Heating engineers in the house? Grant Vortex outdoor 21kw combi boiler question.

Hi all. We have a Grant outdoor 21kw combi, and, until recently we had an electric shower.  The supply to the shower nearly caught fire so we disconnected it. We’d like to connect a shower to the hot water supply from the boiler.  Question is, can the boiler handle this/will the shower experience be an enjoyable/productive one?

I’ve tried looking through the specs but can’t make sense of it. I guess it depends on the mains pressure & flow rate? What would you say we’d need as a minimum?

Any advice greatly appreciated.

will handle one shower – wont be a power shower though.

We have a 26kw of the same boiler.

this was a mistake and have since reverted to an unvented tank with the boiler only feeding the utility room sink.

Thanks trailrat. Should be o.k then, it’s only the 2 of us in a small, one bathroom 3 bed. The heating isn’t on much due to wood burners, oil prices and tight fists.

We have a Grant outdoor 21kw combi

I think you’ll struggle to run a shower.

We have a Grant 36kW combi for this very reason. It runs a very good, hot shower.

We had a 22(?) kW LPG boiler that didn’t really cope with showers. The only way to make it acceptable was to really restrict the flow, and even then, the shower wasn’t as hot as we would like, especially with colder incoming water during the winter. The problem with restricting the flow is that it becomes a balancing act between getting the shower hot and having enough flow to keep the boiler on.

The Grant combi will be better, as I’m pretty sure it has a heat store, so you’ll get a hot shower until that runs out, then it’ll run colder.

Grant combi 90 mk2 – runs a decent shower in our experience – quick google tells me mine is a 26km version so whether the additional 5 kw is potentially enough to make a difference or not, or whether all sorts of other factors such as water pressure, distance to shower etc are going to impact in addition i could only guess at.

Does the hot tap in the bath room blast at a good pressure and stay hot?

Oil combis generally have a better performance on paper for hot water production than gas ones.

Your shower “should” be better than an electric one.

Depends on mains pressure, shower unit itself.