Worcester Heatslave 20/25 Water Leak & Loss Of Pressure

[m2trn206]

Hi, this is my first post on the forum , so i hope ive posted it in the correct place

I have a Heatslave 20/25 boiler and it has recently been losing pressure then yesterday i noticed a large quantity of water laying at the bottom of the unit.

I took the top off the unit and noticed the flow switch was leaking. I then turned off water, resealed the flow switch and it stopped leaking.

I mopped up all the water until dry, turned water back on and switched the boiler back on.

The the central heating wored fine/warmed up the radiators and no water leaked at the bottom.

I then got the water pressure back up to 1 bar and switched the hot water side of the system on. The pressure then started to drop quickly and water started to leak at the bottom of the unit again.

The silver insulation around the water tank is saturated with water from top to bottom but i can not see anyleak from the tank!?

Has anyone come across this before or maybe know what maybe at fault?

Thanks

 

[kimbo]

On the top left near the heat exchanger there is an automatic air vent these always leak, it is just under the control panel so you might have missed it, check that first.

 

[m2trn206]

Thanks for the reply. I had time to strip off the insulation on the thermal tank and found loads of corrosion under and around the silver unit on top ( exchanger? ). Lots of steam coming from the areas which are corroded too :-(
Heres some pics:

 

[dontknowitall]

I'm not saying you need a new boiler tomorrow, but it could be worth thinking about a replacement in the next year or two. (These were discontinued 5 years ago and boilers tend to last around 10 years.)

It's rather like a car. You can repair so many times but in there comes a time when it's not worth the repair money or time or hassle.

Coincidentally, I'm off to one of these today with the same fault (leaking flow switch). My advice will be the same to this customer.

 

[m2trn206]

Thats what we have been advised to do. The boiler is 12 years old now and there is no point chucking money at a obsolete unit when its probably better to invest in a new boiler. I know its a major expense but without it we have no hot water or heating. Getting a new Grant unit fitted this week as ive been advised they are currently the best to go for at the moment.