Hot Water to Showers not Working After Changing Taps Drainage and wastage systems and plumbing help, advice and answers

[hesm172]

Please help, novice(ish) diyer.
Saurday is changed bathroom bath and shower taps.
Could figure out how to shut off hot water (I missed the big pipe at back of airing cupboard - my wife loves to cram with towels bedding etc). But turned all the values I could find off.
So just drained the whole system (mains turned off and ran hot taps until water stopped.

Once finished turned mains and all other valves on, hot taps all work fine, but showers (we have 2 running off same shower pump) have no hot water (worked fine although pump v noisy before)?

Need some advice, pump is showermate, it has 4 pipes into it, 2 with red connectors 2 black, the red (I assume hot water) pipes one is hot and the other isn't - wondering if there is some air, and if so how I release.

Appreciate any advice - Thanks

[Colin Evans]

Sounds like you have an airlock. Assuming there is no bleed valve on the pump, first thing to try is switch off the power to the pump, then run the showers (one at a time) normally without the pump for a couple of minutes. This might clear it. If it doesn't, try connecting a hose between the hot and cold taps in the bathroom and opening both - the cold pressure should force the airlock back through the system. If you have a mixer tap, try holding a towel firmly over the outlet and opening both taps to get the same effect.
Regards
Colin Evans
PBSL Group