Couple of issues with water pump

timetogo1

I got my boiler replaced recently. We got a combi so the plumber removed the hot water tank and replaced our pump in our hotpress.

Before the pump was just for our ensuite shower. The new pump is for everything.

We only really need the pressure for the showers. For the sinks and the toilets we have enough pressure when the pump is off. So we leave it off for most of the day as it's annoying when it turns on / off constantly if somebody flushes or washes their hands. When they were installing the pump I asked them if they could just put the pump on the showers and they said no. I was OK with that as I'm not bothered about turning it on when we need it.

A couple of weeks after we got it installed it started whining when starting up. So when I turn on first thing in the morning it makes a loud whining noise when filling up or increasing the pressure. Takes about 5 seconds. It's loud though. I presume turning it off mostly and just turning it on when we want the showers is something a pump should be able to handle. It's not consistent. I might turn the pump on 3 times in the day and only whine once, or twice.

A second issue I've noticed is when the pump is off when we turn off a tap around the house there can be a slight bang from the hotpress. I didn't notice it much at the start. And didn't care about it. Until we used the washing machine. During a cycle it can turn on / off water several times in a few minutes. So if you're in bed with a late wash you'll hear the banging for about 5 mins at the start of the wash and 5 mins at the end. I googled and found out about water hammer. I got a water hammer arrestor from Screwfix and put it at the feed to the washing machine. Made no difference.

My plumber is absent. I've asked him to come out and look at this a few times now and he's not appearing. He's avoiding me now.

Is there anything simple I can do. Neither of these issues occurred when we had the tank and the old pump. Is it likely to be the pump at fault or is it the pipework. Is it the plumbers fault or responsibility to set right? If he came out and said it was the pipes and resolved it I'd be fine paying him but he's not appearing.

If he won't come out and I get a different plumber can I claim the costs off the original plumber, assuming its a pump problem.

The new pump is a Walrus HQ400

John.G

Is the new pump feeding cold water to the combi boiler to supply HW and also supplying all the other cold water needs? Any issues with opening closing a HW tap or using the shower?. Also assume that the walrus is supplied from a cold water storage tank, (CWST).

timetogo1

https://www.boards.ie/discussion/comment/119972438#Comment_119972438

Is the new pump feeding cold water to the combi boiler to supply HW and also supplying all the other cold water needs?

Yeah I think so. If the pump is on then all taps (except for the cold tap in the kitchen sink, and dishwasher) get extra pressure. Same for the boiler. If I turn on the hot taps the boiler turns on and hot water comes out. If I turn on the pump, hot water comes out faster.

Any issues with opening closing a HW tap or using the shower?

No issues. The pump has to be on for the showers to work. The ensuite has a trickle without the pump (it's always been like that) and the main bathroom shower has a very weak flow. You could live with it but it's not great. It doesn't have to be on for any other taps. The pump is annoying for daily use, when somebody is brushing teeth, washing hands etc. the pump comes on / off every time you turn off a tap. That's why we leave it off most of the day. Plus if the toilet flushes the cistern is pumped. The main toilet is noisy when it's filled up. I can live with those though. They're first world problems.

Also assume that the walrus is supplied from a cold water storage tank, (CWST).

Yes. Tank in the attic.

John.G

Have you any info on that particular pump, cut in/cut out pressures etc, all/most of this type of pump have a little pressure vessel to stop the pump cycling on/off if no demand for water, the toilet should ideally have been fed directly from the CWST but not too easy to pipe this up sometimes. If the cutin pressure particularly is known then you could consider installing a ~ 50L expansion vessel somewhere after the pump which may give enough accumulated water volume to allow a small water draw off, including possibly the toilet flush

timetogo1

Ha. You're asking the wrong person. All I know is it's a pump. Thanks for the replies John.

I googled the manual. I found this.

What causes the HQ to stop? - The flow switch is designed to automatically stop the pump when water flow drops below 3.0-3.5L/min

If I turn on a tap (at anything more than a trickle) the pump kicks in. I think the trickle would be less than 3L/min but I haven't experimented.

I googled the expansion vessel, to me that sounds like 1: I could leave the pump on and 2: it'd stop or absorb the knocking I hear when some taps are turned off.

I'm going to ring him one more time today to see what he says (if he answers). If he doesn't I'm thinking of arranging somebody else and then I'll see what I can do to claim back any costs (if the problems are to do with the installation).