install. The manufacturer may say you have to be an accredited installer for the warranty however that was deemed illegal under block exemption so you just have to be competent in terms of connecting up - the downside is you may not have access to all the lovely technical compensation curve rubbish they band about that only their units will do. Most are either NV or 24v connections to the ASHP controls  

Link to comment
Share on other sites

1 hour ago, Nickfromwales said:

Do you need to be MCS to commission an non-RHI ASHP or just a competent installer ? 

 

32 minutes ago, ProDave said:

I think the trouble with heat pumps, is they are all so individual, not much cominality between makes.

 

I had a chap lined up to do the installation, the install gets MCS accreditation and RHI via a third party, he uses in these cases.

Essentially the third party do the maths ASHP sizing etc etc, and crucially supply the kit (I have also done the numbers via Jeremy's spreadsheets) and the Plumber installs what "they" say.

I was kind of happy with the quote the ASHP was a little more expensive ("MCS tax") but the Cylinder - Pre-plumbed, the price seemed very high, with very little detail available about performance.  In retrospect the the installation cost seems quite high now also.

The Plumber is "happy" installing this brand and specific cylinder; I question the cylinder price/performance/options, and the discussion has gone south, it's an all or nothing kind of deal.

So I'm considering other options - hence the question, the clock is ticking though.

The non-MCS/RHI route? It's proving difficult finding another local chap who as done ASHP or will quote with confidence.

 

 

Edited by swisscheese
Link to comment
Share on other sites

The company I used to work for (the bunch of crooks), decided to do heat pumps.

As we were going for MCS accreditation (already had the PV side of it), I had to do all the paperwork/calculations.

Was all pretty easy.

An experienced plumber, who had no experience of heat pumps, did the pipe fitting, an electrician did the wiring.

They never got it to work (I had left the company in disgust by then).

 

As far as I could see, there was nothing too complicated about the set up.  A largish thermal store, and expansion thingy or two, the ASHP, pipes to over sized (actually correctly sized) radiators and a simple thermostat controller.

Still fail to see why they screwed it up so much.

The room by room calculations and the 99% rule where easy to work out, the rest of the MCS side was just a paper trail really i.e approved kit, qualified people, willing to be inspected.

 

I think, and am willing to be corrected, that what scares people about plumbing and wiring, is really lack of product knowledge.  We often know what we want, but don't know if it exists or not, and what it is called.

Link to comment
Share on other sites

10 minutes ago, Nickfromwales said:

Let me put this another way,..can you plumb ? ( :ph34r: tidily and reliably). 

:D

I can do, and understand the basics, and give most things a "go",  even the wife describes me as "quite handy" :ph34r: when friends and neighbours have cocked up the DIY, however this is one of those areas where tiny mistakes could be magnified.

So on this occasion I'm looking for an experienced hand.

Link to comment
Share on other sites

A little bump/update

 

OK - I have possibly found a friendly no-nonsense Plumber would has done a number ASHP/UVC installations.

He is keen to stress, this has never included the commissioning of the System, this was always left to others.

What "exactly" does the commissioning involve?  Is this something I could do?  I know some on here have done the whole lot.

Does commissioning also mean UFH balancing etc for example.

Cheers.

Link to comment
Share on other sites

You will need to be able to read and understand the manual to set it up, things like heat compensation curves, setting the flow demand temperatures.  Better still would be for YOU to read and understand it, so you can fine tune the system and make it work as efiiciently as possible.   I would personally hate to have a system where I only know how to turn it on and off and nothing more about it.

Link to comment
Share on other sites

You can set a lot of those values via the regular interface, but there may be other settings hidden behind a service interface. Panasonic had to talk me through setting the internal pump speed, because it was set too low for our situation and changing it isn't in the installation guide or instruction guide that came with it. 

 

I also understand that there's a setting for having the internal pump come on for a few mins each day to stop it seizing during periods of non-use. I suspect it sitting still doing nothing for over six months last summer encouraged the pump failure that our ASHP experienced.

  • Like 1
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...