Grant 90 V3 wet on bottom of boiler housing

[gaz_ball]

Hi guys,

I recently moved in to a house with a Grant 90 V3 combi boiler installed. I happened to open the front cover this evening and found this:



That's a water/scale mix on the bottom surface of the boiler housing and then obviously quite a build up of scale on the heat exchanger and its connections. A quick feel around reveals the connections to the heat exchanger are seeping.

I just wanted to get a bit more info before calling a plumber in really. From searching around these forums I'm guessing leaks aren't uncommon in Grant boilers?! The boiler was installed when the house was built in 2007 and I'm not sure what servicing it has been subjected to but there is a sticker stating that the system has been treated with Sentinel X100 inhibitor. The date on the sticker says 2007 though so I presume this was put in when it was installed and hasn't been touched since. Should the inhibitor have been replaced/topped up before now considering we have very hard water around here?

Can anyone recommend a plumber in the Norwich/Great Yarmouth (NR13) area?

Thanks.

 

[WHPES]

Get the boiler serviced and tell them before they come that the heat exchanger needs taking off and refitting with new fibre washers. Quite a simple job and if its done on one visit won't cost as much as coming twice. The joints on heat exchangers are subject to extremes of fluctuating temperatures and quite prone to leaking over time so this is a common fault.

However judging by the limescale, I would advise the heat exchanger gets checked for performance in case the inside is getting scaled up. If you have a scale problems then a polyphosphate scale inhibitor unit in front of the cold feed to the boiler would be advisable. Also request they check the inhibitor levels in the system when they service the boiler.

Engineers can be found under the "find an engineer" section of the OFTEC website.

 

[lame plumber]

thats has said it all really

 

[Bunker]

Its also, typically, leaking from the diaphragm pin. This is not a huge problem as its mains water side rather than system pressure but will add to the limescale below.
As above, tell him to bring a tub of Fernox and a suitable container.
The limescale is more prevalent here as a little weep gets hot and dries on a constant cycle.

 

[Chalked]

Looks like someone's had a go at sometime before, looking at the state of the chrome nut on the hot outlet of the hex!

 

[WHPES]

Use decent quality hard red fibre washers not those feeble cardboardy ones that Firebird use which disintegrate in no time at all. I had some of those type in a washer kit and I threw them all away.

Not too much scale under the diaphragm pin, probably best left alone.

 

[Bunker]

I like the thick blue washers, they feel.....well, manly

 

[WHPES]

If you haven't got any, regular 1/2 and 3/4 tap connector washers work well provided they are of good quality.