Fine Gael TDs have warned Taoiseach Enda Kenny that the controversy over mounting customer complaints at Irish Water and its bonus culture threaten to turn it into another medical card fiasco.

During a stormy party meeting, backbenchers expressed their anger to Mr Kenny and compared Irish Water to the HSE. The dissent comes as the Government promised to give every household help paying water bills.

That follows an embarrassing Budget day blunder in which 200,000 families were omitted from two schemes to ease the pain of the new charges.

It also remains unclear if people on group water schemes will get any relief on their water bills.

Officials were last night scrambling to come up with a fairer formula for reducing the burden of water charges.

But pressure is now intensifying on Irish Water executives. Labour Party TDs also complained to Tanaiste Joan Burton about Irish Water's handling of complaints.

Irish Water bosses are to be summoned to appear before a Fine Gael internal committee and the party is holding a meeting on the problems with the semi-state company.

Deputies complained that Irish Water is not getting its message across and there is a lack of certainty about the charges.

Fine Gael TDs complained at the meeting they were getting a generic response from Irish Water when they forwarded concerns from their constituents. “It has the potential to do us a lot of damage, like the medical cards,” a party TD said.

Agriculture Minister Simon Coveney and Jobs Minister Richard Bruton had to defend the introduction of water charges.

Meanwhile, the Department of Finance admitted that wealthy pensioners will get a double handout – worth up to €150 a year – to help with their water bills, to Irish water, while many poorer families will get nothing at all. And the tax relief or package for pensioners remains unclear – if people are on group water schemes.

Well-off pensioners will be entitled to claim tax relief worth around €50 on their water bills from Irish , as well as getting a €100 social welfare top-up.

But elderly people on the basic state pension will only get €100 towards their water bills to Irish water.

And under the plans announced on Budget Day, 200,000 low-income and unemployed families will get nothing at all.

However, last night a spokesperson for Tanaiste Joan Burton told the Irish Independent: “All households will receive support in meeting the cost of water services.”

He could not outline how this would be achieved, but said that Government was examining its options.

The new water relief measures announced in the budget include a 20pc tax break on up to €500 worth of water costs – meaning taxpayers can claim up to €100 back on their bill.

However, households which don’t earn enough to be in the tax net won’t get this rebate.