Moira Niedzwiecka

Advice on DHW & heating please.

Recommended Posts

I am at the point now of having to make a decision on heating & DHW.

Chalet style 2 bed house with just 2 occupants.

147sq m, closed panel timber frame, walls & roof 0.12 floor 0.13 triple glazed.

We have 4kw PV and will have an Xpelair Natural Air 180 MVHR.

We have 6m of south facing glazing with solar coating & an overhang.

Considering 2 electric heated towel rails in the bathroom & shower room upstairs.

Possibly a couple of panel heaters & a Bio Ethanol stove downstairs.

UVC for water with an I Boost from the PV & a back up immersion in the UVC.

I have looked at Sunamp but am unsure if a good idea for me.

In my existing house I have an Efel Harmony 2 Oil Stove with a back boiler. We put it in 19 years ago when renovating & it has been fantastic but we find now they are discontinued & it is difficult to get parts or find anyone to service it as it was a bit niche. Just concerned that Sunamp may be the same.

I do not want UFH.

Any suggestions gratefully received.

 

 

 

APP01 Ground floor plan 200717 D A1.pdf

APP01 First floor plan 200717 D A1.pdf

Share this post


Link to post
Share on other sites
5 hours ago, Moira Niedzwiecka said:

 

147sq m, closed panel timber frame, walls & roof 0.12 floor 0.13 triple glazed.

 

UVC for water with an I Boost from the PV & a back up immersion in the UVC.

 

 

With good air tightness, approaching PH levels 2-2.5kW of heat input should maintain temperature to very low levels (-10°C).

 

The immersion will be the majority (not backup) heat source for six months at least for DHW. With total December PV production averaging perhaps 3.6kWh/day, DHW PV will be minimal.

Share this post


Link to post
Share on other sites
8 minutes ago, A_L said:

With total December PV production averaging perhaps 3.6kWh/day, DHW PV will be minimal.

That is enough for a bath, or 2 decent showers.  Though some days you will have to have none and catch up on others.

Share this post


Link to post
Share on other sites

We have an oil stove at the moment that is a pot burner, so a bit like a Rayburn that heats radiators & hot water and is on for about 5 months of the year. The rest of the time we heat water by the immersion & cook with electricity & pay £40 pcm  & are always in credit so immersion heater does not worry us.

Share this post


Link to post
Share on other sites

We installed a system based on this forums advice - led heavily by @Nickfromwales

 

Mains gas, 250l uvc, 90l buffer tank that feeds ufh manifold + rad manifold (for upstairs).  Plumber who's worked with me on the install had never done this before.  Fired it all up on Saturday for  the first time.  20l of gas later we have a house at 18deg (the target I set on the one stat installed so far) - with virtually no difference between upstairs or downstairs.  Next month or so should see the rads in along with their room stats.  Feels good  to get it in ready for the warmer weather? Very pleased with it all.  A big thanks to all on here who I copied from and Nick for organising the purchase of the tanks!

  • Like 3
  • Thanks 1

Share this post


Link to post
Share on other sites
2 hours ago, Moira Niedzwiecka said:

Chilblains:(

What’s the problem with chilblains and UFH, just curious!

Share this post


Link to post
Share on other sites

Wikipedia quote :

" Chilblains can be reduced by keeping the feet and hands warm in cold weather, and avoiding extreme temperature change "

Am I missing something ? :ph34r:

Share this post


Link to post
Share on other sites

When they burn & itch the last thing you want is more heat.

The only relief is a cool floor.

However, I do like the idea of being able to cool the floor in summer like Jeremy does.

What would you recommend if we did go for under floor.

Share this post


Link to post
Share on other sites
4 hours ago, Moira Niedzwiecka said:

What would you recommend if we did go for under floor.

Walking on your hands, obviously ! :D  

You haven't got a huge house, so putting ufh pipes in the slab is going to be cheaper than shoplifting. An ASHP can cool the slab in summer, and heat large convector radiators / skirting heaters in the winter if you really would like to 'jazz this up'. The options are as deep as your purse and as wide as your imagination. If you indeed have a particular medical niggle then go for what works for you, but would still suffice if the house is ever marketed. Good news is PV would drive most of your cooling and DHW ;)   

Share this post


Link to post
Share on other sites

@Nickfromwales Do you think a couple of electric panel heaters would be sufficient to heat downstairs?

Clean & no maintenance costs.

There are some quite nice discreet ones available.

We would have the bio ethanol stove for really cold days.

We are quite tight to our boundary on the side where we would have to put an ASHP & no provision has been made for ducting into the house or a power supply.

Am I on the right lines with an UVC with back up immersion & an I boost from the PV?

Share this post


Link to post
Share on other sites
On 14/03/2018 at 13:03, Moira Niedzwiecka said:

When they burn & itch the last thing you want is more heat.

The only relief is a cool floor.

However, I do like the idea of being able to cool the floor in summer like Jeremy does.

What would you recommend if we did go for under floor.

 

It's generally the contrast between cold and hot that causes chilblains. The cold makes blood vessels contract, the warm makes them open up too quickly bursting vessels (that's why they feel warm, look red and swollen).

 

Given your house's designed performance I really don't think this will be a problem for you in the future. UNLESS you do a lot of outside work or you have some condition e.g. Reynaulds. Even then can't see it happening.

 

I'd be tempted to go for plug in heaters but you have to consider re-sale... no-one will believe you that they are sufficient.

Share this post


Link to post
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