Central Heating & Controls..

bbam

Hi all,
We are currently designing the heating for our new 3200sq foot 2 story house. We've opted for a "shed" load of insulation and well controlled heating rather than pellets, geothermal or under floor...

We plan to go with;

• Conventional oil boiler ~40Kw gerkros,
• Hercules 30Kw stove,
• Triple coil stainless tank
• Solar panels for DHW,
• Standard rads,
• 2 heating zones (up & down)
• TRV's all round.

My question is regarding control units, I have looked at "www.myson.ie" & "www.heatmisershop.co.uk".
What have folks used and what sort of functionality did they get ???

Thanks all...
bbam

delly

sunnyspain, I don't feel your reply is anything to do with the problem here.

skinner2x

HI Sunnyspain,

Your system sounds similar to one I am in the process of doing.
My system is.
House is insulated to the max (2300sq ft)
Solar Hot water.
Stanley Erin stove solid fuel with backboiler.
3 coil 500l cylinder . (coil for solar, CH, and backboiler)
Warmflow 120,000 BTU condensing oil boiler. (in garage)
Its broken into 3 stat controlled zones. (or technically 4, as the hot water plumbed as a zone.
Seperate circulating pump and minivalve to feed to HW, or zone 1, or all zones if required
For the controls I am using a Schneider electric PLC (I have a backround in PLCs/electronics).
PLC can completely automate the zones to come on at relevant times, and program seperatlely for each day of the week (ie different at weekend).

I'll be connecting up this week, wish me luck (my first post)

De_man

Skinner2x firstly welcome to boards

a quick question for you, regarding your central heating...

do you have a pressurised or gravity plumbing system?


tks in advance

skinner2x

Hi De man,

System is (will be) pressurised (3 bar) , via a speed controlled pump.

towbar

We have used heatmiser to control radiators very successfully.
Generally happy with the features although it does require a bit of mind shift to not think about heating on\off times but rather required temperature at different times. Its not that expensive and I have now integrated with a pc to monitor whats going on and use the PC to set the temperatures as doing on the thermostat is slow.

We do use pellet boiler but system should work just as well with oil. Would agree with your view more insulation and oil although our pellet system thankfully hasnt had any major problems but no sure the savings are that big cosnidering investment.

I am in North East if you want to see it in more detail.

De_man

skinner2x wrote:

Hi De man,

System is (will be) pressurised (3 bar) , via a speed controlled pump.

thanks for the info, i have much the same set up

condensing oil boiler (with pipes ready for wpb later on - if it works)
4 solar panels and "solo" rads instead of the normal ones - a bit more expensive but i hope to save on the operating costs

my plumber wouldn't hook up the stove with back boiler to assist the oil heating reckons it'll only work on a "gravity" system i must get onto stanley in the morning or if you could explain to me how you connected up....

the plumber reckons i'd have a time bomb with the stove if the electricity went off, i thought a "ups" would do the job okay connected to the pump on the back boiler


if you could explain i'd very much appreciate it, i'm due to close in all the channels on the floors this week to concentrate on the works outside (finally)


thanks

towbar

I think the problem with the pressurised system and stove is that if the heat could not be dissipated fom the stove the pressure would build up significantly in the system as the water in the stove's boiler turned to steam.

Just seen it happen in another wood pellet boiler when the circulating pump sticks once temp goes over about 70. Boiler stopped fueling at 75 but within 5 minutes the temp of the water in the boiler was over 100 just with the residual flame from the remaining pellets and it blew off within another few minutes as pressure went over 3.5 bar.

Imagine same scenario in a stove where there may be no automatic way to shut down the heat quickly.

Do you need to go with pressurized system as in open system gravity flow will ensure some dissapation of heat and the expansion tank can release steam and high pressure.

skinner2x

De Man

I misled you there, I though you meant was the hot water (for showers etc) pressurised.
I'll try clarify.

Hot water (in cylinder ) is pressurised (Cylinder has 2 expansion tanks).
Plumbing is gravity feed (it also has a variable speed pump to compensate for variable no of zones switched in .)

Your plumber in right, you need to be careful. This is the reason I had to get a 3 coil cylinder, so it could circulate via gravity thru the cylinder.
Its T's off as well on the input side to the minivalves for the heaitng zones.
I have a small circ pump (stat controlled thru PLC) and minivalve into zone 1 only (hall/kitchen/living) or all zones. NOTE circ pump cannot be inline, as potentially it could stop the flow if boiler on , pump off.
Essentially by this method, I can use the backboiler to heat the water (which shouldn,t be necessary), assist the heating, or not use the heating at all (bypass valve to zone 1).
The coil in cylinder method allows you to indirectly assist the heating.

So, is your system high pressure plumbing? ie are you using the cylinder as a heat store? Well done for the forward planning for the pellet boiler. I thought about it, but as my boiler was in the garage , it would have cost too much for those zero loss pipes.
this problem wrecked my head for a while too, but i think i have it sorted now.

skinner2x

De Man

I misled you there, I though you meant was the hot water (for showers etc) pressurised.
I'll try clarify.

Hot water (in cylinder ) is pressurised (Cylinder has 2 expansion tanks).
Plumbing is gravity feed (it also has a variable speed pump to compensate for variable no of zones switched in .)

Your plumber in right, you need to be careful. This is the reason I had to get a 3 coil cylinder, so it could circulate via gravity thru the cylinder.
Its T's off as well on the input side to the minivalves for the heaitng zones.
I have a small circ pump (stat controlled thru PLC) and minivalve into zone 1 only (hall/kitchen/living) or all zones. NOTE circ pump cannot be inline, as potentially it could stop the flow if boiler on , pump off.
Essentially by this method, I can use the backboiler to heat the water (which shouldn,t be necessary), assist the heating, or not use the heating at all (bypass valve to zone 1).
The coil in cylinder method allows you to indirectly assist the heating.

So, is your system high pressure plumbing? ie are you using the cylinder as a heat store? Well done for the forward planning for the pellet boiler. I thought about it, but as my boiler was in the garage , it would have cost too much for those zero loss pipes.
this problem wrecked my head for a while too, but i think i have it sorted now.

De_man

skinner2x wrote:

De Man


Hot water (in cylinder ) is pressurised (Cylinder has 2 expansion tanks).
Plumbing is gravity feed (it also has a variable speed pump to compensate for variable no of zones switched in .)

Your plumber in right, you need to be careful. This is the reason I had to get a 3 coil cylinder, so it could circulate via gravity thru the cylinder.

you've given me an idea, must have a chat with the plumber


So, is your system high pressure plumbing? ie are you using the cylinder as a heat store? Yes, boiler using one coil, the solar panels the other


this problem wrecked my head for a while too, but i think i have it sorted now.
great stuff, at the moment i'm at the stage where everything is finishing at the same time, and it's wrecking my head, doing my best to keep on top of everything

thanks for the info, a 3 coil cylinder, might sort it out, i'll have another chat about it, this has been one of the main "problems" with the build so far


thanks lads


a pint of plain is yer only man

grassynoel

Just found this thread after posting my first boards question yesterday - some good info for what I was asking about possibilities for solar water heater + OFCH + solidfuel CH also.

From ye're posts it seems like ye went through what I am now experiencing (just about to start on site, 2900sq ft, 1.5storey). some of the stuff seems technical enough but this is what I am probably gonna do
65mm board insulation in cavity
insulated slabs on all exterior ground floor walls
Grant Condensing oil boiler in shed. Rads
6m2 solar panels on shed roof
Qualpex? dual pipe to house (c.60e/m) from shed
Set up to convert to wood chip/pellet in future - when supply and reputations improve.
Room Heating stove(s) only. I would love to set up a stanley/rayburn etc to back up the CH but have been advised against - doh!
Pressurized system (4 showers)
TRV's and 4 heat control zones.

I tried to get independent advice on setting up the heating system but found it impossible - had to ask plumbers and suppliers directly - sometimes not very independent and varying views.

So finally, the question is what kind of ballpark figure did ye guys end up paying to set up ye're systems. Thanks

skinner2x

grassynoel wrote:

Grant Condensing oil boiler in shed. Rads

Note on Grant boilers
I was pricing grant boilers, best i could get was 1900 euro for oil condensiing.
I went with a Warmflow condensing, which cost 1300 euro. Get this, the spec sheets are the same, and they both use a Relio burner, which is the heart of the device!
From the suppliers, the only diff I could get between was that the Warmflow was more difficult for the plumbers to work on (access)..
who cares???

Musha

Just finished plumbing a house with much the same spec as on this thread
Stove with back boiler
Solar for DHW
Under floor heating down stairs
Rads upstairs
Condensing Oil boiler
Triple Coil Solar Cylinder

Used System link controller and everything is working prefectly Householder is delighted.
Trick is to get your plumber and electrician talking to each other

skinner2x

Musha wrote:

Trick is to get your plumber and electrician talking to each other

Agreed. My electrician was difficult, but came round to my way of thinking (ie didn't pay him till he agreed)

ircoha

Musha wrote:

Just finished plumbing a house with much the same spec as on this thread
Stove with back boilerWhats the set up for safety in case of power failure
Solar for DHW
Under floor heating down stairs
Rads upstairs
Condensing Oil boiler
Triple Coil Solar Cylinder

Used System link controller and everything is working prefectly Householder is delighted.
Trick is to get your plumber and electrician talking to each other

Thanks