So I’ve started thinking seriously about a self install and I’ve come up with a roadmap.

1. check existing pipework can handle the flow rate.

2. Perform a hear loss on my house.

3. Assess the radiators.

4. Compute pressure loss of the index circuit with existing pipework.

5. Work out what needs to change with existing pipework and radiators.

Once Ive done that first pass, then I’ll look at siting the pump, drainage, noise assessment and then apply for planning permission (but Im hoping they change the 1m boundary rule by that time!)

Whilst all this is going on, I’ll be doing the Heat Geek courses to help me understand more about the design!

Im also going to look into an MCS Umbrella signing off my installation, so I can take advantage of the BUS grant.

I’ve completed the first step, checking the flow rates will work, and it looks like I’m mostly okay. 

You can check out my video - Road to a Heat Pump - Checking my existing plumbing - Part 1

Nice video Tom. Well explained 😁

Thanks!

Very interesting, @tomasmcguinness. You're a step or two ahead of me, I think. Can I suggest care with references to DeltaT in your videos, though, to avoid potential for confusion; suffix with 'boiler', 'radiator', or whatever.

@ianmk13 Thanks. I'll bear that in mind in future videos. I know after looking at that against, that my explanation of a few things was off. Learning never stops!

The work continues! 

I've finally finished doing my simple heat loss calculation. Long delay getting this video out as I was doing the Heat Geek Mastery course. 

In this video, I do a simple explanation of heat loss, how I approach it and then I run through all the numbers for my house.

It shows my heat loss is going to be around 7kW, but I need confirm this by using a professional tool (which will be my next video!)

@tomasmcguinness Have you been able to perform any sanity check on that figure?  I'm thinking of the 'divide annual gas consumption by 2900' rule of thumb, for example.  My own heat loss calculation that I did last year came out at around 13.5 kW but I tended to err on the pessimistic side.  'Air change' seems to have a big effect on the numbers, for example. The above rule of thumb using several years' worth of data resulted in a figure of 9-12kW. The higher figures were from years when we were at work during the day and I was running the heating largely for the two periods we were home and awake, so probably very inefficient.  I've now downgraded my guesstimate to 10-11kW based largely on what I have gleaned from this forum. I've been monitoring my heating closely this heating season but there have been too few really cold days here in Buckinghamshire to make any helpful conclusions.

I’m in the DIY camp, completed the install last September and it has been running 24/7 since then.

Slightly different choice of install (15m up the garden from the house) and choice of emitters (rads and fan coils), but it works nicely.

I spent a bit mind you, close to £10k for all the parts for what ended up a completely new system, even down to changing all the primaries.

Heat loss and rad sizing were done with the freedom heatpumps spreadsheet and cross checked with heating engineer.

Another in the DIY camp. New build that had UFH and a combi boiler. Swopped over to ASHP.

My main takeaway was question every component you install and ask do I need it? Keep it as simple as possible.

My system has a few strange things but mostly because of existing pipe work and location of equipment. And the same ASHP is shared between house and garden room, one with UFH the other with fan coil. But essentially it's a single zone with a garden room and house, UFH manifold without pump or mixer or actuators. A cylinder with big coil and 3 port mixer. Not much else.

@johnmo sounds great. Could you share some photos?

Maxa R32 6kW ASHP, run on min hertz setting. Very quiet even doing DHW. Run cooling mode in summer through UFH and fan coil.

Piping at UFH manifold. 3 port valve and pump (to cylinder) controlled by ASHP. Additional pump required due to the long distance between ASHP and cylinder.

Cylinder 210l slimline. 3m² coil.

It’s been a while, but I have completed another step! 

I used the tool HeatPunk to perform a room by room heat loss and to give me a heat pump recommendation. 

Air changes made a big difference and I ended up with figures between 6.5kW and 8.5kW heat loss. 

I still reckon my heat loss is around 7kW based on my heat meter measurements, but it’s clear there is still a big margin of error!!

You can watch the video here

Using HeatPunk to do a Room-by-Room Heat Loss - My DIY Air Source Heat Pump journey