Fit bigger boiler to rayburn?

SJamieson

Member
Mixed Farmer
Morning. We have a 499K rayburn with a 23.5kw boiler.

Is it possible to fit a new, larger boiler to the existing unit? To future proof for more house radiators?
 

Stroppymonkey

Member
Trade
23.5 KW boiler (not sure if that is gross or nett) will heat a LOT of radiators! If you actually suffering from heat losses exceeding the output of the appliance then there are work arounds you can use to accommodate more heat output with better controls, night set back, hot water priority etc etc. And as serf said, better and cheaper and more efficient to have a separate stand alone condensing oil boiler than any cooker/boiler arrangement such as the Rayburn. Would advise seeking advice from a decent local heating engioneer TBH.
 

dave mountain

Member
Livestock Farmer
23.5kw is a lot of radiators but not much for hot water demand if you have more than 1 bathroom.
if you can get away with it just leave it as it is. if you need more than 23.5kw then rip it out and get a grant 46kw boiler, can still keep the rayburn for cooking, but tbh i dont miss mine any more.
 

Stroppymonkey

Member
Trade
23.5kw is a lot of radiators but not much for hot water demand if you have more than 1 bathroom.
if you can get away with it just leave it as it is. if you need more than 23.5kw then rip it out and get a grant 46kw boiler, can still keep the rayburn for cooking, but tbh i dont miss mine any more.
Sorry to disagree but……No you can’t keep that model of Rayburn working on cooker only as it needs the boiler connecting. Oversizing a boiler is bad news and will reduce efficiency and reduce its life span. Get your heat loss calcs done first. We design and install about 50 oil heating systems a year and I have NEVER needed a 46kw oil boiler on anything smaller than a large village hall or a commercial swimming pool 🤦‍♂️
 

dave mountain

Member
Livestock Farmer
Sorry to disagree but……No you can’t keep that model of Rayburn working on cooker only as it needs the boiler connecting. Oversizing a boiler is bad news and will reduce efficiency and reduce its life span. Get your heat loss calcs done first. We design and install about 50 oil heating systems a year and I have NEVER needed a 46kw oil boiler on anything smaller than a large village hall or a commercial swimming pool 🤦‍♂️
i know where you are coming from and yes calcs would be ideal, but if there is enough heating/hot water demand to justify changing from a 499k (which is actually 29.3kw boiler output, not 23.5) then surely you wouldnt p*ss about with a 35kw? i ran my 480k rayburn for years with the boiler disconnected, just capped off the fuel to LHS jet.
 

Stroppymonkey

Member
Trade
i know where you are coming from and yes calcs would be ideal, but if there is enough heating/hot water demand to justify changing from a 499k (which is actually 29.3kw boiler output, not 23.5) then surely you wouldnt p*ss about with a 35kw? i ran my 480k rayburn for years with the boiler disconnected, just capped off the fuel to LHS jet.
Oversizing appliances isn’t good, you risk short cycling, reduced overall efficiency, increased corrosion on boiler etc. If your Rayburn is undersized for your heat loss then correctly assessing the heating and hot water requirements and then modifying your heating controls, night set back, programmable room thermostats/ hot water priority wiring etc etc can all go a LONG way to sorting issues BEFORE slinging simply a bigger boiler in.
And yes, as I said you CAN modify appliances but that doesn’t mean you should nor that it’s safe to do so 😂
 

dave mountain

Member
Livestock Farmer
Oversizing appliances isn’t good, you risk short cycling, reduced overall efficiency, increased corrosion on boiler etc. If your Rayburn is undersized for your heat loss then correctly assessing the heating and hot water requirements and then modifying your heating controls, might set back, programmable room thermostats/ hot water priority wiring etc etc can all go a LONG way to sorting issued BEFORE slinging simply a bigger boiler in.
And yes, as I said you CAN modify appliances but that doesn’t mean you should nor that it’s safe to do so 😂
i am aware of all that, but if its justifiable to rip out a near 30kw boiler due to lack of capacity then surely 46kw is the natural replacement. i assumed from the OP that they are struggling for capacity but that might not be the case and a 20 or 26 kw may be fine unless its a big house. last domestic install i was involved in was 3 x 70kw alfa gas boilers in cascade so there are big houses about and 46kw isnt out of the question.
 

Stroppymonkey

Member
Trade
You work on bigger houses than me!
Obviously gas boilers modulate so over sizing much less of a problem. There is now a fully modulating oil boiler on the market which is interesting. Yes I agree that if a 30kw isn’t big enough then it needs to be bigger (or have 2 boilers linked). Hopefully OP has a decent heating engineer to fully assess situation first 👍
 

dave mountain

Member
Livestock Farmer
You work on bigger houses than me!
Obviously gas boilers modulate so over sizing much less of a problem. There is now a fully modulating oil boiler on the market which is interesting. Yes I agree that if a 30kw isn’t big enough then it needs to be bigger (or have 2 boilers linked). Hopefully OP has a decent heating engineer to fully assess situation first 👍
i dont often work on houses tbh, we just did all the heating and gas pipework as it was all black iron and the heating engineer(main contractor) was less than competent at it to say the least. bit of a difference between soldering or chucking speedfit about compared to threading 25ft lengths of 76mm steel pipe 😂
 

dave mountain

Member
Livestock Farmer
no good if you have tight spaces
you can usually get around it by carefully making sections so you can press them in, but yeah need to get the torch out sometimes. most important is make sure you do the soldering first because press fit orings dont like the heat from mapp gas 😂
 

Is Red tractor detrimental to your mental health?

  • Yes, Red tractor increase my stress and anxiety

    Votes: 309 97.2%
  • No, Red tractor gives me peace of mind that the product I produce is safe to enter the food chain

    Votes: 9 2.8%

HSENI names new farm safety champions

  • 153
  • 0
Written by William Kellett from Agriland

Farm-safety-640x360.png
The Health and Safety Executive for Northern Ireland (HSENI) alongside the Farm Safety Partnership (FSP), has named new farm safety champions and commended the outstanding work on farm safety that has been carried out in the farming community in the last 20 years.

Two of these champions are Malcom Downey, retired principal inspector for the Agri/Food team in HSENI and Harry Sinclair, current chair of the Farm Safety Partnership and former president of the Ulster Farmers’ Union (UFU).

Improving farm safety is the key aim of HSENI’s and the FSP’s work and...
Top