Changing A BBU to a combi??

[shane1]

Ive never done this, anyone give me any tips on making my life easier on the change over, ive only usually done combi to combi etc, so any help would be much appreciated, i haven't priced the job yet as i wanted to know how easy / hard it is first and what is involved step by step, if anyone has done this could you please let me know how it is done the quickest, safest way.

Thanks

 

[shane1]

There is a BAXI Bermuda 51/5 in place at the minute, and its in a bungalow, so just wanted to know how easy we are talking?

 

[adlplumbing]

these are question u need to ask

question 1 where is their cylinder do you need vertical or horizontal flue

question 2 where is gas supply coming from as you bring a new supply
from their

question 3 and how can u get rid condesate and put the blow off in

question 4 do u need to change the copper runs as some old pipe will not
stand upto being pressurized

 

[shane1]

The cylinder is literally right next to it above in a cupbard, the new boiler position will be in the kitchen with a horizintal flue and the gas will come directly in from there so shouldnt be a problem.
The blow off will be fine and there is a grid outside for the condensate to drain away, as for the pipework that is something i will have to come across, i just wanted to know what is the best bet of changing over, will i just shut off water to tank in loft, cap the cold up there then remove tank, then just take a cold feed from inside the kitchen? Look for the hot water pipe and connect that to the boiler??

As for flow and return, i take it will just be disconnect the fire and BBU and the cylinder, but which ones do i connect up together when i bring the flow and return from boiler?

 

[nogoodatfaultfinding]

Ive never done this, anyone give me any tips on making my life easier on the change over, ive only usually done combi to combi etc, so any help would be much appreciated, i haven't priced the job yet as i wanted to know how easy / hard it is first and what is involved step by step, if anyone has done this could you please let me know how it is done the quickest, safest way.

Thanks

Assuming Combi is going in different place but connecting to old pipework here goes.

1. Isolate Expansion Tank Fill and Drain heating as normal but remeber to drain BBU if accessable as well if not Pin Hole and Drain this way.
2. Isolate HW Feed Tank Fill and drain as normal although best to do this on day two if you on your own.
3. Cap and Remove usual suspects such as Vent, Cold Feed Etc.
4. Drain Cylinder and Remove
5. Connect both Flows Together.
6. Fit New Boiler
7 Hey Presto

 

[Steady]

You need to identify the heating circs from the cylinder circs. Cylinder circs will obviously be redundant when new boiler goes in.Heating circs will need capping inside boxing -in next to chimney breast-watch out for vent pipe too. Just hope nothing tees off the cylinder circs,anywhere you can't see. maybe bathroom radiator? Oh, and hope there's no dumbell valve in that boxing in which will stop the rads working when you pipe up the new boiler. Holes in side of chimney opening need filling in also if another gas fire is going in to replace previous one.
Apart from that it's a breeze!

 

[DP]

Not forgetting cleansing, controls, gas line, possible leaking joints/ valves due to excessive pressure )in relation to what you have now) to name a few.

If you are asking these questions, you have a hard task ahead of you. Can see a cheapo combi getting shoe horned here.

 

[shane1]

Ok cheers lads, im sort of getting it, i will be putting a Worcester 28i or 30si in as the customer likes his worcester's apparently, so i will be pricing one of them, ill see the flow rate difference and see if there is any en suites etc and go from there, i went out tonight to look at BBU as it isnt igniting and it is the electronic version so ill call Baxi technical tomoz and see what they suggest and get it running for him over the xmas period but he wants it gone early next year and replacing with a combi hence my post and i just said yeah no probs, not realising what was involved as i havent done one before but i cant turn work down and advice is the best form training in my opinion.
I was working in liverpool for 5 years but very rare i would come across conventional systems or BBU's so it was merely combi to combi or on the servicing & brekdown side of things where i was in my comfort zone, i have now moved back to my home territory in wales and seems like there is alot of the older systems with custmers wanting upgrades which are all new to me so it wont be the first time ill be on asking for good advice.

 

[fitz1]

remove pump.

 

[shane1]

Cheers

Im fully gas safe registered but BBU's are new to me really on the changeover front

 

[nogoodatfaultfinding]

Ok cheers lads, im sort of getting it, i will be putting a Worcester 28i or 30si in as the customer likes his worcester's apparently, so i will be pricing one of them, ill see the flow rate difference and see if there is any en suites etc and go from there, i went out tonight to look at BBU as it isnt igniting and it is the electronic version so ill call Baxi technical tomoz and see what they suggest and get it running for him over the xmas period but he wants it gone early next year and replacing with a combi hence my post and i just said yeah no probs, not realising what was involved as i havent done one before but i cant turn work down and advice is the best form training in my opinion.
I was working in liverpool for 5 years but very rare i would come across conventional systems or BBU's so it was merely combi to combi or on the servicing & brekdown side of things where i was in my comfort zone, i have now moved back to my home territory in wales and seems like there is alot of the older systems with custmers wanting upgrades which are all new to me so it wont be the first time ill be on asking for good advice.

Its on a charge ignition which are often sods for not working.
Get fire off wall and light with a lighter if it stays in jobs a good un if not change the thermocouple and manually light again.
Only problem with that is if you sort it they may not want other job doing LOL.

 

[shane1]

Right ok thanks, it does seem a right nightmare of a thing to be honest, im ok when its the standard multifunction valve but these electronic BBU's ive not come across, ill do my best to sort, i was thinking of lighting manually but its just my luck ill walk away and it will go again!

He deffo wants a new system early next year so im ok there lol

 

[Slugbabydotcom]

51/5 are notorious for this problem.
They have an ASD on them. Look at the front of the combustion chamber and look for a tube in the region of 12mm ish slighly to the right of centre.
Follow that tube down to the bottom. It blocks right there as it enters the pilot aeration port. A blast with an air duster does the trick.

 

[shane1]

Cheers slug, ill let you know how i get on with it tomorrow

 

[shane1]

Called Baxi technical when i was on site, done some resistance checks etc, turns out its the thermistor and harness from pcb, so part ordered and lets see if the are right