Central Heating quote - sound expensive?

[Kentish]

We have a 8 yr old house and presumably the boiler is too.

The central heating is very noisy (enough to keep you awake) and it's not air in the system (all purged OK).

It has scale and muck from when the system was installed according to a major gas supplier who have quoted us £800 to power flush it and fit a filter. We have a homecare agreement for our gas and central heating but it doesn't cover this.

Does £800 sound a reasonable price to power flush a central heating system and fit a filter?

Just want to make sure we are not paying over the odds for the work.

Thanks in advance!

K

[The jiffle king]

There have been a few topics on this recently. I think consensus was about 500 was ok, but don't get BG to do the work.

T-J-K

[jshell]

Seriously, I'd get a second opinion before splashing £800 on a 'power'-flush.

[Kentish]

The jiffle king said:

There have been a few topics on this recently. I think consensus was about 500 was ok, but don't get BG to do the work.

T-J-K

Although they are expensive (good guess BTW)

They will cover all dirt related calls with no extra charge and if the heat exchanger does pack up they replace that as well for no extra charge so whilst it seems expensive it may not be too bad.

Thoughts?

[NTEL]

£800 sounds very expensive! More info is needed though

1. How many rads are there on the system?
2. What type of boiler and system do you have? (combi boiler, system boiler, conventional boiler)
3. Have you had any leaks on the system?
4. Do you live in a hard water area? (scale only builds up in leaky systems that are being continually topped up)
5. What kind of noises are keeping you awake? (clanging, a rushing noise, a surging noise)
6. What size pipes come from the boiler and what size go into the radiators. Small bore systems can be noisy due to high velocity in the pipework.
7. If you have a conventional system, have you tried knocking the pump speed down?

[Percy Flage]

Can't you just drain it, fill it, pour the chemical stuff in the header tank, run it for a bit (couple of days) and then drain and refill again, with suitable inhibitor stuff added? It's what I did to ours (now ten year old house, done a couple of years ago for same reason as OP posts) and it seems to have worked for me. Although I admit I don't check for sludge, just how warm the rads get.

[Kentish]

anonymous said:

[redacted]

That must have been 3 years ago (you have too good a memory)

It was about hot water supply pressure though

I put a pump in eventually

You're a git for remembering that

[Kentish]

NTEL said:

£800 sounds very expensive! More info is needed though

1. How many rads are there on the system?
2. What type of boiler and system do you have? (combi boiler, system boiler, conventional boiler)
3. Have you had any leaks on the system?
4. Do you live in a hard water area? (scale only builds up in leaky systems that are being continually topped up)
5. What kind of noises are keeping you awake? (clanging, a rushing noise, a surging noise)
6. What size pipes come from the boiler and what size go into the radiators. Small bore systems can be noisy due to high velocity in the pipework.
7. If you have a conventional system, have you tried knocking the pump speed down?

1. 17 rads
2. conventional boiler
3. We've had a small leak since this problem but not a bad one, due to excess pressure
4. Yes we live in a hard water area? We have a softener in the sysrem but the BG engineer said that makes the prob worse

5. a rushing noise, a surging noise (kettling)
6. 28mm come from the boiler and 18mm go into the radiators. No microbore anywhere and it used to be nice and quiet

7. Yes tried knocking the pump speed down and whilst teh pump "hum" is quieter the kettling noise is no different

[convert]

Have you tried the Fernox products. They do quite a few, but this worked a treat on mine http://www.fernox.com/?cccpage=boiler_noise_silenc... Standard boiler running 15 rads.

[.:ian:.]

If it is really proper "kettling" ie the water boiling like in a kettle inside the boiler, you can get a noise reducing additive.

http://www.screwfix.com/prods/97540 f.e

Though it depends if its always done this, or only just started.. If its just started with no changes to the system, then it might not help, or might reappear..

[NTEL]

Kentish said:

1. 17 rads
2. conventional boiler
3. We've had a small leak since this problem but not a bad one, due to excess pressure
4. Yes we live in a hard water area? We have a softener in the sysrem but the BG engineer said that makes the prob worse

5. a rushing noise, a surging noise (kettling)
6. 28mm come from the boiler and 18mm go into the radiators. No microbore anywhere and it used to be nice and quiet

7. Yes tried knocking the pump speed down and whilst teh pump "hum" is quieter the kettling noise is no different

Hmmm...note three is interesting. What caused the excess pressure? If you have a feed and expansion tank the system pressure should be constant as it is open to atmosphere. If you have a sealed system the cold pressure should be 1 bar plus the head in metres to your highest rad or pipe. The expansion would then be taken up by the expansion vessel and the pressure should not rise to more than about 2.5 bar. The relief valve should be set to discharge at 3 Bar.

The kettling would suggest that the boiler thermostat may be set too high. Try knocking it down by say 10 degrees. Coupled with this, if you have fairly low head pressure and the pump is fitted to the return to the boiler this could cause a negative pressure in parts of the system which would also promote kettling.

Edited by NTEL on Friday 23 January 16:44

[CatherineJ]

Kentish said:

We have a 8 yr old house and presumably the boiler is too.

The central heating is very noisy (enough to keep you awake) and it's not air in the system (all purged OK).

It has scale and muck from when the system was installed according to a major gas supplier who have quoted us £800 to power flush it and fit a filter. We have a homecare agreement for our gas and central heating but it doesn't cover this.

Does £800 sound a reasonable price to power flush a central heating system and fit a filter?

Just want to make sure we are not paying over the odds for the work.

Thanks in advance!

K

Oh that old Gritish Bas Powerflush and Filter quote. You will find it cheaper elsewhere.

I kid you knot when our hot water started to slow down and go intermittently hot and cold. So I called out BG Homecare. The chap arrived and didn't even look at the boiler, he just told me it was all down to hard water. I told him we had a filter fitted, he flung open the sink cupboard door and declared he had never seen one.

However to solve my problems I needed a filter a powerflush and a new exchanger for the hot water. Then that led to him making an appointment there and then for a sales consultant to come and quote us for a new boiler where The flip did that come from I thought.

I ended up calling another local company to give me a 2nd opinion, in the end we paid £260 for a new exchanger to be fitted. I discussed a powerflush with him and he said yes, but only do it in summer and suggested it would be about £450

Edited by CatherineJ on Friday 23 January 17:01

[Roo.]

Kentish,

Where are you based?

The first person to say Kentish will get slapped legs.

[Kentish]

NTEL said:

Kentish said:

1. 17 rads
2. conventional boiler
3. We've had a small leak since this problem but not a bad one, due to excess pressure
4. Yes we live in a hard water area? We have a softener in the sysrem but the BG engineer said that makes the prob worse

5. a rushing noise, a surging noise (kettling)
6. 28mm come from the boiler and 18mm go into the radiators. No microbore anywhere and it used to be nice and quiet

7. Yes tried knocking the pump speed down and whilst teh pump "hum" is quieter the kettling noise is no different

Hmmm...note three is interesting. What caused the excess pressure? If you have a feed and expansion tank the system pressure should be constant as it is open to atmosphere. If you have a sealed system the cold pressure should be 1 bar plus the head in metres to your highest rad or pipe. The expansion would then be taken up by the expansion vessel and the pressure should not rise to more than about 2.5 bar. The relief valve should be set to discharge at 3 Bar.

The kettling would suggest that the boiler thermostat may be set too high. Try knocking it down by say 10 degrees. Coupled with this, if you have fairly low head pressure and the pump is fitted to the return to the boiler this could cause a negative pressure in parts of the system which would also promote kettling.

Edited by NTEL on Friday 23 January 16:44

We have a header tank (open system).

We did turn the boiler stat down but it makes no difference to the noise it makes, it just reaches the set temp a lot sooner.

We do have quite a low head of pressure, not sure wich side of the boiler the pump is fitted though.

I'll see if I can check on that.

Thanks for your help

[Kentish]

Roo. said:

Kentish,

Where are you based?

The first person to say Kentish will get slapped legs.

Not too far from Canterbury in Kent.

[Kentish]

Thanks all for the replies.

I'm thinking about doing a gravity flush and clean out with a cleaning solution such as the Furnox product and then a couple more flushes with clean water and then refill with inhibitor added and see whether that does the trick.

[Kentish]

NTEL said:

The kettling would suggest that the boiler thermostat may be set too high. Try knocking it down by say 10 degrees.

Edited by NTEL on Friday 23 January 16:44

Turning it down makes no difference. The boiler burner does not reduce on our boiler like ti does with some when the stat is turned down. Ours will just cut off sooner.

[Dover Nige]

Kentish,

Give Home Comfort Heating a shout (Google them). I've no association with them apart from they ripped out my old system and installed a new condensing combi system and were nothing short of excellent. Very good after sales service and the boss (Gary) was very particular about everything. They were competitive with their pricing and their attitude sold them to me. They also used my letter of praise on their website..lol!!

I'm sure they'd be happy to advise and help.

Can't see a flush being more than about £400 inclusive (tops) at a guess, though you do have lots of rads. They have the benefit of dealing with chalky water supplies due to the area they cover.

Nige.

[Roo.]

Kentish,

We used to use BG for our stuff but changed to SHS in Maidstone who have been really good. Might be worth a call.

[croyde]

BG wanted £3.5K a couple of years back to fit a new boiler. Got a local company in for £1.5K. Still too expensive in my view but BG are a bloody rip off.