New install on an old system.

[Dannypipe]

I couldn't use logic's as I was quoting against other engineers who specified WB's and LLH. The bloke got 4 quotes. One company (the most successful small heating firm in my area funnilly enough) didn't reccomend a LLH and suggest one boiler not two. He told me about this, and how he immediately discounted their quote. I was pushed for time so I matched the others quotes, but with a couple of caveats. Caveats that will make me less money than the competitors quotes, but do mean the system will work better.

They all wanted to use the WB LLH which for me was a bad move. Be interesting to see how much this costs me. I'm not fussed about using two pumps. It's another £80. Won't break the bank.

 

[vern]

Jeez I am here pal, piece of pi55 have you won it? If so I have a design although I would have fitted an FS 42 CDi as they have 28 mm connections, and a plate heat ex, but I understand client wants 2 x WB's so no prob

 

[vern]

Also Danny wants the max head height from tank to top of WHERE LLH will be mounted in meters?

 

[Dannypipe]

The heat loss calc was over 40KW Vern so I couldn't have gone down that route. I don't think it's a problem stepping straight up to 28 from the boiler connections. Do it quite regularly of other installs.

Anyway, I'm always open to learning something, so please let me know your thoughts. The height from the tank to the top of the LLH is about 4.5M mate.

 

[vern]

The heat loss calc was over 40KW Vern so I couldn't have gone down that route. I don't think it's a problem stepping straight up to 28 from the boiler connections. Do it quite regularly of other installs.

Anyway, I'm always open to learning something, so please let me know your thoughts. The height from the tank to the top of the LLH is about 4.5M mate.

Right pal, 2 x 30 cdi conventional boilers, into a Broag 80 kw LLH, VERY COMPACT, 4 x 1"" female trappings for both boilers F&R'S, pipe up from LLH TO BOILER IN 28 mm, mount a Grunfos 15/60 on 28 mm pump valves, on speed 3 on the return, with a magnaclean etc before pump on return to each boiler, wire these from boiler PCB for overrun. DO NOT MOUNT ANY VALVES ON FLOW

From system side of LLH which has 2" male connections, so use 2 x 2" MI X 54 mm copper, from flow out of LLH expansion, then cold feed, then system pump with zone valves as required and ABV ETC, system pump to fire off zone valve microswitches, LLH has 2x 1/2" trappings one at bottom for DOC, one at top also, place in there a tee containing a Nabic PRV RATED at 1.5 bar assuming Round 5 m head, then above PRV an AAV, THIS WILL PROTECT THE SYSTEM SHOULD THE EXPANSION EVERY BLOCK UP belt and braces.

The boiler pumps won't pump over as they are against a good resistance of the hex they will also run cooler and last longer, the LLH ALSO BECOMES THE NEUTRAL POINT TOO!

Dont worry about WB's ON THIS LLH their pipes can go down first even on open vent, hence the built in AAV on their hex.

This will work a treat no problem done a few like this

 

[zeebeedee]

If you fit an ideal logic fit a magnetic filter, the pumps/diverters on these cant handle even a tiny bit of dirt!

 

[Dannypipe]

I'll compare the cost of the broag LLH Vern. I like the idea of the PRV. It is belt and braces though!

I won't be messing with the existing header, apart from to remove the old zone valves and fit new ones. One of the zones is run off 42mm tube the other 54, but that's only because its been an old gravity system. In my opinion the pipe sizes are totally over the top, but as I said, I won't restrict it from my header as don't want to save a few quid, and regret it.

The trouble is, the money isn't in there to do everything I want to do to the system. (Is there ever?) I'm going to have to make some compromises that I don't want to as is.

 

[vern]

I hate jobs where you have to compromise, especially for a few more quid, you can make the system sing! But that's what happens when they get too many quotes!

won and installed one recently where she had 7 quotes, simple job, no one listened to her, she had a fully pumped ideal classic, it was too small and the pump noise in her daughters bedroom was loud, 4 gave her a combi quote, the other 3 heat only with new pump.

shame she had gravity showers that a combi would have blown to bits not one of them mentioned this lol 4 out

i installed a WB system boiler job done ( other 3 out)

 

[Dannypipe]

Yeah, I would have liked my original quote accepted and could have got the system as I wanted. As it is, I've price matched another quote, and am giving more than he would for the same money, so I really can't gild the job at all.

How people find the time to get 7 quotes is beyond me. The combined wasted time for all involved would run into days!

 

[vern]

Yeah I know pal, if I had known though I may have not bothered lol, school teachers lol

Donthe job to a good standard pal and you will get more work and respect

 

[Dannypipe]

I'll keep you posted mate.

 

[Dannypipe]

and thanks by the way.

 

[Dannypipe]

 

[Dannypipe]

Did finish this a few weeks back. Just got photos off my phone. Wiring isn't the as tidy as I would like but it's only temporary as I'm going back to wire the new Honeywell intelligent TRV system in the New Year. Couldn't leave as was as I found loads and loads of live earths in the wiring centre and I had to alter it to fit my new zone valves. (Here's two of many!!)

Anyway, Customer very happy with it.

 

[Nostrum]

Nice install Dannypipe, what's in the control box then? A 10 way choccy block?

 

[IDCHAPPY]

Now can someone comment on the pumps?! LOL

I'm having a bit of a crisis of confidence as I've worked along side my dad my whole working life, but I'm doing this one off my own back. Dad can come and help me if I want it, but I want to leave the old boy in peace! I'm sure I'll be fine, but I don't want any slip ups. I sound like I'm 20 not 35!!

This will be my situation in a few years :lol:

 

[IDCHAPPY]

Nice Install Danny, I'm sure your old boy will be proud

 

[Dannypipe]

Cheers lads. Yeah there are a couple of strips of choco block in the adaptable box and a load of relays. Hence the size of it. It's got a high limit stat on the header and low limit stat with the frost stat and then relays to split the switch live. As said the electrics were a bit of a nightmare. Probably took me two or three full days. I added a temporary stat to the first floor which is the Salus box above the main box. Got to be honest, I really enjoy wiring controls even if they sometimes leave your head like mash potato.

 

[SafeGasInstall]

Welldone Danny , you got a link for that control box ?

 

[Dannypipe]

Don't know if this will work Stan. Page 398 of the toolstation catalogue. Adaptable boxes.

The neons I bought from an electrical wholesalers.

 

[Dannypipe]

(On tapa talk on the phone) off to work in a mo!

 

[Nostrum]

Out of interest, why the high and low, Danny? Do the boilers not have built in frost protection? I have never cascaded 2 boilers together as such so interested in the set up.

 

[Dannypipe]

Hi and low?? Sorry mate. Don't follow? There are two flows two returns run in 28mm to the header. The boilers do have frost stat but I fitted one in the boiler room linked back to a low limit pipe stat so the boilers will fire and prevent the pipe work from freezing and then not over run for no reason.

 

[vern]

Hi and low?? Sorry mate. Don't follow? There are two flows two returns run in 28mm to the header. The boilers do have frost stat but I fitted one in the boiler room linked back to a low limit pipe stat so the boilers will fire and prevent the pipe work from freezing and then not over run for no reason.

Nice work Danny

 

[Dannypipe]

Cheers Vern, and thanks for the advice. You see I fitted the prv in the header as suggested!