New combi boiler, radiators and pipes

spaghettiregretti

Is this price reasonable for a boiler, pipes and rads, for a 3 bed townhouse that jas no central heating currently. This includes the price of dosposing of the water heater. £8226 including VAT

 Remove and dispose of existing water heater

Supply and install Worcester 8000 30kw combination boiler in garage (12 year 

guarantee)

Supply and install Worcester wireless comfort controls (12 year guarantee)

Supply and install magnetic scale reducer, water shock arrestor and 

Worcester magnetic filter 

Run gas supply from gas meter to boiler

Run flow and return pipes to all new radiators 

Supply and install 8 radiators with thermostatic radiator valves

Refill and add inhibitor

£8226 including VAT

SaverRate

It seems to be reasonable, I was quoted £10,400.00 for strip out of existing heating system, install new including new gas line and Vaillant Boiler 30kw and new cold/hot water feeds throughout the property
3 bed semi 8 radiators. 

FlorayG

I was quoted £9,000 to completely replace my gas central heating system (It's so old the radiators are useless) in a big 2 bed bungalow so that sounds reasonable. 
I'm having a heat pump instead which is going to cost me only £4,000 with the available grant

spaghettiregretti

FlorayG said:

I was quoted £9,000 to completely replace my gas central heating system (It's so old the radiators are useless) in a big 2 bed bungalow so that sounds reasonable. 
I'm having a heat pump instead which is going to cost me only £4,000 with the available grant

Thank you. I told from 2 builders I know not to get heat pump as the radiators are twice as big, so in a town house would be no good. But not sure? Have you ever heard anything like this?

FlorayG

spaghettiregretti said:

FlorayG said:

I was quoted £9,000 to completely replace my gas central heating system (It's so old the radiators are useless) in a big 2 bed bungalow so that sounds reasonable. 
I'm having a heat pump instead which is going to cost me only £4,000 with the available grant

Thank you. I told from 2 builders I know not to get heat pump as the radiators are twice as big, so in a town house would be no good. But not sure? Have you ever heard anything like this?

That's rubbish. Mine will be the same size but a bit deeper - thus making them 'bigger'
Octopus will quote you and survey, the deposit is £200 so that they know you are serious but it's refunded if you decide not to go ahead

spaghettiregretti

FlorayG said:

spaghettiregretti said:

FlorayG said:

I was quoted £9,000 to completely replace my gas central heating system (It's so old the radiators are useless) in a big 2 bed bungalow so that sounds reasonable. 
I'm having a heat pump instead which is going to cost me only £4,000 with the available grant

Thank you. I told from 2 builders I know not to get heat pump as the radiators are twice as big, so in a town house would be no good. But not sure? Have you ever heard anything like this?

That's rubbish. Mine will be the same size but a bit deeper - thus making them 'bigger'
Octopus will quote you and survey, the deposit is £200 so that they know you are serious but it's refunded if you decide not to go ahead

Oh, thank you for this! I will explore that too in that case. Really appreciated! 

FreeBear

A WB 8000 combi has a decent modulation range, so is a good choice. The radiators should be sized for a flow temperature of 55°C or lower in order to be compliant with current regs. This means radiators will be larger than they might have been if using 70°C or even 80°C as the design flow temp. Going lower means the boiler is pushed further in to condensing mode which is good for efficiency. Also lowers the risk of burns if young or elderly come in to contact with a radiator. Also reduces corrosion inside the system.

Personally, I'd push for even larger radiators (using 45°C as the flow temperature) - They shouldn't be much larger than what has already been specified. With reduced flow temperatures, it is important to use bigger bore pipes to circulate heat. 22mm for feed & return, and 15mm tails to the radiators. Plastic pipe should be avoided as it has a smaller bore than copper.

Downside to putting a boiler in an unheated garage - It will need a frost protection thermostat. Consequently, during cold weather, it will be firing up at regular intervals to keep internals warm. Wasting gas in the process. On top of that, there is approximately 6% heat loss through the casing. Heat that could be put to use inside the house. Locating the boiler within the thermal envelope of the building (e.g. kitchen or hallway) eliminates the need for a frost stat and puts waste heat to better use.

Another suggestion is to put radiators on internal walls - In a well insulated property with decent double/triple glazing, there is no need to put them under windows. This could reduce the amount of plumbing needed and keep notching of joists to a minimum.

£8K is around the ballpark I would expect for a new heating system. I would usually recommend a heat pump, but if you are not replacing an existing gas/oil heating system, you wouldn't qualify for the £7500 BUS grant. Still, it doesn't hurt to size the radiators & plumbing for heat pump temperatures - Puts you in a better position for the day when there is no alternative, and a gas boiler will be a fair bit more efficient.

I put in a new gas boiler in 2023. Oversized most of the radiators by about 50%, and now regularly run with 40-50°C flow (sometimes up to 55-60°C if below freezing outside). Getting 94-96% efficiency and a very small gas bill as a result.

FlorayG said:

spaghettiregretti said:

FlorayG said:

I was quoted £9,000 to completely replace my gas central heating system (It's so old the radiators are useless) in a big 2 bed bungalow so that sounds reasonable. 
I'm having a heat pump instead which is going to cost me only £4,000 with the available grant

Thank you. I told from 2 builders I know not to get heat pump as the radiators are twice as big, so in a town house would be no good. But not sure? Have you ever heard anything like this?

That's rubbish. Mine will be the same size but a bit deeper - thus making them 'bigger'
Octopus will quote you and survey, the deposit is £200 so that they know you are serious but it's refunded if you decide not to go ahead

Radiator sizing will be governed by the flow temperature. Last century, 80°C was the default, and over time, it was reduced to 70°C. Small, very hot radiators were the norm along with the attendant risk of burns... With the advent of condensing boilers, regulations now require a design flow temperature of 55°C. So radiators will need to be larger than they used to be 20-30 years ago.

Heat pumps are designed with even lower flow temperatures in the 30-45°C range (Octopus appear to go for 50°C). Yes, you need even bigger radiators, but not that much larger than if you had used a 55°C flow temp - Perhaps 20-25% bigger. But as already mentioned, oversized radiators with a gas boiler is still a good choice.

Albermarle

spaghettiregretti said:

FlorayG said:

I was quoted £9,000 to completely replace my gas central heating system (It's so old the radiators are useless) in a big 2 bed bungalow so that sounds reasonable. 
I'm having a heat pump instead which is going to cost me only £4,000 with the available grant

Thank you. I told from 2 builders I know not to get heat pump as the radiators are twice as big, so in a town house would be no good. But not sure? Have you ever heard anything like this?

There is a lot of misinformation about heat pumps and a lot of general resistance to change.
Yes you will need bigger radiators ( as the water circulates at a lower temperature ) and you need to think ahead more/leave it on for longer. Also you need a suitable place to locate the pump outside.
Not sure where the idea of 'they are not suitable for townhouses' comes from .

spaghettiregretti

Albermarle said:

spaghettiregretti said:

FlorayG said:

I was quoted £9,000 to completely replace my gas central heating system (It's so old the radiators are useless) in a big 2 bed bungalow so that sounds reasonable. 
I'm having a heat pump instead which is going to cost me only £4,000 with the available grant

Thank you. I told from 2 builders I know not to get heat pump as the radiators are twice as big, so in a town house would be no good. But not sure? Have you ever heard anything like this?

There is a lot of misinformation about heat pumps and a lot of general resistance to change.
Yes you will need bigger radiators ( as the water circulates at a lower temperature ) and you need to think ahead more/leave it on for longer. Also you need a suitable place to locate the pump outside.
Not sure where the idea of 'they are not suitable for townhouses' comes from .

So I think because the rooms are quite small. But also the EPC is an F. I rang Worcester Bosch and they advised to get a boiler ironically bc the heat pump won't increase the EPC enough in this case (even though  EPC rating system is flawed) Glad I have tried both options though, thank you so much for your help

spaghettiregretti

FreeBear said:

A WB 8000 combi has a decent modulation range, so is a good choice. The radiators should be sized for a flow temperature of 55°C or lower in order to be compliant with current regs. This means radiators will be larger than they might have been if using 70°C or even 80°C as the design flow temp. Going lower means the boiler is pushed further in to condensing mode which is good for efficiency. Also lowers the risk of burns if young or elderly come in to contact with a radiator. Also reduces corrosion inside the system.

Personally, I'd push for even larger radiators (using 45°C as the flow temperature) - They shouldn't be much larger than what has already been specified. With reduced flow temperatures, it is important to use bigger bore pipes to circulate heat. 22mm for feed & return, and 15mm tails to the radiators. Plastic pipe should be avoided as it has a smaller bore than copper.

Downside to putting a boiler in an unheated garage - It will need a frost protection thermostat. Consequently, during cold weather, it will be firing up at regular intervals to keep internals warm. Wasting gas in the process. On top of that, there is approximately 6% heat loss through the casing. Heat that could be put to use inside the house. Locating the boiler within the thermal envelope of the building (e.g. kitchen or hallway) eliminates the need for a frost stat and puts waste heat to better use.

Another suggestion is to put radiators on internal walls - In a well insulated property with decent double/triple glazing, there is no need to put them under windows. This could reduce the amount of plumbing needed and keep notching of joists to a minimum.

£8K is around the ballpark I would expect for a new heating system. I would usually recommend a heat pump, but if you are not replacing an existing gas/oil heating system, you wouldn't qualify for the £7500 BUS grant. Still, it doesn't hurt to size the radiators & plumbing for heat pump temperatures - Puts you in a better position for the day when there is no alternative, and a gas boiler will be a fair bit more efficient.

I put in a new gas boiler in 2023. Oversized most of the radiators by about 50%, and now regularly run with 40-50°C flow (sometimes up to 55-60°C if below freezing outside). Getting 94-96% efficiency and a very small gas bill as a result.

FlorayG said:

spaghettiregretti said:

FlorayG said:

I was quoted £9,000 to completely replace my gas central heating system (It's so old the radiators are useless) in a big 2 bed bungalow so that sounds reasonable. 
I'm having a heat pump instead which is going to cost me only £4,000 with the available grant

Thank you. I told from 2 builders I know not to get heat pump as the radiators are twice as big, so in a town house would be no good. But not sure? Have you ever heard anything like this?

That's rubbish. Mine will be the same size but a bit deeper - thus making them 'bigger'
Octopus will quote you and survey, the deposit is £200 so that they know you are serious but it's refunded if you decide not to go ahead

Radiator sizing will be governed by the flow temperature. Last century, 80°C was the default, and over time, it was reduced to 70°C. Small, very hot radiators were the norm along with the attendant risk of burns... With the advent of condensing boilers, regulations now require a design flow temperature of 55°C. So radiators will need to be larger than they used to be 20-30 years ago.

Heat pumps are designed with even lower flow temperatures in the 30-45°C range (Octopus appear to go for 50°C). Yes, you need even bigger radiators, but not that much larger than if you had used a 55°C flow temp - Perhaps 20-25% bigger. But as already mentioned, oversized radiators with a gas boiler is still a good choice.

Interesting, I am definitely learning a lot from this process! I will best this in mind for next 2 quotes. 

FreeBear

Oh, one more thing - Don't forget to factor in the cost of connecting to mains gas if you don't already have it.

That might tip the balance and make a heat pump a viable proposition.