The investor offered to buy 53.5 million shares in the Sheffield-based firm at 26.25p. However, Fulcrum said Harwood's announcement was an "opportunistic manoeuvre" against a backdrop of stock market uncertainty and share price volatility as a result of the ongoing pandemic.
Fulcrum's board said it believes the tender price significantly undervalues the company and its prospects and does not reflect a fair value for independent shareholders.
It added that shareholders should take no action and neither accept the tender offer, when made, nor sell any shares to Harwood at or below the tender price.
Harwood says it believes that "the tender offer is essential in order to protect the Harwood Funds' existing significant investment in Fulcrum, as Harwood has material concerns with respect to the company's corporate governance".
It also said that Fulcrum's recent sale of its domestic customer gas connection assets, including the order book and associated meters, to E.S. Pipelines may have been an undervaluation.