Opprtunity 'Oop Norf'

[Worcester]

I have a contact up doing a self-build project looking for a competent installer, Anyone up for it?

PM me and I'll forward your details to him, Her's his draft spec and he's open to professional advice.

The plumbers forum (full of plumbers that haven't a clue about integrated renewables) have got there attitudes so far up their ***e that he's asked me to recommend someone

he's already done some of it

Domestic Plumbing System:

Background
A timber frame, 3 storey, 5-6 bedroom house in the course of construction, currently at first fix stage. The house is located in the North East, near the North Pennines, high up at 300 metres (1,000 ft). It gets quite cold and windy and there are periods when the electric is out. The fabric will be well insulated, U-Value wise:

Walls 0.12 w/m2K
Roof 0.15
Ground Floor 0.12
Windows 1.4-1.7

SAP Assessment
A desktop SAP calculation has predicted:

Final SAP Rating of 89 (Band B)
Space Heating 21,568 kWh/year
Hot Water 2,677 kWh/year

It just misses out on Band A as it is marked down for having a MHRV system. If we didn’t install that and just fitted normal extractors, it would be Band A. That’s how stupid SAP is.

Heating
Water underfloor heating on the ground floor only within a flow screed and ceramic tile finish.

A whole house Mechanical Heat Recovery ventilation System (MHRV) has been fitted as part of the first fix – solid spiral ducted. This is a Helios KWLC 650/WW with a water battery heater fitted. This will top-up the incoming supply air if the heat exchanger cannot fully heat.

Bathroom Towel Rails
These have been first fix plumbed in 15mm copper. These will provide the heat needed in the bathrooms to replace the air extraction side and also balance some heat around the rest of the house via the MHRV.

Hot Water Supply
Required to:

Ground Floor Kitchen, Utility and Cloakroom WC
First Floor Main Bathroom and En-suite
Second Floor Bathroom

Some of the runs are 15-20 metres, so thinking was to have a hot water loop to minimise draw off waste.

Solar Thermal and PV
2 x 10 Navitron 70mm solar thermal tubes fitted to south west roof @ 38 degree pitch. To be plumbed in.

4kW solar PV panels fitted to south west roof @ 38 degree pitch. Immersun unit to be fitted to divert excess generation to thermal store immersion.

Proposal
Natural gas is available, although not fitted as yet.

Thermal store (size tbc) to be installed in garage and to take solar inputs and feed all hot water needs. Gas boiler will top-up if needed, although it is hoped the store can feed most needs with 2-3 days of stored reserve to see us through the cold snaps or when solar feeds are poor.

Thermal Store Inputs:
1. Solar Thermal (2 x 10 Navitron 70mm tubes)
2. Excess Solar PV via electric Immersion.

Thermal Store Needs to Feed (via boiler booster if needed):
1. Hot Water Loop to all tap outlets.
2. MHRV Water Heater Battery.
3. Underfloor Heating System.
4. Bathroom Towel Rails

Gas Boiler
This will top-up the thermal store (if needed) and see us through cold periods. The Rinnai booster boilers, which only heat up water supplied via thermal store if needed, are of interest. Would prefer a tried and tested boiler if this can fit in with the system design.

 

[Gavin A]

I'd expect we'd be up for that - got an additional renewables trained plumber coming on board in 2-3 weeks, so I don't have to do it all myself.

Any idea what's actually already installed?

If UFH ain't in yet, then I'd expect mr Dansk would sort that side of it out.

It also would sound perfect for a little heat pump, and / or wood burning stove with back boiler instead of the gas boiler, but obviously that depends on the scope for chimneys, space etc

I'm a little concerned about some of what's written about the MHRV re recycling heat, I've seen a few try this and come a cropper with it, but could add an inline water to air heat exchanger fed from thermal store - well, if I can remember where I nearly sourced one before for a client that fell through.

Please fire the details across and I'll get in touch.

 

[JulianC]

I'm a little concerned about some of what's written about the MHRV re recycling heat, I've seen a few try this and come a cropper with it, but could add an inline water to air heat exchanger fed from thermal store

That's what he has done, as I read it, assuming his "water battery heater" is a water to air heater battery



Inserting one of these into the supply air, fed from the thermal store, in case the MVHR heat exchanger can't take the chill off the incoming air.

 

[Worcester]

@GavinA, more than happy to pass your details on.

 

[Gavin A]

That's what he has done, as I read it, assuming his "water battery heater" is a water to air heater battery

View attachment 20841

Inserting one of these into the supply air, fed from the thermal store, in case the MVHR heat exchanger can't take the chill off the incoming air.

ah right, well then, in that case we're thinking along the same lines.


cheers Worcester

 

[dansk]

I'd expect we'd be up for that - got an additional renewables trained plumber coming on board in 2-3 weeks, so I don't have to do it all myself.

Any idea what's actually already installed?

If UFH ain't in yet, then I'd expect mr Dansk would sort that side of it out.

It also would sound perfect for a little heat pump, and / or wood burning stove with back boiler instead of the gas boiler, but obviously that depends on the scope for chimneys, space etc

I'm a little concerned about some of what's written about the MHRV re recycling heat, I've seen a few try this and come a cropper with it, but could add an inline water to air heat exchanger fed from thermal store - well, if I can remember where I nearly sourced one before for a client that fell through.

Please fire the details across and I'll get in touch.

Yes i would be more than happy to assist where i can. Thanks.