Seized Mira 88 which service pack

Pickwickpick · Feb 1, 2019

I've got a customer who needs a mira 88 servicing. It had stopped regulating temperature properly for a couple of months and just recently its completely seized up, the dial will not turn.

There's two service packs available, the cheaper one (936.12), which has all the o rings, spring, spindle and couple packs of silicone grease. Then there's one that's 4x the price (904.07) which is the whole assembly.

I'm pretty certain that it just needs a strip down, good clean & the 936.12 service pack, but thought why not pick your experienced brains before I place the order.

Thanks in advance

Harvest Fields · Feb 1, 2019

Isn’t a version of this now obsolete?

townfanjon · Feb 1, 2019

Blimey thats an old shower , personally I wouldn’t put a service kit on it .
FYI mira do a fixed price repair , or did .

Best · Feb 1, 2019

I probably would buy the cheap service kit and strip the valve down and give it a clean and fit the new kit seals. I think on high pressure they are can have wear on the works, but hopefully you won’t have that.
Been a long time since I worked on the Mira88.

Pickwickpick · Feb 1, 2019

Harvest Fields said:
Isn’t a version of this now obsolete?

I don't think so, Mira have got parts for it still on their website and they're on showerdoctor too.

townfanjon said:
Blimey thats an old shower , personally I wouldn’t put a service kit on it .
FYI mira do a fixed price repair , or did .

It is old and if the shower wasn't concealed I would have recommended replacing it. My concern with replacing it is that I'll be opening up a can of worms, finding the same tiles is going to be a struggle and it was fitted by a general builder who has done some 'interesting' plumbing and other work elsewhere in the property (the state he left the electrics in was criminal). I would have to recommend ripping it all out and starting from scratch as I wouldn't want to risk being blamed for problems further down the line that were actually due to the initial installation.

I've had a chat with Showerdoctor who think its worth servicing and I've offered to the customer that if servicing it doesn't work I'll knock the labour cost for the service off the bill for a whole new shower.

Pickwickpick · Feb 2, 2019

A little update on this, service pack turned up at lunch time, went over to the customers this afternoon and stripped the shower valve. It was full of limescale and all of the rubber seals were knackered, but the pistons were still in perfect condition.

Descaled and cleaned it all, fitted the new seals, applied some silicone grease and put it back together. The dials are now working beautifully, but there's only hot water coming out. Took it apart again and then carefully opened the stopcock (conveniently its in this downstairs bathroom), no water was coming out of the cold water pipe.

Had a little chat with the customer and turns out that the knob being seized wasn't the only issue, after he had his boiler swapped for a combi last year, the shower became a lot hotter than it used to be. Had a search for an isolation valves they might have forgotten to turn back on, but couldn't find any so went up into the loft. Turns out this downstairs shower was supplied directly from the tank, the engineer that fitted the boiler had cut all of the pipes off in the loft and capped them off which cut the cold supply to this shower. Going to go back in the morning and sort the pipework out, but once that's done he will have a functioning second shower again

Harvest Fields · Feb 2, 2019

Pickwickpick said:
A little update on this, service pack turned up at lunch time, went over to the customers this afternoon and stripped the shower valve. It was full of limescale and all of the rubber seals were knackered, but the pistons were still in perfect condition.

Descaled and cleaned it all, fitted the new seals, applied some silicone grease and put it back together. The dials are now working beautifully, but there's only hot water coming out. Took it apart again and then carefully opened the stopcock (conveniently its in this downstairs bathroom), no water was coming out of the cold water pipe.

Had a little chat with the customer and turns out that the knob being seized wasn't the only issue, after he had his boiler swapped for a combi last year, the shower became a lot hotter than it used to be. Had a search for an isolation valves they might have forgotten to turn back on, but couldn't find any so went up into the loft. Turns out this downstairs shower was supplied directly from the tank, the engineer that fitted the boiler had cut all of the pipes off in the loft and capped them off which cut the cold supply to this shower. Going to go back in the morning and sort the pipework out, but once that's done he will have a functioning second shower again

On a Sunday?

Pickwickpick · Feb 2, 2019

Harvest Fields said:
On a Sunday?

Yep, don't mind working Sundays and the customer doesn't mind either. Planning on going down in London for most of next week so this is more convenient.